This is Part 7 of a series of 9 posts organized as a single work, collectively “endless”. There are 8 parts, individually published as posts on this blog, and a table of contents of the series in the 9th post. The series is organized into sections, numbered for reference, in the series table of contents and in the toc for each post. From March to June 2024 I reorganized and revised the long article extensively. This post has been most recently updated June 11, 2024.
Scope
This post mainly discusses immersion in melted paraffin (hot wax) as chain lubrication. It will begin with a discussion of paraffin. It will address:
some attempts to use paraffin in drip lubes,
paraffiin chain coating emulsions and
other chain coatings applied as fluids.
18. Paraffin
Chemistry and History
Paraffin is a wax, a dry solid. Paraffin wax is a refined petrolem product, a synthetic wax made of alkanes. Some of its properties depend on the refining. The melting point can be under 35 ºC, or over 50 or 60 ºC. A company that obtained the corporate name ParaffinCo and the domain name paraffinco.com refers to paraffin wax as “normal paraffin”, it says, on a web page about the industrial uses & applications:
Normal paraffin is a straight-chain alkane, typically derived from crude oil through the refining process. It consists of a linear arrangement of carbon atoms with hydrogen atoms attached, forming a saturated hydrocarbon chain. Normal paraffins vary in chain length, which influences their physical and chemical properties, making them suitable for different industrial applications.
The melting point of normal paraffin varies with the length of the carbon chain, providing flexibility in choosing the appropriate type for specific applications.
Due to its saturated hydrocarbon structure, normal paraffin has low chemical reactivity, making it safe and easy to handle in various industrial processes.
It exhibits excellent chemical stability, resisting oxidation and other chemical reactions. This stability ensures that normal paraffin maintains its properties over time, even under varying environmental conditions.
Normal paraffin is hydrophobic, meaning it repels water. This property is particularly useful in applications where moisture resistance is crucial, such as in coatings and sealants.
…
Normal paraffin is used as a base oil in the formulation of industrial lubricants. Its stability, low reactivity, and lubricating properties make it suitable for various applications.
In metalworking, normal paraffin-based lubricants reduce friction and wear on cutting tools, enhancing their lifespan and performance. The lubricants also help to dissipate heat generated during the machining process, preventing damage to both tools and workpieces.
…
Normal paraffin’s versatility makes it suitable for a wide range of applications across various industries. Its ability to adapt to different formulations and processes makes it a valuable ingredient in many products.
Normal paraffin is relatively cost-effective compared to other raw materials, providing an economical solution for industrial applications without compromising on quality and performance.
The use of paraffin wax as a lubricant was discussed in a paper “The Friction of Lubricated Metals” published in by the Royal Society of London in 1940. Solid paraffin wax lubricates as a solid. The reasons paraffin wax lubricates have not been fully scientifically explained. The 19th century explanation for why ice (frozen water) is slippery when other cold solids are not is still debated – see the Vox article “Why is ice so slippery“.
The practical questions about paraffin as a bike chain lubricant are:
Does it reduce friction?
Since it is a solid
how is it applied to a roller chain?
as applied to open bearings (i.e. not sealed or otherwise protected), how can a user apply it?
Cycling Uses
The manufacturer of Molten Speed Wax says lubrication with paraffin was tried in the era of Mile a Minute Murphy, (i.e. before 1900 in the early days of safety bicycles). I have not explored this factual claim.
The bicycle chain lubrication industries attempted to deliver wax in suspension or solution in fluids, but did not find ways to apply solid paraffin wax to bicycle chains comparable to the practice of bike mechanics and cyclists – lubrication with oils and fluids.
Manufacturers experimented with putting paraffin or other wax in suspension in carrier fluids in dry wax lubricants in the 1980s and 1990s. The drip “wax” lubes originated in that era were not durable lubricants, but they were well marketed and competitively priced.
Immersion
For use as a bicycle chain lubricant, paraffin can be melted down into a low viscosity (thin) liquid, and a chain is immersed in the hot wax. The liquid fills the spaces around the pins and along the edges of the rollers. When the chain is removed from the liquid paraffin cools and solidifies. The paraffin wax is a microscopically thin barrier between the metal surfaces of the pin and the “sleeve” (bushing or half bushings, roller), and the overlapping areas of the link plates. The wax adheres to the metal and apparently sheers to slip, reducing friction. Paraffin may sheer, or form surface liquid films. Solid wax is more water repellent than liquid oils – it is not as easily “washed” out by contact with the stream(s) of water droplets striking and flowing into a moving chain.
As discussed in the post Bike Chains 4 in this series, Jason Smith of Friction (“FF) tested lubricants, including paraffin in 2012 or 2013. The FF test results were published in VeloNews in an article in 2013.
The idea of using a commonly available commodity attracted cyclists ready to experiment. Readers of the 2013 VeloNews article sent questions to the magazine about immersing chains in melted paraffin to get paraffin wax into bike chains. Questions were addressed by Lennard Zinn’s Technical FAQ column in VeloNews.
The positive results of the original article and a further VeloNew article in 2014 attracted attention. A few cyclists experimented with removing chains from bicycles and applying melted paraffin. This was discussed in cycling publications – inially printed periodicals (magazines, journals). As the internet expanded, the discussion moved online. The uses of paraffin (by riders, doing diy “garage mechanic” work melting wax in “coffee cans” in the 1970s or 80s) are mentioned in a few online resources including the CyclingTips Waxing Endless FAQ article by Dave Rome (another article published online at CyclingTips that the publishers of Outside and Velo have unpublished).
Immersive waxing did not work unless the user removed factory grease from the chain by repeated immersion in mineral spirits and agitation. If a clean chain is submerged in hot paraffin, the chain will warm to the temperature of the wax; the wax penetrates into the spaces around the pins, inside the rollers and at the end of overlapping link plates. If previously waxed chain has been properly cleansed of contaminants (washed off and chain dried), it can be treated as clean.
Removing factory grease also appears to be effective for increasing efficiency and reducing wear and noise with wax emulsions/fluids, dry-drip lubes with friction reducing additives, and oily wet lubes.
Lubricating with paraffin presented challenges:
The chain had to be removed – which was not easy without master links;
The chain had to be cleaned;
Paraffin had to be melted;
The chain had to immersed, moved and cooled. The wax had to penetrate the chain and stay in place;
The wax will, as the chain makes its revolutions, break down and flake off. Small amounts of wax are expelled;
The exposed wax at edges of the chain will be contaminated;
While solid wax is more water repellent than liquid oils – it is not as easily “washed” out by contact with a stream of water droplets striking and flowing into a moving chain – waxin needs to be renewed – a chain must be cleaned and lubricated again.
Within a few years after the VeloNews article in 2013:
other proprietary immersive waxes and wax emulsions with special features (additives, special packaging) came on the market;
riders and mechanics began to publish articles and videos on immersive waxing using retail paraffin or proprietary products safely (melt the wax in a slow cooker or Instant Pot, not on a flame). Some described the process, in an ironical tone, as “Chain Spa”, etc.
Molten Speed Wax developed and marketed its proprietary paraffin product within a couple of years after the FF test results were published. Arguably, MSW did not exploit the so-called first mover advantage in the market for hard wax.
Adam Kerin of Zero Friction Cycling (“ZFC”) argues immersive waxing involves less effort and cost than using dry-drip and wet lubes, and provides benefits for cyclists/owners:
It reduces chain wear, which reduces the costs of operating and maintaining a bike; and
Paraffin wax can be applied by a cyclist for modest expense, with little effort.
The users of paraffin say several things about why waxing works, and some of the benefits:
The lubricant penetrates the chain and occupies the spaces,
A waxed chain is not oily. Dirt does not stick to a freshly waxed chain,
Paraffin resists the movement of dust, dirt and abrasive material into the chain, and
Solid wax is more water repellent than liquid oils – it is not as easily “washed” out by contact with a stream of water droplets striking and flowing into a moving chain.
The bike lubricant article at BikeGremlin notes drawbacks of wax as perceived by many engineers:
{A ] shortcoming of paraffin wax is that it isn’t mobile enough to replenish lubed surfaces after being displaced, while not being strong enough to resist being displaced after put under pedalling pressure. This is apparent after some water gets on a paraffin wax lubed chain – it quickly starts squeaking.
That is why paraffin wax lubed chains need to be re-lubed often. Also, chain needs to be completely clean and dry before lubing, so that paraffin wax can stick to it and prevent dirt from sticking to it.
Unless paraffin wax is bought, melted by heating, chain submerged in it, let to drip dry, excess rubbed off … then a “special” dry lube for chain needs to be bought, with a fluid solvent that dries off and a rather high price. Label usually says something along the lines of: “wax based chain lubricant”.
Some commercial paraffin wax based chain lubricants often have other dry lubricants added (usually PTFE), in order to improve characteristics. However, unless some oil is added as well (which beats the purpose of using a dry lubricant to prevent dirt from sticking to the chain), the problem of displacement from friction surfaces (and not flowing back) mostly remains!
A chain needs to be cleaned deeply to remove factory grease before it waxed;
Paraffin needs to be renewed or replenished after a few hundred kilometers of riding.
The wax moves as the stresses of pedalling stress the lubricant in the chain links. A waxed chain may creak if the wax is thin or weak in one place within one link. This may happen if the wax has not fully coated the chain, which happens if the chain is not clean or the wax has become contaminated.
The wax begins to break down within a couple of hundred kilometers of riding. Small amounts of wax are expelled; some of the exposed wax at edges of the chain will be contaminated. Paraffin protects a chain from dirt and water for a limited time and distance. Therefore the chain should be relubricated at short intervals. If a chain is dry and free of contaminants on the visible surfaces, it can be redipped in the same wax. The simplest method of cleaning a waxed chain used in reasonably dry and clean conditions is to put the chain on the unmelted wax and heat the wax and chain until the wax melts. The wax can be melted repeatedly. A half pound of wax will last, according to MSpeedwax, for about 8 lubrications of training chains.
Adam Kerin of Zero Friction Cycling recommends a structured approach to cleaning and lubrication:
Factory grease should be removed before a chain is installed. Removing factory grease is best done before the chain is on the bike, as it involves putting the chain in solvents. A chain that has been lubed with a fluid lubricant and used need additional preliminary cleaning. Adam Kerin and others have opinions about which bicycle or industrial cleaning products can remove dirt and contaminated chain lubricant;
The rider should clean the chain according to the contaminants encountered – dirt, water or both – after every ride;
The best practice is to renew paraffin every 300 or 400 Km. – or at shorter intervals.
A fairly small amount of wax can be melted and used repeatedly, until the wax in the pot is too contaminated.
The critics of immersive waxing view it reservations relating to:
Power Efficiency – some drip lubes may be more efficient in converting the rider’s effort to forward motion (distance, speed);
Economic efficiency – the time and cost of regular waxing;
The difficulties of relubrication during long rides or competitive events – the necessity of taking a break to install another waxed chain
Adam Kerin suggested practices that a rider can follow after recreational and training rides or commuting in wet conditions in his paper Wet Weather/Winter and waxing guide. A wet chain should be wiped down to remove any water clinging to it. A rider can use alternative chains in succession, and set aside the used chain(s) for re-waxing. Adam Kerin cautions against putting a conventional “dry” or “wet” lube on a waxed chain. It is a temporary measure which will contaminate the chain. Serious contamination can lead to a full deep cleaning with solvents. Adam Kerin suggests only using wax-compatible fluid lubricant on a waxed chain.
The manufacturers and vendors of the brand name bicycle chain waxes, and many chain wax advisers:
suggest waxing with a brand name bike chain wax, and
warn against substitutions such as candle wax, canning wax, hobby/craft wax, and industrial paraffins.
However, when ZFC tested a no name paraffin sold as candle wax, it did not do badly,
The brand name chain waxes have been used by thousands of users, and the working methods are known. Users may not know what is in a substitute paraffin or a particular batch, particularly with industrial lubricants.
Prices
The leading brand name bicycle chain immersive waxes were sold as bags of pellets. Silca Velo still sells pellets; MSpeedwax shifted to selling 250 g. (half pound) discs (cakes, pucks?) of Molten Speed Wax in 2022. 250 g. of paraffin pellets, or caked paraffin, can be melted in a small container or device – e.g. a slow cooker – in one session. The chain will not take up more than a fraction of the wax. The unused paraffin can be cooled, and melted again several times. The used chain will surrender some contaminants into the wax. The wax in the pot wax will become contaminated. The prices, per bag, as of the end of April 2022:
Mspeedwax sold Molten Speed Wax in 1 lb. (453 g,) bags for about $25 (U.S.). It changed to 500 g. bags in late 2021 and to pucks in early 2022;
Silca Velo sells Silca Secret Chain Blend in 500 g. sous vide pouches for about $53 (U.S.). Shipping charges apply, but are waived/discounted for orders over $100.
There are other manufacturers and sources of paraffin. Several immersive wax products have been developed in the post was first written. Adam Kerin of Zero Friction Cycling mentions a couple in his news update June 3, 2022, and has reviewed or discussed other.
My start in waxing in 2022
When I began to look seriously at paraffin in February 2022, Mspeedwax was not shipping wax in March and April 2022; MSpeedwax was taking orders for new formula “available 4/30”, hoping to be able to ship product by May. MSpeedwax sold and shipped pre-waxed YBN chains. I bought and received 2 chains.
Among online retail distributors of Molten Speed Wax, some – e.g. Modern Bikes – said that they had no stock in March. Others – e.g. Universal Cycles – said they had stock, but applied high shipping costs to orders and claimed that delivery problems in Canada were attributable to the US Postal Service, the Canadian Border Service agency (clearing Canada Customs), and the Canada Postal Corporation. “One pound” of Molten Speed Wax from Universal Cycle, ordered in March 2022, arrived May 4, 2022. It was a 500 g. bag of pellets. The bag had adhesive labels indicating the wax had Tungsten Disulfide. It was a bag of “new” MSW pellets.
As of mid-April 2022, Mspeedwax explained its supply chain issue, according to updates published by the Australian distributor, Zero Friction Cycling, as a problem with obtaining containers. By the end of April, I had two new prewaxed YBN chains. I scraped dirt and the residue of old lube off the chain wheels and the cassette. I did not scrub the component in solvent.
I put a few hundred Km on each new YBN chain, and notice the chains starting to creak. I did not have wax to re-wax the chains. I tried to refresh the wax with Silca Super Secret Chain Coating (Silca Velo’s wax-compatible drip lube). As the mileage accumulated, I installed a spare SRAM PC1170 chain. I cleaned it with solvents (removed factory grease), put it on the bike and lubed it with Silca Synergetic. I used that that chain to avoid risking wear of my better chains and wear of drive train components until some wax from one of the sources showed up. The use of wet lube on the SRAM PC1170 chain will have consequences. It adhered to the drive train components, and will contaminate waxes.
In late April 2022 MSpeedwax’s “4/30” had become “5/20” and the price of MSW went from $22 to $25 per 500 g. By May 4, MSpeedwax’s goal became 6/10. By May 7, 2020 MSpeedwax announced MSW was being shipped in pucks, and changed product images on its web site. Dealers – e.g. ZFC – began to anticipate filling back orders by June 2022. I received my pucks on my February 2022 order on May 20, 2022. The pucks were wrapped in bubble wrap. I received the pucks on my March order in late July. The supply stabilized, and as of 2024 there are several immersive waxes marketed to cyclists.
Emulsions
Bicycle lubricant manufacturers may process paraffin wax to create their own proprietary emulsions. A refiner, a chemical company or a wholesale distributer may supply paraffin emulsions to manufacturers of bicycle products. ParaffinCo says:
Paraffin emulsion consists of finely divided paraffin wax particles suspended in water, typically with particle sizes ranging from nanometers to micrometers.
Paraffin emulsion appears as a milky-white liquid with a smooth texture. It is easily pourable and can be diluted with water to adjust the concentration
Paraffin emulsion is stabilized with emulsifiers to prevent the wax particles from agglomerating and settling out of solution, ensuring long-term stability and shelf life.
Normal Paraffin vs Paraffin Emulsion: Specifications & Uses
Chain Coating Fluids
I have mentioned drip lubes marketed as paraffin lubrications. In 2024, some of those drip lubes have been reformulated or kept on market.
ZFC use the term chain coating to refer to several fluid products that are applied as drip lubes, including paraffin emulsions. ZFC notes that some wax-compatible chain coatings can be applied to relubricate a chain that has been lubricated by immersion in melted normal paraffin. Two wax-compatible paraffin emulsions, tested by ZFC with good results:
Ceramic Speed UFO Drip;
Silca Super Secret Chain Coating.
Some chain coating fluids are made of refined petroleum products that have not been refined to the point of being paraffin which are not as wax-compatible as paraffin emulsions ZFC has reviewed the South African fluid lubes:
ZFC has reviewed some chain coating fluids including Effetto Mariposa FlowerPower that are effective, but not wax-compatible.
I will discuss the use of drip lubes, chain coating fluids and wax-compatible chain coatings on waxed chains in section 21.
19. The Immersive Method
Removing the Chain
Immersive waxing involves working with the chain off the bike frequentlly. The master link makes removing the chain much easier, and makes working with the chain off the bike regularly feasible. Master links are discussed in Bike Chains, Part 2 in this series.
Factory Grease
The point of removing the factory grease is to install paraffin on a truly clean chain to allow the paraffin to penetrate to the interior spaces and adhere to the metal. This also makes the initial immersion and subsequent lubrications with paraffin faster and simpler. Paraffin can be removed and replaced with a liquid lubricant – but time, effort and money will have been spent. The supporters of waxing say it is seldom necessary, after factory grease has been removed and a chain has been waxed, to do another deep cleaning with detergents and solvents.
Removing factory grease from a new chain is a time-consuming and demanding project. Removing factory grease requires solvents that will penetrate the chain and carry off the dissolved grease. The solvent recommended to cut grease is mineral spirits. It is also necessary to rinse the chain with a polar solvent that will carry off any water. Industrial ethyl alcohol (ethanol) is good. Cleaning a used chain is more demanding. Removing old lube and contamination requires a chain cleaning detergent before the use of the mineral spirits and methylated spirits.
Removing factory grease, or old lube, contamination and factory grease from a chain (or from drive train components) requires buying, storing and using chemicals that have strong odours or may irritate the respiratory organs, and which may need to be disposed of according to environmental regulations. A bike shop may perform the work, but will charge by the hour. This is hard-core DIY stuff.
Dirty Wax
A reasonably clean waxed chain can be waxed repeatedly, until the wax in the pot is too contaminated. Immersing the chain in melted wax will remove dirt. MSpeedwax suggests a half pound of its paraffin can be used 8 times for “training chains” if the chain is rewaxed at intervals and the contamination is simple dust. Contaminated wax will be discarded after a few uses, and replaced with clean fresh wax. A user will observe the wax during wax jobs and learn to judge contamination.
A waxed chain requires basic maintenance. This is mentioned by Dave Rome in the CyclingTips waxing FAQ and other material. The chain should be wiped to remove water if the chain has been used in wet conditions. Dirt on the outside will come off if the chain is wiped. Some substances that adhere to a chain, such as small amounts of old wet lube degrade the wax.
If a chain has been waxed with contaminated wax it should be reset by deep cleaning and fresh lubrication with clean wax.
Hot Wax Safety
The melting point of paraffin is approximately 37°C (99 °F)., but it varies. Some paraffin waxes melt at up to 67°C and congeal at 66.4°C. The melting point of the paraffin chain lubes is above 55℃, above the range of temperatures in the temperate and tropical parts of the world. Further notes on these waxes:
MSpeedwax cautions on the wax package that MSW should not be heated above 220 ℉ (104 ℃). It recommends that the chain and solid wax be heated to 200 ℉ (93℃). The chain is placed on dry wax in the pot, and heated at the same time to the same temperature. It suggests measuring temperature with a candy thermometer. Adam Kerin of ZFC mentions in some of his articles that he thinks it is 60℃. The exact melting point is not easily measured in a slow cooker unless the user has an instant read thermometer. It is in the range of 55 to 60℃;
Josh Poertner of Silca Velo did a YouTube Marginal Gains TV channel video in September 2020 How to Hot Melt Wax your Chain. He said that Silca Secret Chain Blend melts at 140 to 150 ℉ (60 to 65.6 ℃)
At the flash point volatile vapour enters the air, increasing the risk of fire and explosion. The flash point of paraffin varies, depending on the mixture. It may be 250 to 300° C. The boiling point of paraffin is above 370 °C (698 °F). The temperatures are not precise because paraffin is a blend of manufactured hydrocarbons, often mixed with other substances. The melting point(s) and boiling point(s) of paraffin are higher than the melting and boiling points of water. An appliance that generates enough heat to boil water can melt paraffin, but will probably not boil paraffin. The manufacturers of MSW and SSCB do not put product specifications, such as melting point or flash point of the wax on the Internet.
The bicycle chain waxes have additives. The additives do not seem to produce gases that can harm the user, and have minor environmental effects. Without disclosing amounts, the manufacturers list the lubricating additives:
Modern bicycle chain wax advisers discourage the methods said to have been used by the populist mechanic/riders in the 20th century: melting paraffin on a stove top, camp stove, or outdoor burner (e.g. a camp cooker that home brewers might use to brew beer or camp chefs would use to deep fry a turkey in oil). Even if you are careful, shit can happen in many ways – slip on the floor, step on lego, bitten by bug, distraction, inattention, pets, kids, zombie apocalypse. The wax can spill and catch fire from an open flame.
Waxing Nordic (cross country) skis was/is required with wooden skis. and wooden skis with laminated plastic bases. The Norwegian firm Swix made – and still makes a range of ski wax cylinders to rub on to skis to promote glide on the tips and tails and grip under the “kicker” section. (Swix has not brought abicycle chain wax product to market). Some ski waxes were melted by heating a waxing iron with a torch, melting the wax on the hot iron and dripping liquid wax on the ski bases, and smoothing/distributing it with the hot iron. When I was younger and confident, risk meant nothing … Waxing skis has changed too.
Slow Cookers
MSpeedwax and ZFC advise using an electric cooking device called a slow cooker (Crockpot™ is one slow cooker brand). Slow cookers are a mature electric appliance technology. Electric multi-cooker appliances such as the Instant Pot™ are electric pressure cooker devices with “smart” controls and slow cooker functions. Basic slow cookers with ceramic inserts (crocks), without timers or “smart” controls have 3 or 4 settings: Off, Low, High (or Off, Warm, Low, High). The heating element is in a belt in the metal case that surrounds the insert. The element is always on; the switch controls the watts of power that to the heating element. This kind of slow cooker may heat to about 100 ℃ (212 ℉) in spots at the outer edges. It takes over 30 minutes on high to warm a chain and a 225 g. (1/2 pound) of wax to about 65-70 ℃. The contents will get hotter as time passes, specially with lower amounts of contents. A small or medium slow cooker will hold a chain – even two or more chains, and melt enough wax to immerse the chain(s).
MSpeedwax advises to use a slow cooker on high, and set a timer. ZFC advises using the low setting. Low will melt the wax. It takes longer, but is safer and gives the user more time for other things. MSpeedwax suggests a slow cooker with a small crock (1.5 or 2 quarts), and discourages using 4 or 6 quart models. Adam Kerin of ZFC uses large oval slow cookers in videos – he has them in his shop and uses them to wax multiple chains in one session. Adam Kerin provides advice on the ZFC site on locating places that sell 1.5 and 2 quart slow cookers in New South Wales. He recommends staying with small or medium (3.5 quart) slow cooker devices. Basic slow cookers were and still are available in small (1.5 or 2 quart), medium (1.5 or 4 quart), and large ( 6, 6.5 or 7 quarts). Larger retailers still carry brand name small slow cookers with ceramic inserts. In March 2022, I located a 2 quart slow cooker at a Walmartstore in Victoria BC for under $30. Small used slow cookers are available. Buying a small slow cooker is an inexpensive way of getting a dedicated device. It isn’t an elegant device. It uses electricity. It is less efficient than other appliances, but it draws little current.
MSpeedwax advises that the chain should be in the slow cooker, and should heated with the wax. ZFC agrees. Adam Kerin adds that If the chain was left out, the chain should say in the hot wax at least 5-10 minutes.
Some advisers, e.g. the narrator in the Bikes and Blades channel video, suggest a device designed to melt waxes used in beauty spas. Small Rice cookers may be about the same size as small slow cooker. The automated heat controls of rice cookers are set up to bring water to boil quickly and then simmer. MSW has not discussed rice cookers. ZFC says rice cookers are not a good idea for heating bicycle chain wax.
MSpeedwax and ZFC use a swisher tool to manage handling the chain while the chain and wax are hot. A tool that sticks up out of the wax is necessary – it is not feasible to get the chain out of 70 to 100 ℃ liquid without a tool. MSpeedwax sells one ($15 US) but has posted an article “Making a Swisher Tool” with detailed dimensions to make one by cutting and bending a metal coat hanger. The dimensions are for a tool that will lay a chain in the bottom of a small or medium slow cooker. When the waxed chain is removed, the chain can be removed from the swisher (use gloves – hot) and hung over the pot (if the working space is ready) to catch hot melted wax that will drip from the chain until the chain cools and the wax congeals in place. The pot, if you do not plan to cook in it, can store the wax, which can be reused.
Instant Pots™, Multicookers and other devices
Silca Velo suggests using an Instant Pot™ (or a comparable multicooker). An Instant Pot can melt paraffin, safely, using the slow cooker program setting. Silca Velo executive Josh Poertner recommends, in the Silca Velo waxing video, using the multicooker slow cooker settings. . As Mr. Poertner demonstates, an Instant Pot is faster to reach the desired temperatures than a conventional slow cooker. Silca does not appear to be concerned about chemical effects of overheating the wax. Silca does not think the risk of heating above the flash point is serious. An Instant Pot™ should hit a burn warning and shut down before it heats the contents to the flash point of paraffin in any of its programs. The high energy programs that need the lid locked should not be used to melt bicycle chain wax.
Other videos on other sites (e.g. Russ Roca at Path Less Paddled) show users using the sauté program. The wax melts from the bottom. The user can break the cooler crust and stir the wax to distribute the heat. The user may have to tend the pot.
Instant Pots are electric pressure cookers, with powerful heating elements to heat fluids to temperatures above 100 ℃, and safety features to prevent burning or overcookingfood. An Instant Pot’s sensors and programs turn the power off and on to maintain the temperature. Josh Poertner said in the Marginal Gains video How to Hot Melt Wax Your Chain that an Instant Pot was better than a conventional slow cooker at melting paraffin. Mr. Poertner suggested putting the wax in the Instant Pot’s liner/insert/pot and melting it in the pot. He recommends buying a liner/insert/pot for wax, and keeping the wax liner in the garage or workshop. He would use a multicooker without the pressure lid, in a lower heat program.
Multicooker devices can be operated without the pressure lid in slow cooker and sauté programs. The medium slow cooker program setting puts out comparable heat to a conventional slow cooker on low; the high slow cooker program setting puts out comparable heat to a conventional slow cooker on high. Culinary publications – e.g. America’s Test Kitchen – warn that Instant Pots™ heat large amounts of water (4 quarts in a 6 or 8 quart pot) so slowly in the slow cooker program settings that the water will not reach temperature that the user expects. The low or medium sauté settings can melt wax or heat water faster than the device in slow cooker mode, but may cut out when the device hits the top of a range. The heating element of an Instant Pot heats the food at the bottom of the pot (nearest the heating element) to these temperatures, which are lower than the flash point of paraffin:
Setting
℃
℉
Slow cooker medium
88-93
190-200
Slow cooker high
93-99
200-210
Sauté low
135-150
275-302
Sauté medium
160-176
320-349
Silca Velo suggests a way to use an Instant Pot with Silca’s Secret Chain Blend Wax – putting the resealable waterproof plastic bag into hot water in the Instant Pot liner/insert/pot. Silca describes the bag as a sous vide bag; the point is that the bag can be placed in near boiling water and will not melt or degrade. The Instant Pot is used to heat water quickly to a temperature that will melt the wax, a temperature at or below the boiling point of water (212℉; 100℃). The pouch is put in the water; the wax is melted without melting or tearing the bag. In this method, the chain is waxed in the bag and the wax does not touch the pot.
In the Silca Velo video, Mr. Poertner builds a swisher with a used spoke, and uses it to lower the chain into hot wax rather than putting the chain in with the unmelted wax. He says that the liner/insert/pot can be removed to a place where the chain can be hung.
Silca endorsed using an Instant Pot™. This approach works if you have a device and use it safely. Buying a liner/insert/pot for wax may be more expensive than buying a dedicated slow cooker. You may be reluctant to operate an Instant Pot outside your kitchen, or reluctant to carry a pot of hot wax and a chain around.
Some users have tried to adapt tdevices used to melt wax for beauty industry uses (i.e. depillatory), but devices for that industry may not melt wax to the proper temperature.
Some specialized cycling industry products were in the markets in late 2023 or early 2024. Cyclowax sells a wax pot in Europe. Silca has a special hot that will handle paraffin and a special wax developed by Silca to strip factory grease and wax a chain in one step.
Temperature and Agitation
MSpeedwax recommends using a candy thermometer to check the temperature of the melting/melted wax. It said when the wax was heated to 200 ℉ (93℃), the user should agitate the chain for 45 second and take it out. In ZFC videos, Adam Kerin uses a digital thermometer and says the user should agitate the chain. ZFC does not have a recommendation on how long to leave the chain in the wax if the chain has been heated in the slow cooker.
Mr. Poertner of Silca Velo demonstrated the use of a non-contact infrared thermometer to check the heat of the wax, at the surface, as it heats and cools in an InstantPot. Russ Roca of the Path Less Pedalled site uses such a device in his November 2021 video “Watch This before you Wax your Bicycle Chain“, basically following the Silca method. Silca is looking for melted wax – above 140 to 150 ℉ (60 to 65.6 ℃). Silca agrees that a chain should be agitated when the wax is melted. Mr. Poertner recommended leaving it in the wax until the wax begins to congeal. If a user knows the congealing temperature, a user with any device that reads the temperature can leave the chain in the pot and take it out as the wax is congealing. This means, I think, less wax will drip off or out of a chain?
Chain Spa
The user needs to have or acquire devices, and set up a working space and routine to use wax.
20. Wax-Compatible Fluids
The solid wax on a waxed chain should block dripped fluid lube from penetrating the chain when the wax is fresh. After the chain has been used for a while, a dripped fluid may have some spaces that it can penetrate. The main direct consquences of using a fluid on a waxed chain:
The fluid may lubricate places where the wax has been compressed, displaced or deteriorated;
A fluid may trap contaminants or weaken the wax; and
The user may need to reset the chain to get rid of contaminants including the residue of the fluid by deep cleaning before re-waxing.
ZFC’s advice was to not use most drip lubes on a waxed chain, including the traditional low reputation dry-drip lubes marketed as depositing a wax or waxy lubricant on the working parts of a chain. ZFC says that wax-compatible drip lubes can be used on an immersion waxed chain. The term seems to refer to a lubricant that will come out of a chain immersed in melted paraffin without contaminating the paraffin or interfering with the application of melted paraffin to the chain. Adam Kerin said, at one point:
Can I use a drip lube to supplement waxing? Sort of. I have tested Smoove with msw, and if a single application (as per my advanced [Smoove] application guide in instructions tab), and you run that application until it is starting to feel a bit dry, then re waxing straight over seems to go ok – just not you will be contaminating wax in pot somewhat. Same with UFO Drip. I have heard from a customer similar with Squirt (which is same type of lubricant as Smoove). If you add any other drip lube on top, then you will need to fully strip clean and prep chain again prior to waxing following Waxing Zen Master guide – with the addition of boiling water rinses first to melt off majority of wax before moving to solvents. Remember for chains the wax needs to bond to clean film free chain metal, if you put drip lube on top and then just rewax – expect wax will not bond to chain metal, and it may contaminate wax in the pot such that all future waxing’s wont go too well either. Smoove / squirt is often used for long extreme events like 24hr mtb racing or mtb stage races over top of msw as that works brilliantly, but cleaning prior to re waxing after is required to keep wax in pot clean and ensure good wax bonding to chain metal.
Silca Velo promotes Silca Super Secret Chain Coating drip fluid as almost chemically identical to Silca Secret Chain Blend immersive wax, and requires users to “ultra clean” a new chain, to remove factory grease. Silca Velo sells it as the cold equivalent of hot wax in a drip bottle. It is low viscosity (very runny) drip. It must be left to dry. If factory grease is not removed, or if it is not dried, it will not lubricate as well as advertised – or as reported by ZFC. Applying this stuff makes a mess; a lot of fluid is wasted dripping off the chain. Super Secret Chain Coating was intially sold in 4 ounce and 8 ounce dripper bottles. Silca later released the product in 12 oz. quantity in a 16 oz plastic jar, for immersing a chain in the product. There is no video for the use of this jar. ZFC has not done a report on this method of application. A user posted a video April 1, 2022 of using a chain cleaner cassette tool to apply the product.
Josh Poertner of Silca Velo addressed topping up an immersively waxed chain in the March 2021 Marginal Gains TV video “Choosing the Best Chain Lube“. When a hot immersion is not possible. and Silca Super Secret chain coating drip is not practical (the user has to give the fluid coating 24 hours to penetrate and dry), his solution, within the Silca products, is to use the oil based Silca Synergetic wet lube for the event or ride. For a rider who rides waxed chains, this means changing chains before the event or, resetting (deep cleaning and hot waxing) the chain before (and after) the event/ride.
Silca recommends “topping up” a chain waxed with Secret Chain Blend by dripping Super Secret Chain Coating on the waxed chain, as demonstated in the Silca Velo YouTube channel “Ask the Expert” video episode 7 “Chain Maintenance“. Josh Poertner presented this advice again May 11, 2022 in the Silca Velo YouTube “how to” episode How to Extend the Life of your Hot Wax Treatment. In the “how to” video Josh Poertner:
gives a reason for using a wax-compatible fluid lube. He says that the original wax is compressed and displaced, leaving spaces that a fluid will penetrate, providing addtional lubricant;
suggests that the chain should be cleaned by running it through a microfiber cleaning cloth before dripping a wax compatible fluid on the chain.
I used Silca Super Secret Chain Coating to top up MSW waxed chains in April 2022. It worked when I gave the chain coating fluid time to set.
Adam Kerin does not address the time requirements for low viscosity liquids to dry or set. Using a fluid that needs time to set is not feasible when the lube is applied during a ride when a rider on a long or extreme ride on a waxed chain needs to relube during the event.
Adam Kerin of ZFC addressed the use of wax compatible chain coatings in the ZFC YouTube video Episode 18 Key Learnings from Lubricant Testing May 8, 2022. He suggests (at about 6:30 in the video), for a rider who uses a wet lubricant for a long ride, using the “least wet” product. His advice for best option for a multi-day event or a bike packing trip (at about 40:15 in the video) depends on conditions. He suggests wax compatible drip lubes can be used to top up a waxed chain if on a ride under dry condition, when a rider is making a long stop – such as stopping overnight on a long ride. He favours owning and using a second waxed chain and carrying and changing to the replacement chain on a long ride under wet and very dirty conditions, or using a “dedicated race chain”. Eventually his advice involves compromises; there is no free lunch with chain lubrication.
In the CyclingTips NerdAlert podcast March 16, 2022 “Finding the best chain lube for your needs” Adam Kerin expanded on using fluid chain coatings with a waxed chain. He mentioned Ceramic Speed UFO Drip, Silca Super Secret. He mentioned, in passing, Rex Black Diamond which is a wet lube. (The Finnish ski wax firm Rex released two bicycle chain fluid, 2015-2022.) ZFC has tested and reported on UFO Drip, Silca Super Secret. There is no ZFC report on the Rex product. ZFC has not reported structured test reports of any of these products to “top up” an immersion wax. The site has notes that Rex Black Diamond was in the store and being tested. In the “Concise” waxing video, posted in April 2022, at the 10:55 point, Adam Kerin recommends 3 wax-compatible drip fluid lubricants for use to refresh the lubrication on a waxed chain:
Silca Super Secret Chain Coating;
Ceramic Speed UFO;
TruTension Tungsten All Weather.
Adam Kerin recommends using these products, as needed, to keep the chain running smoothly, between immersive applications of melted paraffin. He suggests a few wax compatible products can be used 3 to 5 times between immersions; he still recommends immersions as the primary way of re-lubrication of a waxed chain. He followed up with a video in September 2022 – ZFC YouTube Channel Episode 21, Lubricant Choice Guide.
This post was written in the spring and summer of 2022. I stopped working on it, subject to corrections, August 19, 2022.
Covid-19
The Pandemic
The SARS-CoV-2 (Covid-19) pandemic is a mass infectious disease, caused by repeated mass infections with SARS-CoV-2 viruses. The name means:
The virus causes sudden acute respiratory syndrome (SARS), a serious illness systematically described during and after the SARS outbreak of 2002-2003. SARS affects the organs of the respiratory system, like an influenza.
The original virus was different from the virus(es) that caused the SARS epidemic in 2002-2003, SARS-CoV-1.
The original SARS-CoV-2 virus was:
contagious – it infects people easily and infects more people; and
virulent – many infected people experience severe symptoms.
An outbreak of an infectious disease is a crisis if the illness cannot be treated and or resolved naturally without consequences. Epidemics are outbreaks of infectious diseases that occur when the number of infected persons increases rapidly. Pandemics are large epidemics. The illness or virus SARS-CoV-2 became an epidemic in December 2019, and a pandemic in March 2020. Features of this infectious disease were apparent by January 2020:
Pre-symptomatic (infected, but not sick enough to show symptoms of illness) persons could transmit the virus;
The virus was airborne – an infected person could transmit the virus by exhaling and an uninfected person could be infected by inhaling.
In many infectious diseases animals infect humans by transmitting a pathogen – e.g. mosquitoes carry a parasite that causes malaria – but humans with the disease do not transmit the pathogen. The SARS-CoV-2 disease began as a spillover, or zoonotic outbreak in Wuhan, a city on Yangtze river in Hubei province in central China in late 2019. Previously a related SARS-CoV virus had infected bats that denned in caves in Yunnan province in southwestern China, several hundred Km. from Wuhan. The bat virus had spilled over and infected miners working in bat-infested caves in 2012. Chinese scientists had collected sample of bat viruses since the outbreak of SARS in 2002, and had collected samples from the Yunnan caves. The lab leak theory explains how the virus reached Wuhan and spilled over. It was not supported by scientists at first, and discouraged to avoid antagonizing the Chinese government, or to minimize knowledge of the scope and risks of scientific research into viruses.
A widespread endemic disease with a stable number of infected individuals is not an epidemic. Since the beginning of the Covid-19 epidemic, scientists and pundits speculated – with wide publicity – that SARS-CoV-2 would become an endemic illness. Endemic refers to repeated infections by a pathogen that has not been eradicated – a pathogen that will infect humans for a long time or forever. Endemic diseases can be serious. People heard about endemic often and many people began to think it meant mild illness.
Pandemic fatigue is not a biological effect of a pathogen. It is a sociological term fordecision making by thousands or millions of persons. It is a concept like herd mentality.
Infectious Diseases in History
Notable infectious diseases:
The Spanish flu 1918-1920 (it orginated in Kansas, USA and went to Europe with Americans in WWI) was the largest pandemic of the 20th century. It was a zoonotic viral disease. The virus was an influenza A virus in the H1N1 lineage – crossover of a swine flu. The pandemic was controlled with public health measures, and ended when the virus stopped being transmitted to new victims. A vaccine was not developed or used.
The viral disease smallpox caused several epidemics and pandemics. It was one of the first infectious diseases which was controlled by vaccination. It may have been extirpated.
Tuberculosis is a bacterial disease. It has become rare in Europe and North America and can be treated but remains a serious public health problem in most of the world.
Polio is a viral infectious disease. There were epidemics in the United States and Canada as recently as 1950. It has been controlled with a vaccine and was believed to have been extirpated in the Americas. In 2022 outbreaks were noted in Afghanistsan, Pakistan, parts of Africa, Israel, and the U.K. A case was recorded in the U.S.A.
Smallpox and other illnesses affecting Indigenous residents of the Americas were introduced by contacts with Europeans in the 16th,17th and 18th centuries. America’s distance from Europe, Africa and Asia protected the living residents of the lands now occupied by the USA and Canada from many later epidemics and pandemics. Americans in America were infected during a few major outbreaks of the infectious diseases above in the 19th, 20th and early 21st centuries. People in the other parts of the world were affected by pandemics and serious epidemics in the 150 years before 2020 including:
“Russian Flu“, the viral pandemic in Russia and central Asia 1889-1890;
“Asian Flu“, the pandemic outbreak of the A/H2N2 virus in southern China in South Asia 1957-1958;
The 7th pandemic of the bacterial illness, Cholera, in Southeast Asia 1961-1975;
“Hong Kong Flu”, a pandemic outbreak of the H3N2 virus in Hong Kong, China and South Asia 1968-69;
1977 Russian Flu, an outbrief of an H1N1 lineage virus, Influenza A/USSR/90/77
Some people survived diseases, and did not become reinfected. Eventually medical science explained the model of the immune system. Medical practitioners after trial and error experiments started vaccination against smallpox by the end of the 18th century.
Breakthrough infections occur when vaccinated individuals (or individuals believed to have recovered from an infection) becomes infected with the illness, because the indidual’s immune system, which has been strengthened by a vaccine or experience with an earlier infection has failed to provide complete immunity against the pathogen.
Covid-19 in 2019-2021
There had been no vaccines for the Covid-19 virus in 2020. The American government subsidized vaccine development and expedited regularatory processes. The Warp speed program affected the development of vaccines effective against the virus by the ended of 2020. The Pfizer and Moderna vaccines protected people from infection with the original virus, and provided protection from the severity of the illness caused by infection with some of the variants . The campaigns in the first part of 2021 to vaccinate adults in the USA and Canada, including BC, with two doses of those vaccines were regarded as successful. The leaders of drug companies said, in 2021, that they could produce new vaccines to immunize people against variants of Covid-19. The public health officials were hopeful.
When vaccines do not provide immunity, and an illness cannot be treated with a medication, healthy people should avoid contact with persons who can transmit the pathogen. Government health officials/authorities used non-pharmaceutical interventions (“NPI”) in 2019 and 2020, mainly aimed at reducing social contacts:
Lockdowns and some other NPIs shut down travel, hospitality and retail industries in North America and Europe. Lockdowns in Asia, including the Republic of China affected resource extraction, manufacturing, transportation and commerce.
The American federal government and some other governments subsidized the development of vaccines, as noted.
Other governments committed to buy the vaccines. The vaccines were developed, approved, manufactured, distributed and used by early 2021;
Scrubbing surfaces and handwashing may have helped, but may have been theatrical;
Masks initially said by public health officials in North America to not be to protect individuals from inhaling the virus and to not prevent individuals from transmitting the virus. Masks were policy in the Republic of China.
The initial North American public health advice may have been stated to prevent runs on masks in the early months before masks became more easily available but the public health advice and policy shifted:
In February and March [2020], Fauci, the World Health Organization, and the CDC all recommended against protective masks for non-symptomatic members of the public. Their line was: don’t bother. On February 19, Fauci told USA Today, “In the United States, there is absolutely no reason whatsoever to wear a mask.” On March 8, as scientists estimated tens of thousands of undetected Covid cases in the US, Fauci told 60 Minutes, “There’s no reason to be walking around with a mask. When you’re in the middle of an outbreak, wearing a mask might make people feel a little bit better and it might even block a droplet, but it’s not providing the perfect protection that people think that it is.” In the same interview, laying the foundation for a fog of disinformation that is still very much with us, Fauci suggested wearing a mask might actually increase the risk of contracting the virus, “Often, there are unintended consequences — people keep fiddling with the mask and they keep touching their face.”
Two weeks later, at an April 3 press briefing, the White House reversed its guidance. Now authorities were advising us to wear “non-medical cloth” face-coverings in public spaces. (Fauci didn’t attend that briefing, prompting a round of “where is Fauci?” speculation from his fans on Twitter, but also sparing him the embarrassing display.) Surgeon General Adams, who had tweeted on February 29, “Seriously people- STOP BUYING MASKS! They are NOT effective in preventing general public from catching #Coronavirus,” acknowledged that the shifting guidance had been “confusing to the American people.” … And Trump, adopting a vague and unhelpful line on masks, one he’d maintain basically until contracting the virus himself, said, “It’s going to be, really, a voluntary thing. You can do it. You don’t have to do it. I’m choosing not to do it, but some people may want to do it, and that’s okay. It may be good.”
The flip-flop was a blow to the integrity of public health experts. It fueled and credited the suspicions of conspiracists — right-wing media outlets continue to insist that masks don’t help, cause health problems, and that mandating them is an oppressive imposition of the liberal nanny state. And it provided an opening for Trump to sow further doubt and confusion.
Masking policy did not require highly effective masks, and was not enforced rigorously. Masking was an effective NPI in Europe, North America and other areas where vaccinations had been widely administered. NPIs became “mandates” in 2021:
requiring proof of vaccination to work, enter public spaces or obtain services, and
masking for access to places where people gather.
The mask mandate became a principal enforced NPI in the Canadian province, British Columbia (“BC”) by mid-2021 when over 70% of the adult population had received two doses of the approved vaccine. Combined with other measures, including investment in vaccines, moderate NPI measures worked. In the absence of provincial government rules, businesses could recommend that customers and visitors wear masks in indoor public places, but could not require it. The BC indoor mask rule was removed briefly in the summer of 2021, on the assumption that the vaccine program had immunized enough people to make the public safe. Masks became uncommon and public spaces including restaurants, food courts, stores and malls got busy. As the restrictions were lifted, infections went up. The BC mask mandate was restored by the end of August 2021, and several other NPIs were left in place until March 2022.
Several variants of Covid-19 caused by mutations were discovered; several virulent and contagious variants were identified by the World Heath Organization as variants of concern. Several variants that evolved and circulated, including Alpha, Beta, Gamma and Delta.
The Canadian federal government and provincial governments collected data about infections and severity of illness. The data was published on the Web in daily data dashboards through to the end of 2021
News and personal action
The Covid-19 virus and the pandemic were in the news constantly in 2020. The colume (i.e. amount) of news was overwhelming and unmanageable, and the news was contradictory and changeable.
The 2021 work in the Best American Science and Nature Writing series contains works published in 2020 . In part, it demonstrates the depth of discussion of the Covid pandemic in some publications in 2020. The Covid section begins with Zeynep Tufecki’s article in The Atlantic in September 2020 on the Overlooked variable, about the stochastic variability of the dispersion rate of the virus, a factor that was and has not been widely discussed in the media. Other articles about the pandemic address lack of personal protective equipment, the management of care homes for the elderly, vaccines, epidemiology, and the outbreaks of false news about medical treatments and public health.
Omicron
Variant
Covid-19 variant B.1.1.529, also known as BA1, (the first Omicron), was reported in South Africa in November 2021. It spread rapidly. It appeared to become prevalent, and has mutated into new lineages. BA1 Omicron was more contagious than other variants, but less severe. The vaccines, although they did not provide immunity, mitigated the severity of respiratory symptoms in healthy young and middle aged adults.
BA1 was in Canada by November 2021. The need for boosters was clear by November. In January 2022, Canadian public health officials confirmed that Canada, like the USA, was experiencing a fifth wave of Covid-19 infection and illness. Canadian governments began to run to administer “booster” doses of vaccine in late December 2021 and January 2022. In BC 1st vaccine boosters (3rd shots) were administered in December 2020 and January 2021. The government did not get the clinics set up in time to administer the shots until the end of the year.
The journalist David Leonhardt argued, in the New York Times Morning Newsletter, that the Omicron variant, as he understood it, was causing milder illness. He suggested that the great majority of people in America could live with Omicron:
Somebody infected with Omicron is less likely to need hospital treatment than somebody infected with an earlier version of Covid. …. Hospitalizations are nonetheless rising in the U.S., because Omicron is so contagious … …. Omicron is not just less likely to send somebody to the hospital. Even among people who need hospital care, symptoms are milder on average than among people who were hospitalized in previous waves. A crucial reason appears to be that Omicron does not attack the lungs as earlier versions of Covid did. Omicron instead tends to be focused in the nose and throat, causing fewer patients to have breathing problems or need a ventilator.
….
Dr. Leana Wen, Baltimore’s former health commissioner, wrote a … Washington Post article in which she urged a middle path between reinstituting lockdowns and allowing Omicron to spread unchecked. “It’s unreasonable to ask vaccinated people to refrain from pre-pandemic activities,” Wen said. “After all, the individual risk to them is low, and there is a steep price to keeping students out of school, shuttering restaurants and retail shops and stopping travel and commerce.” But she urged people to get booster shots, recommended that they wear KN95 or N95 masks and encouraged governments and businesses to mandate vaccination. All of those measures can reduce the spread of Covid and, by extension, hospital crowding and death.
What about elderly or immunocompromised people, who have been at some risk of major Covid illness even if they’re vaccinated? Different people will make different decisions, and that’s OK. Severely immunocompromised people — like those who have received organ transplants or are actively receiving cancer treatment — have reason to be extra cautious. For otherwise healthy older people, on the other hand, the latest data may be encouraging enough to affect their behavior. … Before Omicron, a typical vaccinated 75-year-old who contracted Covid had a roughly similar risk of death — around 1 in 200 — as a typical 75-year-old who contracted the flu. … Omicron has changed the calculation. Because it is milder than earlier versions of the virus, Covid now appears to present less threat to most vaccinated elderly people than the annual flu does. The flu, of course, does present risk for the elderly. And the sheer size of the Omicron surge may argue for caution over the next few weeks. But the combination of vaccines and Omicron’s apparent mildness means that, for an individual, Covid increasingly resembles the kind of health risk that people accept every day.
David Leonhardt, New York Times Morning Newsletter, January 5, 2022, Omicron Is Milder
The medical/scientific view was more cautious about Omicron. Within a few months, other Omicron lineages were recognized. A web page published by Johns Hopkins University discussed breakthough infections of omicron variants, and the known risks:
A variant of concern has been observed to be more infectious, and is more likely to cause breakthrough infections or reinfections in those who are vaccinated or previously infected. These variants are more likely to cause severe disease, evade diagnostic tests, or resist antiviral treatment. Alpha, beta, gamma, delta and omicron variants of the SARS-CoV-2 coronavirus are classified as variants of concern.
A variant of high consequence is a variant for which current vaccines do not offer protection. As of now, there are no SARS-CoV-2 variants of high consequence.
….
In November 2021, a variant of the SARS-CoV-2 coronavirus emerged and was named omicron by the WHO, which lists it as a variant of concern. Cases of the highly contagious variant, including a subvariant called BA.2, or “stealth omicron,” have caused surges of COVID-19, particularly in areas where safety precautions have been relaxed. “The omicron variant is responsible for the largest surge since 2019,” says Maragakis. “Omicron has a large number of mutations that all appeared at once. It’s very different from previous versions, including delta. It has over 50 mutations, many in the spike protein, which is how it gets into our cells in the first place. The spike protein is also one of the most prominent exterior features of the virus that our immune system recognizes, responds to and uses to develop antibodies. Unfortunately, omicron is a perfect storm: Mutations gave it the ability to escape weak immune responses AND become more transmissible from person to person.”
Omicron and BA.2: Do they cause more severe illness? Bollinger says, “The answer appears to be no. In fact, there is evidence that omicron may cause less severe disease than the delta variant.” “What we see is that omicron may have more of an affinity for our upper airways than our lower airways, and can be more easily spread through talking, coughing or breathing, especially from people without masks on. Omicron also may have more potential for airborne aerosolization of the virus, hanging in the air in indoor settings,” Maragakis says.
Are omicron and BA.2 more contagious than other variants of the coronavirus? Omicron and especially its subvariant, BA.2, are very contagious, more so than the original coronavirus or the delta variant.
….
“In the meantime, we need to continue all of our efforts to prevent viral transmission, by practicing safety precautions, vaccinating as many people as possible as soon as we can and encouraging boosters among those who are eligible,” says Bollinger. Ray concurs. “Vaccines and boosters are the medical miracle of 2020, but we also need to reemphasize basic public health measures. We have tools at hand that enable individuals to manage risk, including wearing high-quality masks or respirators. Those rated FFP2 or FFP3 are more protective than cloth masks, and often easier to wear. Hand-washing and avoiding large indoor gatherings, especially with unmasked people, are other ways to mitigate the risk of infection.” Maragakis says, “The basics work, and everyone should be aware that anyone can have this virus now. If you get yourself into that mindset and act accordingly, then if you get that call that someone you know is positive, if you’ve been vigilant, you can know you’re safer.”
Canada’s bold decision to delay and mix doses of COVID-19 vaccines led to strong protection from hospitalization and death, but the emergence of Omicron and its subvariants rendered them less protective against infection than previous virus strains.
….
…. new study … published in Clinical Infectious Diseases, that showed two doses of mRNA vaccines or AstraZeneca “gave substantial and sustained protection” against hospitalization from Delta, up to November 2021.
….
While vaccine effectiveness against severe outcomes has held up well, two-dose protection against Omicron infection fell dramatically in December, dropping to just 36 per cent, according to one Ontario preprint study, with boosters raising it to 61 per cent. That significant hit to our population immunity underscored the need for boosters and left us highly susceptible to Omicron-fuelled fifth and sixth waves that have since ripped through the population.
The CBC addressed Omicron variants/subvariants in another “Second Opinion” post:
“Let’s be honest, the virus is in control here, not us,” said Dr. Michael Gardam, an infectious diseases physician, medical director of infection prevention and control at Women’s College Hospital in Toronto and CEO of Health PEI. “We’re entirely at the whim of whatever random evolutionary events occur and it’s really hard to predict.”
….
Tulio de Oliveira, the director of South Africa’s Centre for Epidemic Response and Innovation, said South Africa has had a high level of population immunity with over 90 per cent estimated to have been previously infected, vaccinated or both. “That’s one of the reasons why we believe that the big Omicron wave that we had didn’t translate to a very high number of hospitalizations and deaths,” he said. “And BA.2, despite emerging and going on to dominate all the infections in South Africa, did not translate into an uptick of infection, which was very different in Europe, where they had a BA.1 wave followed by a BA.2 wave.” That double whammy of Omicron’s BA.1 and BA.2 hit Canada hard as well, fuelling a devastating fifth wave late last year that subsided right as BA.2 sparked a smaller sixth wave in April — but it also drove up our levels of population immunity. “It gives you a sense that the more people who are infected with this and are vaccinated, the better you are at weathering it,” said Gardam. “The hope is it starts to become like the other coronaviruses that infect us every year that cause colds … and eventually it’s pretty hard for the virus to come up with something so novel that you haven’t seen part of it before.”
As a result, Omicron and its subvariants completely changed Canada’s immunity landscape over the past few months. Previously, Canada was more in line with a country like South Korea given our high vaccination rates and previously low levels of prior infection, de Oliveira said, with much of the country seeing relatively low levels of COVID throughout the pandemic. With Omicron, we were more similar to countries like South Africa and the U.S. with much higher levels of population immunity — but our high vaccination rate protected us. “What that means is that potentially as new variants and subvariants of Omicron emerge … that may translate in a relatively high number of infections, but potentially not in a very high rate of hospitalization and death,” he said. “Look at wave one, it was a very small wave but there were a lot of hospitalizations,” said Gardam. “Then finally Omicron hit and the spike in infections was insane, but the death rate never got as high as it did in earlier waves. So we are getting better at fighting this off.”
Adam Miller, CBC News, Second Opinion column, April 30, 2022, What could ‘COVID season’ actually look like, New variants, waning immunity make it hard to predict when the next wave will hit .
The USA
NBC News discussed remarks by Dr. Anthony Fauci, director of the USA National Institute of Allergy and Infectious Diseases April 27, 2022:
“Namely, we don’t have 900,000 new infections a day and tens and tens and tens of thousands of hospitalizations and thousands of deaths. We are at a low level right now,” he said. In comments Wednesday to The Washington Post, however, Fauci seemed to clarify his earlier remarks, saying that unlike the “full-blown explosive pandemic phase” during the brutal winter omicron surge, he was describing what appears to be a period of transition toward the coronavirus becoming an endemic disease. “The world is still in a pandemic. There’s no doubt about that. Don’t anybody get any misinterpretation of that. We are still experiencing a pandemic,” Fauci told the Post.
….
U.S. cases are far lower than they were in recent months. But health officials are keeping a close eye as highly contagious variants continue to spread. The Centers for Disease Control and Prevention says cases have risen about 25% in the past week. Meanwhile, Fauci decided not to attend Saturday’s White House Correspondents’ Association dinner amid concerns about COVID-19, telling The New York Times on Tuesday that his decision was based on “my individual assessment of my personal risk.”
The media began to mention “stealth Omicron”, the Omicron subvariant BA.2 which was more contagious than B.1.1.529, and more virulent, and other subvariants, . By early May 2022, Omicron variant BA 2.12.1 was the source of 43% of new infections in the USA. May 12, 2022, the news media reported “U.S. surpasses 1 million COVID-19 deaths: A look at the numbers“.
On May 16, 2022, Apoorva Mandavilli , writing in the New York Times “Daily Covid Briefing” addressed the implications of Covid-19 becoming endemic, noting:
This is not how it was supposed to be. Earlier in the pandemic, experts thought that immunity from vaccination or previous infection would forestall most reinfections. The Omicron variant dashed those hopes. Unlike previous variants, Omicron and its many descendants seem to have evolved to partially dodge immunity. That leaves everyone — even those who have been vaccinated multiple times — vulnerable to multiple infections. “If we manage it the way that we manage it now, then most people will get infected with it at least a couple of times a year,” said Kristian Andersen, a virologist at the Scripps Research Institute in San Diego. “I would be very surprised if that’s not how it’s going to play out.”
The new variants have not altered the fundamental usefulness of the Covid vaccines. Most people who have received three or even just two doses will not become sick enough to need medical care if they test positive for the coronavirus. And a booster dose, like a previous bout with the virus, does seem to decrease the chance of reinfection — but not by much.
At the pandemic’s outset, many experts based their expectations of the coronavirus on influenza, the viral foe most familiar to them. They predicted that, as with the flu, there might be one big outbreak each year, most likely in the fall. The way to minimize its spread would be to vaccinate people before its arrival. Instead, the coronavirus is behaving more like four of its closely related cousins, which circulate and cause colds year round. While studying common-cold coronaviruses, “we saw people with multiple infections within the space of a year,” said Jeffrey Shaman, an epidemiologist at Columbia University in New York. If reinfection turns out to be the norm, the coronavirus is “not going to simply be this wintertime once-a-year thing,” he said, “and it’s not going to be a mild nuisance in terms of the amount of morbidity and mortality it causes.”
BA.2.12.1 is quite distinct from Omicron BA.1 and BA.2. … there is a key, unique mutation L452Q. The other important Omicron subvariants currently, BA.4 and BA.5, have multiple different mutations (including L452R, F486V and R493Q) from BA.2, and account for the new wave of cases in South Africa, and more recently in Portugal, and have just been labelled as VoC (variants of concern) by the European Centre for Disease Prevention and Control. Both BA.2.12.1 and BA.4/BA.5 pose a further challenge to our immune system recognition, with minimal cross-immunity derived from BA.1.
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… now multiple Omicron subvariants are outcompeting one another, predominantly because of more immune evasion, such that BA.2 with 30% more transmission overtook BA.1, and BA.2.12.1 (in parallel to BA.4 and BA.5) has a substantial transmission advantage over BA.2. …
… a breakdown of protection from transmission occurred with Omicron with “breakthroughs” in people with vaccination occurring quite commonly. That, and reinfections, were an unusual phenomenon (~1%) before Omicron. Now we are seeing people with 4 shots who are getting breakthrough infections, even at 1-2 weeks from their most recent shot, when there should be the maximal level of neutralizing antibodies induced. That’s not a good sign, relative to the 95% vaccine effectiveness we had against symptomatic infections against the ancestral, D614G, Alpha, and Delta (with a booster) strains.
… we have relied (and taken for granted) on vaccines to protect us from severe disease—to prevent hospitalizations and deaths. Prior to Omicron we could, with a booster, assume there was well over 90-95% vaccine effectiveness vs severe disease. It is clear, however, from multiple reports … that this level of protection has declined to approximately 80%, particularly taking account the more rapid waning than previously seen. That represents a substantial drop-off …
… we have a highly unfavorable picture of: (1) accelerated evolution of the virus; (2) increased immune escape of new variants; (2) progressively higher transmissibility and infectiousness; (4) substantially less protection from transmission by vaccines and boosters; (5) some reduction on vaccine/booster protection against hospitalization and death; (6) high vulnerability from infection-acquired immunity only; and (7) likelihood of more noxious new variants in the months ahead.
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During the Delta wave in the United States, vaccinated individuals accounted for 23 per cent of the deaths, whereas this nearly doubled to 42 per cent during the Omicron wave. This is attributable to waning of protection, lack of boosters, and the diminished protection against Omicron (BA.1).
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While the policy of zero Covid is untenable with Omicron … we should adopt the new policy of Zero Covid Deaths. This is diametrically opposed to Covid capitulation. This builds, in part, on the tools that we already have, knowing that the vast majority of deaths occur in people age 60 plus (92% of US hospitalizations have been in people age 50+). All such people need to have vaccination and booster coverage but our CDC has failed to convey their life-saving impact from the get go, a veritable booster botch job … we have 31% of Americans who had had 1 booster shot whereas most peer countries are double that proportion. And why we rank 60th in the world’s countries for boosters, and especially poorly among older Americans compared (<65%, age 60+) with many Western Europe and Asian Pacific countries (~85-90%). That doesn’t even speak to the need for a 4th dose in this high-risk group or that lack of intensive monitoring of our 7 million immunocompromised people who are not getting help to guide their protection with assay of neutralizing antibodies, or receiving Evusheld monoclonal antibody preventive protection. But well beyond the use of boosters and vaccines, and easy, rapid access to Paxlovid, we absolutely need an aggressive stance to get ahead of the virus—for the first time since the pandemic began—instead of surrendering. That means setting priorities, funding, and the realization, unfortunately, that the pandemic is far from over.
… The CDC’s [Center for Disease Control] current guidelines effectively say that Americans can act as if COVID is not a crisis—until hospitalizations reach a high enough threshold. The country still may be heading to that point. Hospitalizations are climbing in 43 states, especially in the Northeast. In Vermont, the rate of new admissions has already neared the peak of the recent Omicron surge. Earlier this month, “three different emergency-room docs said this is by far the worst that COVID has been at any point,” Tim Plante, an internist at the University of Vermont, told me. “They’re bewildered that it’s happening again.” Meanwhile, people in most of New York City are now advised to mask indoors again, after rising hospitalizations triggered the CDC’s “high” alert level.
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America’s current pandemic strategy is predicated on the assumption that people can move on from COVID, trusting that the health-care system will be ready to hold the line. But that assumption is a fiction. Much of the system is still intolerably stressed, even in moments of apparent reprieve. And the CDC’s community guidelines are set such that by the time preventive actions are triggered, high levels of sickness and death will be locked in for the near future. For many health-care workers, their mental health and even their commitment to medicine are balanced on a precipice; any further surges will tip more of them over. “I feel like I’m holding on by a thread,” Marina Del Rios, an emergency physician at the University of Iowa, told me. “Every time I hear a new subvariant is coming along, I think: Okay, here we go.”
The journalist David Leonhardt argued, in the New York Times Morning Newsletter, that people could mask themselves but that mask mandates should end:
From the beginning of the pandemic, there has been a paradox involving masks. … Masks reduce the spread of the Covid virus by preventing virus particles from traveling from one person’s nose or mouth into the air and infecting another person. Laboratory studies have repeatedly demonstrated the effect.
In U.S. cities where mask use has been more common, Covid has spread at a similar rate as in mask-resistant cities. Mask mandates in schools also seem to have done little to reduce the spread. Hong Kong, despite almost universal mask-wearing, recently endured one of the world’s worst Covid outbreaks.
… the effect of vaccines on severe illness is blazingly obvious in the eographic data: Places with higher vaccination rates have suffered many fewer Covid deaths. The patterns are clear even though the world is a messy place, with many factors other than vaccines influencing Covid death rates.
The idea that masks work better than mask mandates seems to defy logic. … The main explanation seems to be that the exceptions often end up mattering more than the rule. The Covid virus is so contagious that it can spread during brief times when people take off their masks, even when a mandate is in place.
At the start of the vaccination campaign, getting dosed up was relatively straightforward. In the United States, a pair of Pfizer or Moderna shots (or just one Johnson & Johnson), then a quick two-week wait, and boom: full vaccination, and that was that. The phrase became a fixture on the CDC website and national data trackers; it spurred vaccine mandates and, for a time in the spring and summer of 2021, green-lit the immunized to doff their masks indoors.
Then came the boosters. Experts now know that these additional shots are essential to warding off antibody-dodging variants such as the many members of the Omicron clan. Some Americans are months past their fifth COVID shot, and the nation’s leaders are weighing whether vaccinated people will need to dose up again in the fall. To accommodate those additions, the CDC has, in recent public communications, tried to shift its terminology toward “up to date.” Katelyn Jetelina, an epidemiologist at the University of Texas Health Science Center at Houston, prefers that phrase, because it “allows for flexibility” as recommendations evolve. It also more effectively nods at the range of protection that vaccination affords, depending on how many doses someone’s gotten and when their most recent dose was.
But fully vaccinated has been hard to shake, even for the CDC. The agency, which did not respond to requests for comment, maintains that the original definition “has not changed,” and the term still features heavily on CDC websites. Maybe part of the stubbornness is sheerly linguistic: Up to date means something different to everyone, depending on age, eligibility, health status, and vaccine brand. Fully vaccinated is also grabby in a way that up to date is not. It carries the alluring air of completion, suggesting that “you’re actually done with the vaccine series,” maybe even the pandemic overall, Jessica Malaty Rivera, an epidemiologist and adviser at the Pandemic Prevention Institute, told me. All of this may be partly why that uptake of boosters—which sound optional, even trivial, compared with the first two shots—remains miserably low in the U.S.
Today, an advisory committee to the FDA recommended that our current slate of shots be updated to include a piece of an Omicron subvariant, with the aim of better tailoring the vaccine to the coronavirus variants that could trouble us this fall. Neither the agency nor its outside expert panel has yet reached consensus on which version of Omicron will be the best choice, and whether the next round of shots will still contain the original version of the virus as well. Regardless, a new formulation with any bit of Omicron will constitute a bet that these ingredients will better protect people than another dose of the original vaccine recipe, whose protective powers have been fading for many months.
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Here in the U.S., vaccine enthusiasm has a pretty dire prognosis. Fewer than half of the vaccinated Americans eligible for a first booster have opted for one; an even paltrier fraction of those who could get second and third boosters are currently up to date on their shots. Among high-income countries, the U.S. ranks embarrassingly low on the immunity scale—for a nation with the funds and means to holster shots in spades, far too many of its residents remain vulnerable to the variants sweeping the globe, and the others that will inevitably come.
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From the beginning, the messaging on COVID boosters has been a bungled mess. Originally, it seemed possible that a duo of doses, perhaps even a single shot, would be enough to block all infections, and bring pandemic precautions to a screeching halt. That, of course, was not the case. With the virus still spreading last summer and fall, experts began heatedly debating what purpose extra doses might serve, and who should get them—and if they were needed at all. Caught in the cross fire, the FDA and CDC issued a series of seemingly contradictory communications about who should be signing up for extra shots and when.
… By the end of 2021, the U.S. had a catchall booster recommendation for adults (and has since expanded it to kids as young as 5), but whatever the benefit of a booster might be, much of the public had disengaged. …
The shots have also become much harder to get. Mass vaccination sites have closed, especially affecting low-income and rural regions, where there’s a dearth of medical centers and pharmacies. Pandemic funds have dried up, imperiling shot supply. Ever-changing recommendations have also created an impossible-to-navigate matrix of eligibility. Since the booster rollout began, recommendations on when to boost and how many times have shifted so often that many people haven’t realized the shots were actually available to them, or were mistakenly turned away from vaccination sites that couldn’t parse the complex criteria dictating who was allowed an extra dose.
… Once more, the ever-changing coronavirus behind COVID-19 is assaulting the United States in a new guise—BA.5, an offshoot of the Omicron variant that devastated the most recent winter. The new variant is spreading quickly, likely because it snakes past some of the immune defenses acquired by vaccinated people, or those infected by earlier variants. Those who have managed to avoid the virus for close to three years will find it a little harder to continue that streak, and some who recently caught COVID are getting it again. …
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The age of Omicron began shortly after Thanksgiving [November in the U.S.A.], as the new variant swept through the U.S., ousting its predecessor, Delta. That initial version of Omicron, now known as BA.1, was just the first of a mini-dynasty of related variants that have since competed against one another in a grim game of succession. BA.2 took over from BA.1, and caused a surge in the spring. BA.4 and BA.5 are spreading even more quickly: First detected in South Africa in January and February, they have since displaced BA.2 all over the world, leading to surges in both cases and hospitalizations. In the U.S., BA.5 now accounts for about 54 percent of all COVID infections, and BA.4, about another 17 percent. (Most of this article will deal with BA.5 alone because it already seems to be outcompeting its cousin.)
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When people are vaccinated or infected, they develop antibodies that can neutralize the coronavirus by sticking to its spike proteins—the studs on its surface that the pathogen uses to recognize and infect our cells. But BA.4 and BA.5 have several mutations that change the shape of their spikes, which, like swords that no longer fit their sheaths, are now unrecognizable to many antibodies that would have disarmed older variants. That’s why, as many studies have now consistently shown, antibodies from triple-vaccinated people, or people who had breakthrough infections with earlier variants, are three to four times less potent at neutralizing BA.4 or BA.5 than BA.1 or BA.2. This means that most people are now less protected against infection than they were two months ago—and that some people who got COVID very recently are getting reinfected now. …
On August 16, 2022 The Atlantic published an article on revised CDC guidance in the USA:
Americans have been given the all clear to dispense with most of the pandemic-centric behaviors that have defined the past two-plus years—part and parcel of the narrative the Biden administration is building around the “triumphant return to normalcy,” says Joshua Salomon, a health-policy researcher at Stanford. Where mitigation measures once moved in near lockstep with case numbers, hospitalizations, and deaths, they’re now on separate tracks; the focus with COVID is, more explicitly than ever before, on avoiding only severe illness and death. The country seems close to declaring the national public-health emergency done—and short of that proclamation, officials are already “effectively acting as though it’s over,” says Lakshmi Ganapathi, a pediatric-infectious-disease specialist at Boston Children’s Hospital. If there’s such a thing as a “soft closing” of the COVID crisis, this latest juncture might be it.
The shift in guidelines underscores how settled the country is into the current state of affairs. This new relaxation of COVID rules is one of the most substantial to date—but it wasn’t spurred by a change in conditions on the ground. A slew of Omicron subvariants are still burning across most states; COVID deaths have, for months, remained at a stubborn, too-high plateau. The virus won’t budge. Nor will Americans. So the administration is shifting its stance instead. No longer will people be required to quarantine after encountering the infected, even if they haven’t gotten the recommended number of shots; schools and workplaces will no longer need to screen healthy students and employees, and guidance around physical distancing is now a footnote at best.
After the W.H.O. began promoting the 70 percent vaccination goal [mid 2021], many lower-income governments adopted the target for their own populations. The Biden administration also endorsed it last September, setting a deadline of September 2022.
At the time, two doses of the vaccines from Pfizer and Moderna were understood to offer very strong protection against even mild disease, and there was still hope that achieving high levels of vaccination coverage would tame the virus. But the emergence of new variants and the spread of the virus in Africa changed the calculus.
The vaccine regimens that had been planned for the developing world offered little protection against infection with the Omicron variant. And as sub-Saharan African countries were shut out of vaccine distribution for much of last year, more and more Africans gained protection against the virus from natural infection, which studies have shown works as well as two mRNA doses in preventing infection. New data from the W.H.O. shows that at least two-thirds of Africans had been infected with the virus before the Omicron wave.
“Prior increases of infections, in different waves of infection, have demonstrated that this travels across the country,” Rochelle Walensky, the [USA] CDC director, said at a White House briefing with reporters.
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The pandemic is now two and a half years old. And the U.S. has seen — depending how you count them — five waves of COVID-19 during that time, with the later surges driven by mutated versions of the coronavirus. A fifth wave occurred mainly in December and January, caused by the Omicron variant, which spread much more quickly than earlier versions.
Some experts are worried the country now is seeing signs of a sixth wave, driven by an Omicron subvariant. On Wednesday, Walensky noted a steady increase in COVID-19 cases in the past five weeks, including a 26 per cent increase nationally in the last week.
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Officials said they are concerned that waning immunity and relaxed mitigation measures across the country may contribute to a continued rise in infections and illnesses. They encouraged people — particularly older adults — to get boosters.
June 15, 2022 the British news source the Guardian reported:
Although BA.2 continues to account for the bulk of UK infections, data from the Office for National Statistics up to 2 June suggests that Covid cases may be starting to rise again in England and Northern Ireland, driven by an increase in BA.4 and BA.5 infections. The trends were uncertain in Wales and Scotland. Also gaining ground in the UK are BA.5.1 (a child of BA.5), and the BA.2.12.1 subvariant (the USA’s dominant Covid strain), which the UK Health Security Agency is monitoring.
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… scientists had hoped that high levels of immunity from recent infection with BA.2 and booster vaccines might be enough to prevent these newer variants from gaining a significant foothold here … with immunity from third vaccine doses waning in most population groups, and only the over-75s, and extremely vulnerable groups having been offered “spring booster” doses, this cannot be guaranteed. Neither is recent infection with the BA.1 or BA.2 Omicron variants necessarily protection against reinfection with BA.4 or BA.5.
According to research published in Science on Tuesday, natural infection with Omicron doesn’t produce a strong immune response, regardless of whether scientists look at antibodies or T-cells – meaning that people who have already recovered from an Omicron infection can quickly become reinfected. The findings, from Prof Danny Altmann at Imperial College London and colleagues, may help to explain why infection levels have remained high in countries such as the UK, despite so many already having been infected with it.
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It also put paid to the idea that the virus is on the verge of merely turning into common cold. “It clearly isn’t, and there’s no pressure on it to do that, really,” said Griffin.
Even so, the rise of BA.4/5 and other subvariants by no means puts us back to square one. The UK’s population is, by and large, highly vaccinated, and previous infection with other variants will also count for something. Those who haven’t been vaccinated remain vulnerable, however.
Data released by Britain’s Office for National Statistics showed that more than three million people in the U.K. had COVID-19 last week, although there has not been an equivalent spike in hospitalizations. The number of COVID-19 deaths also fell slightly in the last week. “COVID-19 has not gone away,” said Dr. Mary Ramsay, of the Health Security Agency. “It is also sensible to wear a face covering in crowded, enclosed spaces,” she said. Britain dropped nearly all its coronavirus measures, including mask-wearing and social distancing, months ago and masks are rarely seen on public transport. The latest jump in coronavirus cases comes after an earlier increase of about 40 per cent last month, following the large street parties, concerts and festivities held as part of Platinum Jubilee celebrations marking 70 years of Queen Elizabeth’s reign.
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British officials said the latest wave of COVID-19 infections was likely caused by Omicron subvariants BA.4 and BA.5. Omicron has tended to cause a milder disease than previous variants like Alpha or Delta, but scientists warn its ability to evade the immune system means that people may be more susceptible to being reinfected, including after vaccination. Despite widespread immunization across Britain, the protection from vaccines is likely fading and Omicron and its subvariants have evolved to become more infectious. Britain’s Health Security Agency said they were seeing more outbreaks in care homes for older people and a rise in admissions to intensive care units of people older than 65.
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Globally, the World Health Organization said this week that COVID-19 is increasing in more than 100 countries. The UN health agency warned that relaxed testing and surveillance measures mean it may be more difficult to catch emerging variants before they spread more widely.
By April 2022 the Omicron variant or subvariants had been detected in people in China. By the end of April the Chinese government had locked down Shanghai, Changchun, Jilin, parts of Beijing, and other cities, straining global supply chains, reported by the Associated Press and CBC World under the headline China manufacturing weakens further as lockdowns continue. The Omicron variant(s) spread in other East Asian countries:
The Covid-19 pandemic initially did not cause large numbers of infections in the 3 Canadian Prairie Provinces. Restrictions on travel isolated residents from infections. The governments were slow to impose other restrictions. Winters on the prairies are cold, and life moves indoors. The Prairie Provinces had increased rates of infection and hospitalizations in the winter 2020-21 The Prairie Provinces delayed taking further non-pharmaceutical measures. Provincial politicians blamed the federal government and even foreign governments for lack of preparation and delay in taking measures to mitigate the effects if the pandemic. On February 7, 2022 Saskatchewan became the first province to stop daily reporting of Covid-19 statistics, and report its Covid-19 data weekly. Manitoba followed in late March:
COVID hospitalization and death numbers, meanwhile, will only be reported once a week due to public health’s determination that COVID-19 is in the process of becoming an endemic disease. “Real-time data is less critical with endemic reporting. Instead, we would shift our focus to key pieces of information that will provide the most relevant epidemiological evidence and data for both the public and for decision makers,” said Dr. Jazz Atwal, Manitoba’s deputy provincial public health officer, on March 2. “Manitobans will see this shift in the days ahead as we focus on reporting on key trends, more vulnerable settings and other important indicators of COVID activity and severity in our province. Information about COVID will continue to be transparent and publicly available, but this is a part of a response that has to shift as well.”
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Dr. Brent Roussin, the chief provincial public health officer, has stated it is up to individuals to make that determination on their own. “We’ve been able to change our approach from strict public health measures to public health recommendations. That guidance is now available online to help support people in their own decision making to assess their level of risk when it comes to things like mask wearing, physical distancing and how many people are comfortable gathering along with,” Roussin said on March 16.
Conservative (including neo-liberal and libertarian) residents of the Prairie Provinces had embraced the paranoid style of American populism long before Trumpism. Canadian prairie conservatives have been suspicious of “liberal” media, and elites conspiring to harm or exploit “common people” and deprive them of their freedom and comforts since the 1970s – and much longer. Conservative politicians on the Canadian Prairies have a history of distrusting the public service and controlling the narrative. Brian Pallister, the leader of the Manitoba Conservative party 2018-2021 was responsive to rural sentiment, business interests and anti-government rhetoric. He became embattled. At one point Pallister had complained, for some reason (populist elite-bashing?), that doctors were paid by the government. Pallister, like the coach or manager of a failing sports team, resigned.
Only a few members of the public accessed the dashboards and daily data reports. Dashboards did not work like a weather forecast or a map. Not even the most expert individuals were able to use the published data to make decisions to avoid risks about visiting the places there wanted to go. In the early stages of the pandemic when the original virus and the virulent variants were in the population the data legitimized NPIs, self-isolation, remote work and the use of the internet (Zoom, Teams) for meetings, and individuals to comply with NPIs until pandemic fatigue became overwhelming.
Public health officials shifted to maintaining that public health was a matter of making decisions about personal risk when the dashboards became a source of information that could be used to criticize public health officials and public officials. In early 2022, public health officials in the western Canadian Prairie Provinces said that Covid-19 (Omicron) was:
an endemic illness,
a mild illness; and
people should live with it.
The stories were embraced by the renewed Conservative Manitoba government, business interests, and Canadian Conservative political leaders including Doug Ford in Ontario.
For the next 3 months the CBC in BC reported the BC Centre for Disease Control (“BCCDC”; BC government) weekly reports. The statistic of rates of infection were based on lab tests. The CBC published other articles until mid-May, including weekly health columns called Second Opinion (“SO”), by Adam Miller, based on a CBC Health newsletter by Adam Miller:
BC gambled that infections would decline in the spring and summer, and that the endemic illness was less severe than the illness caused by original virus. The government made some self-test kits available to the public, but the self-test results were not included in statistics. 2nd vaccine boosters (4th shots) have been administered to or made available to nursing home residents, persons over 70, First Nations elders and some individuals.
The CBC, like the privately owned media, sang the chorus to the song chosen by public health officials and politicians, that might be titled, like the song by the American folksinger Bob Franke, Alleluia the Great Storm is over.
On Wednesday, the province’s chief medical officer of health announced most mask mandatory mask rules will expire Saturday, including on transit and in hospitals. Masks will still be required in Ontario long-term care homes and retirement homes after Saturday.
Dr. Fahad Razak, the new scientific director of Ontario’s COVID-19 science advisory table, told CBC Radio’s Metro Morning the provincial requirement could have been extended for at least four more weeks to help relieve some of the pressure on hospitals that will now have to enforce their own mask rules. “I’m heartened to see many hospitals have already announced that they will continue to require them,” Razak said Thursday. “I suspect you’ll see most institutions will require it.”
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Dr. Kieran Moore, the province’s chief medical officer of health, said Wednesday that he made the decision based on high vaccination rates and improvements in the provincial COVID-19 situation. Provincial masking requirements in areas such as public transit, health care settings, long-term care homes and retirement homes were initially set to expire on April 27, but that deadline was extended earlier this year to June 11. “The province will continue to monitor for any significant changes, including any new variants of concern, to ensure we are adapting our response to protect the health and safety of all Ontarians,” he said. Rules requiring that people wear masks on public transit and most health-care settings will expire at 12 a.m. on Saturday. Mask requirements lifted in most other settings in March, along with essentially all other public health measures aimed at stemming the spread of COVID-19 in the province. Masks are still “strongly recommended” in high-risk congregate settings like group homes and shelters, his statement said.
The province has said organizations can make their own mask policies, and that people should keep masking if they are high-risk for the illness, are recovering from COVID-19, have symptoms or have been in contact with someone who has the illness. Directives around mask requirements for health workers will also expire on Saturday and be replaced by Health Ministry guidance outlining when masks should be worn in hospitals and other health workplaces.
The next day, CBC Canada published an article suggesting abandoning the remaining vaccine mandates:
The waning effectiveness of vaccines to stop the spread of the highly infectious Omicron variant of COVID-19 could mean it’s time for federal policy makers to consider lifting vaccine mandates, some experts suggest. “It’s hard to really justify our mandates anymore,” said Dr Zain Chagla, an infectious diseases physician at St. Joseph’s Healthcare Hamilton and an associate professor at McMaster University. Toronto’s Pearson International Airport has recently been a scene of snarling air passenger traffic, causing long lineups and major delays.
While government officials have blamed staffing shortages for problems, some industry groups and politicians are laying the blame on COVID-related border restrictions including vaccine mandates that require travellers to prove their vaccine status using an app before entering Canada.While government officials have blamed staffing shortages for problems, some industry groups and politicians are laying the blame on COVID-related border restrictions including vaccine mandates that require travellers to prove their vaccine status using an app before entering Canada.
Scientists stress that the vaccines do hold up against what matters — severe illness, hospitalization and death. And Chagla said that when the Alpha and Delta variants of COVID-19 swept through, data showed that vaccination had a “profound effect” on stopping a significant amount of infections, and that people’s ability to transmit was reduced. Last month, in a editorial for The Globe and Mail, under the headline: “The logic behind vaccine mandates for travellers no longer holds,” Chagla wrote that with the Omicron variant, vaccine efficacy “wanes significantly” to help prevent transmission. He pointed to data from the UK Health Security Agency that he said showed the effectiveness of two or three doses of vaccine against spreading the Omicron-variant infection over time approaches zero.
… Dr. Nazeem Muhajarine, professor of community health and epidemiology at the University of Saskatchewan in Saskatoon, said that some research does indicate that vaccine booster doses do protect people from transmission of the virus. That’s why he believes “this last remaining vaccine policy should remain a little longer because the threat of COVID-19 and the harm it causes in terms of long COVID, deaths and hospitalization particularly in vulnerable people, elderly and in some cases in children hasn’t entirely disappeared.”
Yet, Dr. Amesh Adalja, an infectious disease physician and senior scholar at the Johns Hopkins Center for Health Security in Baltimore, questioned the value those mandates now serve in light of the Omicron variant and population immunity. “I think that increasingly it’s become less valuable than it was in the earlier eras in the pandemic, because the vaccine in the face of Omicron isn’t very great at protecting against infection, he said. Because the vaccines hold up against severe illness, hospitalization and death, Adalja said there is still great value for employers to insist their workforce be vaccinated from a work-safety standpoint. As for vaccine mandates for travel, “I think it has much less value,” he said. “I don’t think the ArriveCan [app] serves the same value that it once did.”
Appearing before a House of Commons health committee earlier this week,Canada’s Chief Public Health Officer Dr. Theresa Tam said the mandates were first implemented when there was a strong resurgence of the Delta variant and two doses of vaccines were very effective. But Omicron was the “game changer,” she said. “Given the reduced vaccine effectiveness, even with three doses against the Omicron variant, vaccines cannot prevent all transmissions alone,” she said. “So a layered approach has to be considered, including layering mask wearing, for instance. But these are the things that the relevant ministers need to consider.”
May 25, 2022, the media were reporting that Covid-19/Omicron infections in BC were disrupting work across the economy: “COVID-19 continues to cause worker absences in many B.C. sectors“. The weekly story May 26, 2022 reporting the public data reports said:
Much of the provincial data, which includes cases, hospital admissions and deaths and is at least five days old, is in weekly reports from the B.C. Centre for Disease Control (BCCDC).
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The province is reporting 1,358 new cases between May 15 and 21, based solely on positive PCR tests, for a total of 370,559 cases to date. That represents a decline of 17 per cent from the previous week’s retroactive case count of 1,644. However, because PCR testing is quite limited, the BCCDC points out the weekly case counts likely underestimate the actual number of cases. Numerous organizations in B.C., including B.C. Ferries, are reporting staff shortages due to the spread of the virus.
The number of people testing positive has seen a slight dip across the province. A total of 8.6 per cent of all PCR tests came back positive in B.C. as of May 21, compared to 9.7 per cent the previous week. Positivity rates vary across the province, with 14.9 per cent on Vancouver Island and 6.7 per cent in the Vancouver Coastal Health Authority.
The CBC continued to comment on risk and risk control measures, but the material was in individual radio shows and CBC podcasts. Brian Goldman, the host of the medical podcast, White Coat, Black Art hosted a podcast interview published an episode of the related podcast, The Dose, June 15, 2022, as mask mandates in Ontario were terminated: What should I do when the mask mandates are lifted? In late June 2022, CBC health columnist/reporter Adam Miller wrote:
Canada is once again a hotbed for variants, with BA.2.12.1 now making up more than 40 per cent of COVID cases, while BA.4 and BA.5 are quickly gaining ground at more than 10 per cent combined in late May — a major jump from less than one per cent weeks earlier. But the latest available federal data is weeks out of date and modelling experts CBC News spoke to estimate the true proportion of BA.4 and BA.5 cases is more than 20 per cent — and could be as high as 50 — with one of them likely to become dominant in the coming weeks. “COVID-19 has shown us over the past few years that there may be more surprises ahead,” Canada’s Chief Public Health Officer Dr. Theresa Tam said during a press conference Friday. “The virus is still circulating in Canada and internationally and factors such as viral evolution and waning immunity are anticipated to impact COVID-19 activity moving forward.”
“Omicron has evolved and it’s so much different than our vaccines and infections prior to Omicron — the type of immunity that you got is just a different beast,” said Sarah Otto, an expert in modelling and evolutionary biology at the University of British Columbia. “And so what we’re seeing with vaccine protection is that it’s not so much the number of doses as it is how recent your last dose has been, and I think that’s because the neutralizing antibodies in our bloodstream, they’re not recognizing the virus as well.”
That’s why virologists and immunologists say timing our next shots ahead of another potential wave or when new variants start to rise in Canada is so important, so we don’t get caught scrambling to roll out doses in the midst of a rapidly worsening wave — like when Omicron first hit in December.
BC’s public optimism changed to concern that the situation was changing with notes of concern about the anxiety of some members of the public:
Fourth doses, the province says, are currently only available to … people age 70 and older, Indigenous people over 55, and people in long-term care — six months after their last booster..
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With just two per cent of British Columbians fully vaccinated and boosted, the province is near last place among provinces when it comes to uptake for fourth COVID-19 vaccine doses, ahead of only Manitoba, according to most recent federal data from late May (data for that period is unavailable in New Brunswick, while Alberta reported its figures separately).
On Wednesday, Provincial Health Officer Dr. Bonnie Henry said the current stock of COVID-19 vaccines in the province are being prioritized for the roughly 1.2 million eligible vaccinated people who still haven’t received any boosters. “All adults need to get that third dose,” Henry told CBC’s On The Coast. “There’s about 1.2 million people in B.C. who’ve had two doses who have not got that first booster. “I would encourage people to do that now so that we use up this vaccine before it expires, and really focusing the fourth dose, that extra boost, for those people who really need it.”
… people may not be thinking of the second booster — or fourth dose — right now because it’s summer, masking has been lifted and there’s a general vibe that COVID-19 is over. But … most health-care workers continue to see new cases of the virus and they are anticipating another wave this fall, when people move back indoors.
Currently only certain priority groups are eligible for the second booster in Ontario. … the government has not yet recommended second boosters except for certain priority groups. ….
CBC News contacted Ontario’s Ministry of Health’s and asked what the timeline is for health-care workers to be able to access their second booster of the vaccine. The ministry’s media office responded with the list of people who are currently eligible to receive a second booster and did not offer a timeline.
Ontario gives the vaccine to people 60 and older, which is already different than recommendations from NACI. The Health Canada guidance for second booster doses, updated in April, suggests people aged 80 and older should get the second booster and provinces and territories “may also consider” giving it to people 70 and older.
At the end of June, advisers to the U.S. Food and Drug Administration recommended that the next wave in COVID-19 booster shots should include a component that targets Omicron to combat the more recently circulating subvariants. I linked to Katherine Wu’s writing in the Atlantic, including her article June 28, 2022 about the US FDA position on new vaccine and more boosters, above.
FDA scientists at the meeting suggested they preferred vaccines that will target the BA.4 and BA.5 Omicron subvariants, which are currently dominant, rather than the BA.1 Omicron variant that led to a massive surge in infections last winter. The fast-spreading BA.4 and BA.5 sub-variants of Omicron are estimated to make up a combined 52 per cent of the coronavirus cases in the United States as of June 25, the U.S. Centers for Disease Control and Prevention (CDC) said on Tuesday. The two sublineages accounted for more than one-third of U.S. cases for the week of June 18.
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Dr. Isaac Bogoch, an infectious diseases specialist at Toronto General Hospital, told CBC News in an interview broadcast Tuesday that BA.5 represents “probably about 20 per cent of all COVID right now in Canada.” Health Canada tracking as of June 24 had tracked BA.5 in 15 per cent of all COVID-19 infections in the country, with eight per cent of cases characteristic of BA.4.
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Pfizer, Moderna and Novavax presented data at the U.S. meeting. All three companies have been testing versions of their vaccines updated to combat the BA.1 Omicron variant. Moderna said it would be ready with a “couple of hundred million” of bivalent, or double-targeted, vaccines designed to combat BA.1 by September. It would be late October or early November if it needs to design a vaccine targeting the newer subvariants, the company said. Pfizer said that it and partner BioNTech already has a significant amount of BA.1 vaccine ready and is preparing to produce a large amount of vaccine targeting BA.4 and BA.5. It said either could be ready for an early October rollout. Both Moderna and Pfizer have said that their respective BA.1-inclusive vaccines generated a better immune response against Omicron than their current shots, which were designed for the original virus that emerged from China. They have said their new vaccines also appear to work against BA.4 and BA.5, but that protection is not as strong as against BA.1.
The Canadian National Advisory Committee on Immunization (NACI) then announced:
People at high risk of severe disease from COVID-19 infection should be offered a booster shot this fall, regardless of how many boosters they’ve previously received … That group includes everyone age 65 and older, NACI’s updated guidance said. Everyone else — age 12 to 64 — “may be offered” the additional doses in the fall, NACI said.
NACI said it will provide recommendations on the type of booster to be given when evidence about multivalent vaccines — which prime the body’s defences against multiple variants, including Omicron and its subvariants — becomes available.
… recommended that booster shots happen in the fall because, as with other respiratory viruses, “incidence of COVID-19 may increase in the later fall and winter seasons,” and new variants of concern could emerge.
The BC Minister of Health in the CBC provincial news July 4, 2022:
The subtitle of the article “10% of health-care staff were sick for at least a day last week”.
The provincial health-care system is getting ready for a fall wave and looking at a federal advisory body’s recommendations that booster doses be made widely available, Dix said speaking at a news conference Monday. Meanwhile, the B.C. COVID-19 Modelling Group, made up of interdisciplinary experts who work independently from the government, warns that a wave of COVID-19 driven by the more infectious and immune-evasive BA.5 sub-variant of Omicron is emerging.
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Public Health Officer Dr. Bonnie Henry said two weeks ago that those hoping for a fourth dose would still have to wait until they are eligible. They are currently only available for people aged 70 and older, Indigenous people over 55, and people in long-term care — six months after their last booster.
Dix also said the province wouldn’t rule out bringing back masks in indoor spaces come the fall and encouraged people to get vaccinated.
The subtitle stated a fact about the effects of relaxing all NPIs: people are acting as if there is no risk of getting seriously ill.
In Ontario, July 6, 2022:
Ontario has likely entered a new wave of COVID-19 driven by the Omicron BA.5 subvariant, the province’s science advisory table said Wednesday, citing exponential growth in most public health units. The COVID-19 Science Advisory Table points to several key indicators that it says signal the beginning of a wave, little more than a month after the end of most public health measures, including mask mandates. For the first time since May, test positivity is above 10 per cent, the group of experts said in a series of tweets Wednesday. Wastewater signals are rising across the province overall and within most regions, it added. Around 80 per cent of public health units are seeing exponential growth in cases, though the group says the actual reproduction number is hard to nail down since the province moved to limit PCR testing.
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Indications of a new wave in Ontario come as several G10 countries have already seen a jump in cases driven by Omicron subvariants, including France, the U.K., Italy, Belgium and Switzerland, among others.”We may be a couple weeks behind in this rise,” the advisory group said.
The group says current evidence does not suggest BA.5 is more severe than strains that drove previous waves or that it will lead to the level of hospitalizations seen at earlier points in the pandemic. “However, any surge comes at a time when hospitals are already dealing with staff shortages and record wait times — this impacts all of us,” the advisory table said. “And if BA.5 spreads widely, we may see a rise in deaths among higher risk groups such as the elderly as was observed during the previous waves.”
With lockdowns lifted and travel opening up, some First Nations in northwestern Ontario are seeing a surge in COVID-19 cases, just as the province’s seventh wave takes hold. There are 514 active cases in the region, a big jump from 124 reported just two weeks ago, said Dr. Lloyd Douglas, public health physician with the Sioux Lookout First Nations Health Authority. The spike in cases comes as public health officials in Ontario announced the province has officially entered its seventh wave, driven this time by the Omicron BA.5 subvariant. “Sadly yes, we’re in another wave,” Dr. Kieran Moore, the province’s chief medical officer, told CBC News on Wednesday after Ontario’s COVID-19 science advisory table pointed to exponential growth in most public health units. Douglas said a number of factors are at work that would explain the rise in remote communities in northwestern Ontario. “The regional chiefs rescinded the regional lockdown several weeks ago,” he said. “Travel is now reopened, and we have members of the community, rightfully so, travelling, getting their business done and coming back to the community. “Unfortunately, individuals would have gotten COVID and then be coming back,” Douglas said, adding that post-travel screening and quarantine policies are still in effect. Still, Douglas said, the case numbers are rising due to variants and waning immunity from vaccines.
“Even though the fourth dose has been available for community members for quite some time, the actual fourth-dose coverage is not where we would like it to be in comparison to … the second-dose coverage,” he said. “So there are multiple factors that have led to the uptake in some of our communities, and we expected to see a little bit of a surge after the communities would have opened up a bit.”
In Ontario, July 7, 2022, direct discussion in the media of the Omicron BA.5 variant:
A highly transmissible variant of the coronavirus is spreading through Canada, driving another wave of infections, even among those who have recently recovered from COVID-19. The Omicron subvariant BA.5, and to a lesser extent, BA.4, is largely behind the latest wave — the seventh of the pandemic and the third since the arrival of Omicron. Both have shown an ability to evade the protection offered by previous infection. “The BA.5 subvariant has mutated to the extent that your body is not recognizing it and people are getting reinfected,” said Dr. Fahad Razak, an internist at St. Michael’s Hospital in Toronto and the scientific director of Ontario’s COVID-19 Science Advisory Table. “So you’re seeing this additional surge start in Ontario, and now it’s started in other parts of Canada as well. “The good news is that data emerging from countries where BA.4 and BA.5 have already taken hold, such as South Africa, suggest they are not more severe than previous Omicron subvariants or more likely to lead to hospitalizations.
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This week, officials in Ontario, Quebec and British Columbia acknowledged that their provinces had entered into another COVID-19 wave.
… Hospitalizations are also climbing week over week in British Columbia, as well as in Ontario, where about 60 per cent of confirmed COVID-19 cases are the result of BA.5. None of the provinces said public health restrictions were forthcoming, at least not during the summer.
In BC in the CBC BC news report of the provincial weekly BCCDC report July 7. 2022:
B.C.’s health minister confirmed the province is entering its third wave of the Omicron COVID-19 variant as hospitalizations jumped 35 per cent in the last week. A day after Ontario announced its third wave, Adrian Dix said cases in British Columbia are also trending upwards, though not as significantly as hospitalizations.”We’re not seeing a major increase in critical care in the most severe outcomes for people who are in hospital and are positive for COVID-19,” said Dix in an interview with Early Edition host Stephen Quinn.
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Dix did not hint towards any new public health measures being implemented to stem the new wave of Omicron being driven by the BA.5 subvariant, and said British Columbia continues to focus on immunization as its best defence against COVID-19, reiterating that vaccines continue to provide strong protection by making hospitalization five times less likely and death seven times less likely. “Those others who’ve been invited have been invited to get your fourth dose. Get your fourth dose,” said Dix.
On Friday July 8, 2022 the BC Health Minister held a press conference to announce that vaccination with 2nd boosters (4th shots) would be available more broadly, including to persons over 60 years of age. (A change from people age 70 and older, Indigenous people over 55, and people in long-term care — six months after their last booster). It will be weeks before the necessary Orders in Council are enacted, workers hired, venues booked, and the vaccination infrastructure is re-established. The government is concentrating on vaccinating young children in August 2022 with newest approved early childhood vaccines.
The government dusted off the vaccination online appointment system and began blasting out messages July 20, 2022 that booster vaccinations would be scheduled “in the fall”. The announcement of boosters became an announcement of boosters before winter.
Quebec
… provincial data shows a waning interest in all COVID-19 boosters over the past few months. According to Quebec’s Health Ministry, only 56 per cent of the total eligible population has received a third shot — or their first booster dose. That number has remained unchanged for a month. Only 19 per cent of the total eligible population has received a fourth dose — the vast majority of whom are aged 60 and over.
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The chair of behavioural medicine at the Université du Québec à Montréal says the provincial government’s failure to be transparent and manage people’s expectations is one of them.
“[The government] said, ‘oh, you know, you’re going to need two doses and that is the definition of fully vaccinated,” said Kim Lavoie of the Health Ministry’s messaging at the start of the pandemic.
While the government has gone on to urge people — not unreasonably, according to Lavoie — to get more doses, she says this has led to confusion and mistrust over the benefits they provide.
“I think that’s what we’re suffering from — from an impression that the government doesn’t know what they’re talking about because they keep making promises and changing the contract.”
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Dr. Matthew Oughton, an infectious disease specialist at Montreal’s Jewish General Hospital, says this slow uptake of booster shots is being seen across Canada.
He expects this is due in part to people waiting to get Moderna’s new bivalent vaccine, which was recently authorized for use in the U.K. It is specifically designed to protect against the highly contagious Omicron variant of COVID-19 and is currently awaiting approval in Canada. It’s unknown when it would be available.
“I actually expect to see a big jump in demand once the bivalent boosters are actually available,” he said, noting their stronger protection against the strain of virus that’s currently circulating in the country.
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Lavoie says now that millions of Quebecers have already gotten COVID-19 — some twice — people’s willingness to get another dose partly depends on their risk perception.
“As risk perception goes down, the willingness to make the sacrifice necessary to get a vaccine goes down as well,” she said.
The expert in behavioural medicine says the Quebec government therefore needs to do a better job of communicating what the added value of getting a booster dose is in a clear and accessible way. …
The virus has survived. At present the prevalent Omicron variants do not cause terrible symptoms for most people, but it hospitalizes and kills some. It evolves faster than pharmacology and medical treatment. There are stories in the news that
Public health authorities and political decision makers in Canada appear to be content that the virus has been “defeated”, school and the econmony restarted, and that public money should be saved.
The USA and Canada
By the spring of 2021, most individuals believed that their risk was low, and resented the restraints on their choices and activities. In the spring of 2022 politicians and public health officials in the USA took the position that Omicron is a minor flu and that the pandemic is over. American politicians believed that the public wants to be told the pandemic is over. Canadian politicians agreed, but have been as vague about it as they can be. Many people were tired of sifting conflicting advice. They were ready to travel, dine out, shop and socialize and enjoy their choices as consumers. People who were sure, for whatever reasons, that they had low risk were not willing to continue with NPIs. People are travelling to express their unhappiness with the way public health measures affected their lives by spending on travel and leisure. There was compassion fade among adults of working age for the risks of the elderly and vulnerable individuals.
Libertarians, Populists, Anti-vax, Democracy
In February 2022, the news media in Canada reported the trucker convoy’s occupation of Ottawa and other populist protests against the measures that had been imposed by governments as conditions of work and travel – the requirements to prove vaccination, and wear a mask. The Canadian governments did not persuade all Canadians to accept that vaccination cards (and/or apps) and masks were necessary to protect the public from the risks of infection with the variants of Covid-19 reproducing in the population.
The protesters may have seen themselves as the leaders of popular movement. They might as well have been screaming “I’m as mad as Hell, and I’m not going to take it anymore”. They were driving trucks, blocking roads, blowing airhorns, demanding things and annoying people. The governments (Canadian federal, Ontario, City of Ottawa) dismantled the protests and charged the protest leaders with offenses. A few protest leaders will be punished, eventually, for breaking rules and annoying people.
The media’s interpretation of public disaffection with government, elites and modern life often seels addresses blame, and may involve conspiracies. The journalists who address mass movements are often puzzled by the way people react to the conditions of their lives.
People have been harmed financially by the effects of the pandemic. People were unable to work to earn money to pay rent and pay for food. The effects of the pandemic continue as a wave of price increases causes inflation of currency and erodes assets and means.
Through the pandemic, American libertarians embraced government’s use of goverment power to use public money to invent a vaccine while complaining that governments have not made the right moves to keep the economy growing to generate wealth for people who hold financial assets. A recent instance in an article by an avowed libertarian economist at the libertarian Mercatus Center of George Mason University:
Operation Warp Speed produced a new vaccine for a novel virus in record time but when Operation Warp Speed was disbanded by the Biden administration vaccine research and development slowed from warp speed to impulse power. It’s ridiculous that it is taking longer to develop and deploy tweaks to the mRNA vaccines to deal with new variants than it took to develop the original vaccines from scratch. By the time we get an Omicron-specific vaccine that variant will have disappeared. This is no way to run a civilization.
We should be investing in a universal vaccine for all sarbecoviruses (of which SARS-COV-II is a member) and, as I have long argued (and here) a nasal vaccine. We need not exaggerate, for the vaccinated the dangers are no longer acute but we should be better prepared for future variants and the savings from less sickness alone easily trump the costs. Indeed, the issue isn’t even so much the cost as the need to coordinate regulatory agencies, as OWS did, to speed approvals and reduce bureaucracy.
The public health authorities have supported masking by people who work with the public or in congregate workplaces. Masks are not protecting workers in a retail stores full of unmasked shoppers, and other public places. The pathogen is a highly contagious Covid-19 Omicron variant.
The public health experts recommend booster doses of vaccine to counter the risk of virulent symptoms, but vaccines are not available to most workers, and to persons who are vulnerable but not in the defined categories. In some Canadian provinces fourth boosters are available to persons over 60 – in denialist Manitoba the threshold is 50. In BC, the threshold age effectively remains 70 until the announcement of boosters becomes action.
The current policy of ignoring the pandemic except for promises of a more vaccine, some day, works at the price of sick workers and an increase in the risk of infection of people vulnerable to virulent illness.
The BC Health Minister’s July 8, 2022 was a messaging exercise. The government sat on its booster supply – waiting for the freedom loving anti vaccers to give in and get shots, or waiting for the federal government to pay for new shots. Bivalent shots may be expected. The Moderna shot approved in the UK is said to address Omiron BA1. Bivalent shots have not been approved in the USA or Canada. The currently prevalent lineage is Omicron BA 5. Nothing in government will start until September, at the earliest.
Modern tires allow cyclists to ride pavements, gravel, trails, dirt, mud, and other surfaces. Pneumatic tires, pneumatically inflated with compressed air, were invented and industrially produced before the end of the 19th century. Earlier, solid rubber was used to manufacture bicycle tires. It was better than other material. Getting a bouncy wheel that did not keep bouncing was one puzzle. Making the tire durable enough to survive contact with the road was another. Rubber proved to be elasic enough to bounce and deform and durable enough to roll for hundreds of miles.
The use of rubber for tires for automobiles and truck led to developments in material science and manufacturing, and to sophisiticated suspension systems. Suspension systems need to be damped to prevent the repetition of cycles of bouncing. Large industries rested on the discoveries that natural rubber was elastic, and could be used to manufacture devices that would contain compressed air. The development of pneumatic rubber tires for cars and trucks allowed bicycle manufacturers to acquire material and devise ways to mass produce tires. Tires have inspired the invention of tire materials, wheel rims, valves, pumps, tire levers, tools, patches, and adhesives. The newer tubeless bicycle tires have led to tire sealant, tire plugs, and tubeless repair kits.
Resources
Cyclists are interested in evaluating tires and learning which tires are efficient and economical. Tire manufacturers will happily say that they manufacture a product, and that their product is superior to other competing products. Scientific material that explains how tires work is more scarce.
Bicycle Tires and Tubes by Sheldon Brown and John Allen at Bicycle Technical Information (the Sheldon Brown site) is a well constructed page with links to terms and topics covering materials and construction. It discusses tire sizes and dimensions. BikeGremlin also explains Bicycle tyre sizing and dimension standards and other technical issues.
BTI is not a resource for information about mountain bikes. BTI published Jobst Brandt’s 1998 “A Brief History of the Mountain Bike ” which said: “The first successful high quality fat-tire bicycle was built in Marin County, California by Joe Breeze”. BTI has “suspension” in its glossary, but does not explain mountain bike suspension systems. Internet seach engines can find pages about bicycle suspension systems – for instance the Wikipedia entry Bicycle suspension but search engines do not respond fulsomely to queries about losses of energy operating bicycles on rough and irregular terrain due to vibration. There is a section on vibration in the Wikipedia entry Bicycle and motorcycle dynamics and a Wikipedia entry on vibration.
Current and historical Information on tires, rubber, and manufacturing tires available in Wikipedia, including pertinent articles explaining:
There do not appear to be standards for how to describe the quality of tires. In a rational world, a manufacturer would have goals in developing new tires and test experimental prototypes and production models. Wikipedia has not found that many industries have adopted methods and standards. Wikipedia, as of June 2022, has pages about
Engineer and blogger Tom Anhalt wrote about tires, tube and pressure at the online triathlon magazine Slowtwitch.com, some listed here, and wrote articles on his own Blogspot blog Blather ’bout Bikes:
A bicycle tire is a strip of durable and stretchy materials laid out in a circle, with edges pulled up to shape the tire in a U-shape. Most tires have beads, a structural part that is durable but not stretchy:
Conventional tires used on 99% of all bicycles are “clincher”type … They consist of an outer tire with a U-shaped cross section, and a separate inner tube. The edges of the tire hook over the edges of the rim, and air pressure holds everything in place.
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The “bead” is the edge of the tire. On most tires, the beads consist of hoops of strong steel cable. The beads hold the tire onto the rim, and are, in a sense, the “backbones” of a tire. While most beads are steel, some tires use Kevlar ® cord instead.
Wire beads are less common than they were in the 1980s. Modern bicycle tire manufacturers use synthetic compounds to manufacture tire beads. Synthetic aromatic polyamids (Aramid) are popular. The rim of a clincher wheel is machined to turn inward to hold the bead in a “bead” hook. Clincher tires use an inner tube, which is airtight and inflated. The butyl rubber inner tube is the ordinary tube; latex tubes for clincher tires are available.
Tubeless tires are clincher tires without inner tubes. They have to be airtight to be inflated without inner tubes. The wheel rim is sealed with a airtight rim tape. The valve is sealed to the rim (and not to inner tube, passed through and opening. A tubeless ready tire is a clincher tire with an inner tube. A tubeless ready wheel rim may have tubeless rim tape, but a tubeless ready system has an inflatable inner tube – the valve is attached to the tube. Tires have been securely clinched to the wheel and sealed airtight by matching the bead with a bead hook structure or bead channel in the wheel rim.
Tubeless tires need liquid sealant in the tire to seal the tire to the rim. The liquid sealant is also supposed to block small leaks and punctures, as well as sealing the bead. A rider can carry tools to plug a small puncture and reinflate it if the sealant has remained in the tire and still functions. As of 2022, manufacturers of wheel rims are building and promoting rims without bead hooks for tubeless tires. There are cost savings in manufacturing wheel rims, and time and cost savings in changing tires, at the risk of tires coming off the rim.
A “tubular” tire, not to be confused with a clincher, also uses an inner tube. Tubular tires are explained at BTI. Tubulars are uncommon and mainly found on racing bikes.
Casing, Sidewalls & Tread
The body of the tire, technically called the carcass, commonly referred to as the casing, is made of “threads”, coated with plastic and rubber compounds:
Cloth fabric is woven between the two beads to form the body or “carcass” of the tire. This is the heart of the tire, the part that determines its shape. The vast majority of tires use nylon cord, though some use other polyamides. … The fabric threads don’t interweave with crossing threads as with normal cloth, but are arranged in layers or “plies” of parallel threads. Each layer runs perpendicular to the next layer(s).
Some tires use thick thread, some use thin thread for the fabric. With thin thread, there are more threads per inch (“TPI”) and this number is often considered an important indication of tire performance. The higher the TPI number, the thinner and more flexible the tire fabric is. Thin-wall (high TPI) tires tend to be lighter and have lower rolling resistance, but they’re more easily damaged by road hazards.
Bicycle tires have the threads of the fabric running diagonally, (“bias”) from bead to bead. Modern car tires have the main threads running straight over from one bead to the other, known as “radial” construction. Radial tires will also have a “belt” of plies running all the way around the circumference of the tire, crossing the radial plies.
In automobile and truck tires, the threads are called cords and may be made of metal. The term cords is also used to refer to bicycle tire threads. Few modern bicycle tire threads are not made of natural plant fibers (e.g. flax, hemp, cotton). Most are filaments of petroleum synthetic (i.e. plastic), often nylon, spun into threads. The threads are not woven into a cloth or fabric. Thread count is a (vague) measure of the texture of woven fabrics – particularly cotton bed sheets. Thread count is not generally a selling point for modern bicycle tires, except that high thread count was used by some manufacturers to mean that that a casing is strong and “supple”.
The threads cross each other in a grid, and are coated in an elastomer – a plastic compound. Some machines produce ribbons of the specified width; some machines produce sheets that are cut to ribbons of the required width. The ribbons are folded over the beads and welded. The threads reach from bead to bead, on the bias (diagonally). Layers of rubber or synthetic rubber compound are applied to the ribbon to form the sidewalls and the tread. The tires are pressed into moulds, shaped, and laminated. In some tires groups of threads (belts), are laid down with the bands crossing each other.
The tread is the part of the tire that contacts the road:
… This area usually has thicker rubber than the “sidewalls” of the tire, mainly for wear resistance. Most tires have some sort of 3-dimensional pattern molded into the tread, which may or may not enhance traction.
Manufacturers mix different additives with the rubber to achieve desired traction/wear characteristics. Generally, a softer formulation will give better traction, but at the expense of more rapid wear. Rubber is normally a sort of tan color, but most tires are black. This is the result of adding carbon black to the mix. Carbon black considerably improves the durability and traction of the rubber in the tread area.
A tread pattern of grooves in a thicker tread is common for automobiles. It was common for bicycle tires through the greater part of the 20th century, except for some special purpose tires. Tread patterns on bicycles do not displace water. Hydroplaning on a bicycle on concrete or asphalt is not a risk . BTI addressed this in a general article and in a 1997 article by Jobst Brandt, “Tires with Smooth Tread. A writer at CyclingTips addressed treads in 2014 in Rubber side down: the function of road tyre tread patterns:
A road tyre is already very effective at displacing the water thanks to its round profile so Jobst Brandt has argued that a patterned tread is unnecessary. A broader survey of current thinking amongst tyre manufacturers supports this view, though some see room for marginal gains through a tread-pattern design.
Slicks or near slicks have become a popular choices for “road” bikes. Some favour a file tread pattern (thin shallow closely spaced ribs at an angle to the path of travel; like the cutting edge of a file – the tool). Jan Heine, the editor of Bicycle Quarterly, and principal of René Herse Cycles addressed this:
… we are examining myths in cycling – things that we (and most others) used to believe, but which we have found to be not true. Today, let’s look at tire tread: Tread patterns matter – they can make a difference – even on the road. “Bicycles don’t hydroplane,” declared some experts many years ago. “Hence, tire tread patterns don’t matter on the road.” The first part is true – even wide bicycle tires are too narrow to lose traction due to hydroplaning – but tire tread doesn’t only serve to evacuate water from the tire/road interface.
In fact, the tread of bicycle tires has other purposes. I once cycled on the polished stone that surrounded a college library, and I was surprised by the lack of grip: I crashed. Even though I was unhurt, I learned the hard way that the coefficient of friction between our tires and the rocks that make up the road surface isn’t very high. Yet we don’t crash on roads made from the same rocks, but in the form of rougher aggregate in pavement. What happens is that tire and road interlock to create grip.
If our grip came only from pure friction, the size of the contact patch wouldn’t matter. Physics tells us that if you double a tire’s width, it will be pushed into the road surface with half as much force – the two cancel each other. Yet race cars run ultra-wide tires because they provide more grip. What is going on?
Tires interlock with the road surface. Imagine each little surface irregularity like a spike that pushes into the tire. The wider the tire, the more surface irregularities it touches; hence it has more grip. A softer tire also has more grip because the road surfaces pushes deeper into the tire. That is why the tires of race cars use very soft rubber, and why wider bicycle tires at lower pressures offer more grip than narrow ‘racing’ rubber at higher pressures.
There is another way to increase the interlocking between tire and road: provide edges on the tire that ‘hook up’ with the road surface irregularities. Each edge provides a point where a road irregularity can hook up. The more edges you have, the better the tire hooks up.
Contact Patch, Deflection, Tire Drop, Rolling Resistance
The weight of the bicycle rests on the contact patches of the tires, the area where each tire deforms from the circular shape of the tire in cross section to the (flat) shape of the surface as the bike rolls forward.
… the role of air pressure in the tire is to hold the fabric under tension — in all but one place, the contact patch with the road surface.
Air pressure can’t add tension at the contact patch, because the contact patch is flattened against the road. Air pressure can only push directly outward, and so here, it pushes directly downward. The downward force of the air must equal the weight load, and so the area of the contact patch approximately equals the weight load divided by the air pressure. (Edge effects and skewing of the weave of the fabric may result in some difference.) For example, if the air pressure is 50 PSI and the load is 100 pounds, the contact patch will be about two square inches.
The threads of the tire fabric can transmit loads only lengthwise and in tension. How then, do they transfer the load from the contact patch to the rim?
Because the contact patch is flat against the road, the curvature of the sidewalls next to it is increased, decreasing their tension, and the angle at which they approach the contact patch becomes shallower. These effects produce the bulge seen at the bottom of a tire under load and transfer the load from the contact patch to the tire sidewalls. The threads of the fabric are pulling downward less and outward more. The load is similarly transferred from the sidewalls to the rim. The sideways forces at the right and left side of the tire are equal and opposite, and cancel out.
Sheldon Brown, John Allen, Bicycle Technical Information, Bicycle Tires and Tubes (see How a Tire Supports its Load)
The rubber at the contact patch bends and rebounds like a spring. The rubber is under tension. The air everywhere in the tire is under pressure but the the tire bulges at the contact patch. The tension of the tire supports the bike.
Because the contact patch is flat against the road, the curvature of the sidewalls next to it is increased, decreasing their tension, and the angle at which they approach the contact patch becomes shallower. These effects produce the bulge seen at the bottom of a tire under load and transfer the load from the contact patch to the tire sidewalls. The threads of the fabric are pulling downward less and outward more. The load is similarly transferred from the sidewalls to the rim. The sideways forces at the right and left side of the tire are equal and opposite, and cancel out.
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A tire, then, supports its load by reduction of downward pull, very much the same way that spoking of the wheel supports its load. The tension-spoked wheel and the pneumatic tire are two examples of what are called preloaded tensile structures, brilliant, counterintuitive designs working together remarkably to support as much as 100 times their own weight.
The rolling resistance of a tire is an example of elastic hysteresis. The deformity also causes the steering tire to experience pneumatic trail.
Frank Berto (deceased December 2019) was the technical editor of Bicycling magazine, before it became a travel and lifestyle publication. He wrote a book on derailleurs, The Dancing Chain – the 2016 5th edition is still on the market. Frank Berto wrote notable articles on “tire drop” – the change in the height of tire when it bulges under load. Some appeared in Bicycling and other print publication, but were not digitized. He rewrote and updated an article called All About Tire Inflation in 2006. Berto wrote or contributed to an article for Jan Heine’s Bicycles Quarterly published in Issue 19 (V. 5, No. 3, Spring 2007). Steve Vigneau has a pdf copy of “All about Tire Inflation” at his site: https://nuxx.net/files/bicycle/various/Frank_Berto-All_About_Tire_Inflation.pdf. Perhaps other copies and other articles can be located on the Web. Frank Berto explained why road bike tires should be inflated to endure tires stayed on the rim under the forces of cornering, and to avoid “pinching” and deflating an inner tube. For road bikes on pavement, he suggested the pressure should be high enough that tire drop was about 15%. He thought that road riders were overinflating their tires. He thought that mountain bike rides should ride softer, but needed guidance to know the minimum pressure to avoid damage to tires and rims.
Frank Berto largely agreed that road bike tire pressures could be lower than the manufacturers’ marked safety warning. He thought that bike tires need pressure to support the bike and rider and to handle properly. He suggested that the pressure should be enough to keep tire drop around 15% for the bike, rider and load. Tire drop is hard to measure. Like rolling resistance and durability, it is dependent on pressure and the thickness and composition of the tire casing
“Rolling resistance” is the mechanical friction generated as the tire rolls. As a segment of the tire tread rolls into contact with the road, it deforms from its normal curved shape into a flat shape against the road, then back to the curve as the tire rolls onward. The deformation of the rubber in this process is what causes the friction. A bias-ply tire has some additional friction because of the “Chinese finger puzzle” effect of the bias plies. The edges of the contact patch scrub against the road as a segment of the tread becomes shorter and wider where it flattens out, then longer and narrower as it becomes round again.
Manufacturers and consumers used wider tires for some bikes and some kinds of riding for a long time. Mountain bikes had and have wider tires. Gravel bikes have wider tires. Cyclo-cross bikes have wider tires than road bikes. Wider tires hold larger volumes of air at lower pressure than narrower tires:
Tire width and pressure are inextricably linked. It is a serious mistake to consider one independently of the other. Generally, wider tires call for lower pressures, narrower tires call for higher pressures.
Consider, for example, a tire one inch across, at a pressure of 100 PSI (pounds per square inch). Air is pushing down against the bottom half of the tyre cross-section with a force of 100 pounds per inch of length. Each sidewall of the tire bears half that load, and so each inch of length of tire sidewall will be under a tension of 50 pounds. Now let’s consider a tire twice as wide, two inches across, at the same 100 PSI. Each inch of sidewall will be under a tension of 100 pounds. So, a wider a tire would ride harder, and need stronger fabric, if inflated to the same pressure,
The part of the tire that is actually touching the ground at any moment is called the “contact patch.” Generally, the area of the contact patch will be directly proportional to the weight load on the tire, and inversely proportional to the inflation pressure. For instance, if the rear tire of a bike is supporting a load of 100 pounds, and the tire is inflated to 100 PSI (pounds per square inch) the contact area of the tire will be roughly one square inch. If the pressure is reduced to 50 PSI, the tire will squish out until the contact patch has become 2 square inches (or until the rim bottoms out against the tire.)
A common debate among cyclists centers on the issue of whether a wider tire has more or less rolling resistance at the same pressure. The constant pressure is proposed because it appears more scientific to eliminate this as a variable, but this is not realistic in practice. The short answer to this question is that, yes, a wider tire of similar construction will have lower rolling resistance than a narrower one at the same pressure. This fact is, however, of no practical value. If you are comparing two tires of similar construction, with the same load, and the same pressure, either the wider tire is overinflated, or the narrower tire is underinflated!
A tire is supposed to deflect a bit under load. This deflection [is] the whole purpose of pneumatic tires. When you sit on your bike, your tires should visibly bulge out at least a bit under your weight. If they don’t, they’re overinflated.
Stiffness can come from thicker casing and rubber. Tire designers can make tires “supple” by making them with thinner casings and thinner rubber layers on the sidewalls and treads. A supple tire stetches and rebounds rapidly with little loss of energy. It rolls with little rolling resistance, and suspends the bike.
Supple tires have drawbacks:
There are four ways to reduce [rolling resistance], each subject to trade-offs:
[1.] The thinner and softer the rubber/fabric of the tire are, the more flexible they become. The trade-off with this is that the thinner the tire gets, the more fragile it is, and the sooner it will wear out.
If the casing and tread are thin, the tire is fragile. The entire contact line of a supple slick tire is exposed to contact with and penetration by small sharp debris. The tread and sidewalls can be gashed by impacts with sharp or pointed edges including broken glass, metal objects etc. on paved roads., and rocks, thorns on gravel and trails.
A patterned tread of hard rubber provided reasonable protection against punctures from small debris, although a pattern leaves an area of the tread with less rubber. The industry addesses puncture resistance with thicker or stronger tire casings and with protection belts. See Cycling Weekly’s Best puncture-proof tyres for cycling 2022.
Knobs & Cleats
Bike, wheel and tire manufacturers designed mountain bikes and gravel bikes with wider tires than road (and cyclo-cross) tires. Tires, with raised tread features – i.e, knobs, ridges or cleats were and are common on mountain bikes. Hybrid mountain bike tires are wider than “traditional” narrow road bike tires but narrower than mountain bike tires. Hybrid mountain bike tires, commuter bike tires and utility bike tires tend to have flat, patterned treads. Generally, gravel tires have knobs.
According to Jan Heine of René Herse Cycles, knobs and other tread patterns do not increase traction on loose aggregate surface materials (gravel). The tires ride on the aggregate material on the top.. The top aggregates slide or tumble on the lower loose material. Knobs do not increase grip on such a surface. Knobs can grip irregular firm surfaces and surfaces covered by thin layers of loose materials.
Some knobby tires can “squirm”:
Knobby treads actually give worse traction on hard surfaces! This is because the knobs can bend under side loads, while a smooth tread cannot. The bending of knobs can cause discontinuities in handling: the tire grips OK for mild cornering, but as cornering force exceeds some critical value, the knobs start to bend and the traction suddenly goes to Hell in a handbasket.
It depends on the size and shape of the knobs, the tread material, and the way the tire deforms and contacts the road. The tire streches and deforms around around knobs when the knobs are under the contact patch.
Thick knobs are less vulnerable to puncture than the thinner parts of the tread when the knobs are in the contact patch. The risk of puncture depends on the shape and size of the debris, the angle of impact, speed, and weight. I can’t find any discussion of the role of knobs in protecting the tire from puncture by small debris.
The knobby mountain bike tires made in the 1980s and ’90s were noisy. Tires with knobby tread were also generally thicker and stiffer. Knobby treaded tires were slower because the tires were stiff and slow. I switched from knobby tires to a patterned tread tires on my Giant hardtail mountain bike, and rode patterned tread tires on my hybrids and my old road bike for years. I was quieter and I thought I was faster. I don’t really know.
Manufacturers have modified tread patterns with knobs and cleats to reduce noise. Modern raised tread patterns are more likely to hum rather than buzz or roar, but can still be noisy.
Valves, Chucks, Gauges
The Schader valve used on automobile tires was used on bicycles in North America. Presta valves were once found mainly on the narrow tires and tubes of road bikes. Presta valves have become common on gravel bikes. mountain bikes and hybrid bikes. Bicycle Technical Information lists Schrader, Presta and Dunlop and illustrates these valves. Wikipedia’s valve stem entry has a 4th type.
A valve stem is a self-contained valve. Cyclists refer to the exterior shell, which is often threaded, as the stem. Some small bike pumps can be attached to the stem. Most pumps attach to the stem with a hose fiting on the pump hose called a chuck.
The Schrader valve allowed cyclists to use air pumps at automobile service stations. The pumps had chucks to fit on Schrader valves, and worked on Presta valves if the user had an adapter. These pumps were useful for cyclists if a service station was near (before service stations began to put coin meters on air pumps) if the user could limit or control the volume and pressure. Some industrial pumps could blow out a bike tire, delivering large volumes at high pressure.
In the 1950s and 60s young cyclists learned to test pressure by grasping the wheel rim and pressing the tread to see if the tire would deform under that pressure. It was not a measurement and it depended on strength and effort. Modern riders have access to analog and digital gauges to test pressure, cycling computers to record speed, location and elevation and power meters.
Pressure – Warnings, Manufacturer Recommendations
Many riders expect the manufacturer to specificy an optimal recommended operating pressure. The value stamped or marked by the manufacturer on the sidewall is not the an optimal value or the optimal value:
Most tires have a “maximum” pressure, or a recommended pressure range marked on the side of the tire. These pressure ratings are established by the tire manufacturers after consultation with the legal and marketing departments. The lawyers want the number kept conservatively low, in case the tire gets mounted on a defective or otherwise loose-fitting rim. They commonly shoot for half of the real blow-off pressure. The marketing department wants the number high, because many tire purchasers make the (unreliable) assumption that the higher the pressure rating, the better the quality of the tire. Newbies often take these arbitrary ratings as if they had some scientific basis. While you’ll rarely get in trouble with this rote approach, you will usually not be getting the best possible performance. … Optimal pressure for any given tire will depend on the load it is being asked to support. Thus, a heavier rider needs a higher pressure than a lighter rider, for identical tires.
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Rough surfaces generally call for a reduction in pressure to improve ride comfort and traction, but there is a risk of pinch flats if you go too far. Even at the lower appropriate pressure, wider tires, because they also are deeper, are more immune to pinch flats.
Testing of tires for automobiles and aircraft (landing gear) for safety was established by governments, regulatory agencies and regulatory bodies. The performance of materials and components in the various situations became a testing point, and testing would have been necessary to sell those products.
Bicycles have been athletic, recreational and entertainment products, and a means of transportation, and even toys. Tire testing, unless required by consumer protection law or the rules of competition, was unusual. The test data for bicycle tires, if any, may be found in the papers of the inventors and manufacturers.
Josh Poertner, the principal of Silca Velo suggested (to Tom Anhalt in an interview (link below), that manufacturers of bicyle tires had no data about tire operation or performance because they were not testing, and that no one knew how to test bicycle tire performance until the early decades of the 21st century. Poertner said that manufacturers relied on their own reputations and industry practice when they made claims that tires were “fast”, efficient, grippy, puncture-resistant, comfortable etc. In a few of the earliest Silca Velo podcasts Josh Poertner discussed tires and inteviewed engineers who had started bicycle tire performance testing:
Cyclists started to demand, unsuccessfully, that when manufacturers claim that competive road casing tires are efficient or fast, they should disclose data. Manufacturers can feasibly test protypes and production samples on testing devices that put pressure on tires as tires are rotated against rollers and drums. Manufacturers prefer to rely on brand reputation and price to persuade riders that a tire is fast, light or high quality.
It is not likely that manufacturers will ever voluntarily disclose research on materials and products under development.
Consumer-led testing
For several decades, from the 1960s, riders, mechanics, bike shops and tire manufacturers shared a common belief and maintained that road bike tires should be narrow and inflated to high pressures. Several sectors of the cycling industry were vested in narrow tires by the 1990s. Road bike frame and fork designs accomodated narrow tires. Wheel manufacturers manufactured wheel rims for narrow tires. Tire manufacturers made narrow tires and tubes.
Cycling magazines seldom pay journalists to test products or challenge the practices of manufacturers who pay magazines to advertise products and publicize cycling. There was some industry reseach on rolling resistance in bicycle tires, but the methods and results are obscure. In an article on the triathlon site Slowtwitch.com:
I’ve heard, though I haven’t seen, reports of rolling resistance studies Continental performed that included an analysis of tire width. … it seems intuitive to me, that there is not much if any measurable difference in the rolling resistance of a 20mm tire versus a 24mm tire, all other things equal. Thinner tires require more attention, though, in that they’re more susceptible to increased rolling resistance if they’re not inflated to a sufficient pressure.
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After you’ve satisfied yourself (or if you’re willing to take my word for it) that a 23mm or 24mm tire will roll as efficiently as a 9mm or 20mm tire, you can move to the next two issues, which are aerodynamics and resistance to flats.
Cycling computers and tire pressure gauges allow riders to check their real speed, tire pressure and other parameters. This allowed riders to compare tires and tire pressures.
Independent researchers including Robert Chung, Al Morrison, Tom Anhalt and Jan Heine started research into road bike tires at or after the end of the 20th century. They recorded data with gauges, cycling computers and power meters available to them. They communicated with each other, sometimes, on Usenet or in other internet services, or by telephone.
Tom Anhalt’s equations to convert Crr (Coefficient of rolling resistance) on rollers to flat surface were written in 2006 (published in 2013 on his blog Blather ’bout Bikes) Tire Crr testing on Rollers – The Math. His charts comparing narrow triathlon road racing tires were published in 2013 on his blog Blather ’bout Bikes, Tire Crr Testing on Rollers – The Chart … and a “how to”. Tom Anhalt’s 2009 article on inner tubes formulated the theory of the breakpoint, at which increasing tire pressure increases rolling resistance:
When thinking about tire pressure and what is “fast”, it helps to think of it in terms of a “resistance to forward motion” rather than just thinking about the rolling resistance of the tire itself. As we’ve seen above, increasing pressure inside the tire decreases the rolling resistance of the tire itself, and this fact has been observed in tests of rolling resistance vs. tire pressure on smooth rollers. With increasing pressure, the rolling resistance drops at a decreasing rate until at very high pressures it’s basically a flat line. So, does that mean that increasing pressure in a tire lowers the rolling resistance of the tire on a rougher surface as well? The answer is: “Yes…but..” The rolling resistance of the tire continues to decrease with increasing pressure on rough surfaces as well, BUT at some point the increasing pressure stiffens the “air spring” so much that the increase in transmitted energy loss overwhelms the decreasing rolling resistance of the tire, with the result being that the actual ” resistance to forward motion” starts increasing. The net result is that above a certain pressure (what I like to call the “breakpoint pressure”) higher inflation pressures make a rider slower for a given power input to the pedals. Adjacent is a simplified schematic representation of this effect. Very little data is commonly available that shows this effect. Mainly out of curiosity about whether or not this effect was measurable, and to what the magnitude of the effect was, this author undertook an experiment “on the road” armed with a PowerTap power meter and a method for determining the Crr (coefficient of rolling resistance – actually, in this case the “resistance to forward motion” proportional to velocity) illustrated here.
Tom Anhalt, Slowtwitch.com. September 21, 2009, What’s in a Tube
Robert Chung developed a power equation that considered Cda (drag area) as well as Crr. He wrote a paper “estimating CdA with a power meter” which has been distributed on the internet. Tom Anhalt discussed the March 2012 version of the paper in his Blather ’bout Bikes post August 4, 2013 “Aero Field Testing using the “Chung Method” – How sensitive can it be?“.
Lower pressure was an innovation when applied to road bicycle tires. Some professional road racing teams or their consultants began to experiment. Some experimenters tried to protect their data and insights to maintain advantages for racing teams, consultants, and tire manufacturers. Academics publish. Manufacturers and consultants hoard trade secrets.
Josh Poertner, before acquiring the Italian Silca Velo brand, had worked on wheels and tires as a manager in Zipp’s Speed Weaponry division, advising professional road racing teams. He was familiar with the literature, and was involved in testing. Josh Poertner/Silca Velo started to podcast or make videos in 2019. Josh Poertner sometimes suggests that the modern engineering of Anhalt has superceded the views of Frank Berto. Anhalt relied on some of Berto’s work in a post on gravel tires February 16, 2020 and his graphs on rolling resistance and pressure. The reasoning and the math is complicated. It seems that Anhalt did not overthrow Berto’s work.
Bicycle Quarterly
Bicycle Quarterly (“BQ”), is a printed publication founded by Jan Heine, the principal of Compass Cycling and René Herse Cycle of Seattle, Washington, USA. BQ was first published in 2002 as a publication about “vintage” bikes. Jan Heine favours drop bar bikes without mechanical/hyrdraulic suspensions: road bikes, endurance road bikes, and “all-road” bikes. His favoured off-road forms of riding include cyclo-cross. He rode Unbound Gravel in Kansas in 2022 on a vintage design René Herse 12 speed (2 x 6) all-road bike. He reviews bikes built by custom builders – frequently bikes built with steel frames. BQ has discussed the uses of bicycles on gravel roads, and self-supported distance riding (randonneuring). René Herse Cycles has a YouTube channel. Some of the videos are about rides in the Cascades and other parts of the US Northwest. Some illustrate bike design, handling, and maintenance:
Most of Jan Heine’s books were independently published by Bicycle Quarterly Publications and sold by René Herse Cycles, and by Amazon:
The Competition Bicycle (2008, reprinted 2012),
The Golden Age of Handbuilt Bicycles: Craftsmanship, Elegance, and Function (2009),
René Herse: The Bikes • The Builder • The Riders (2012),
The All-Road Bike Revolution (2020).
Several of Jan Heine’s books explore history and document the quality of 20th century bicycles. The 2020 book is a short manual for purchasers and riders, and discusses features of modern bikes. Jan Heine frequently observes that modern bikes originated in bicycle designs in the early and middle parts of the 20th century. He respects innovation, but has raised questions about innovations that fail to improve the owner/rider’s experience. He points out that a steel bike from a home builder or small manufacturer can be a better bike, and less expensive than most bikes produced by modern factories.
BQ discussed tire pressure, tire testing and tire design many times. Jan Heine and other riders and writers associated with BQ began testing and writing about rolling resistance and tire tests in BQ issue 17 (aka Volume 5, No. 1, Autumn 2006). Heine respects Frank Berto’s efforts to measure tire drop – he relied on it in developing the René Herse online pressure calculator tool, which became active in the spring of 2022, and cites Berto in journal entries such as “Tire Pressure Take Home” (March 2016).
BQ writers criticized the lack of testing by tire manufacturers, and the use of machines that tested tires on steel rollers or drums. They preferred to test tires by comparing performance on the same surface, without pedalling, by letting bikes roll down measured distances, downhill under low wind conditions – the “roll-down” test. It is a low-tech process that requires time, and measurements of distance, time, and speed. Jan Heine designed tires, manufactured (according to some sources by Panaracer) for Compass and René Herse in Japan, and brought the tires to market. He can be seen as :
a fan of vintage bikes and
promoting his brand of supple tires, and
questioning some of the practices of bike and tire manufacturers.
Jan Heine maintains that hard narrow tires cause the bike to vibrate, even on smooth pavement, which riders perceive as an indication the bike is fast. He summarizes his reseach as supporting the view that an overinflated (hard) tire transmits vibration which slows a rider down – a hard tire is not an effective shock absorber. Jan Heine expressed his views to the readers of the Adventure Cyclist magazine of the Adventure Cycling Association in March 2009 in the article “PSI Rx“. The article discussed the way tires lose energy the rider put out to get the bike rolling forward:
Suspension losses – a bike that vibrates and bounces from one bump to the next is lifted up time and again. Lifting the bike requires energy. Part of this energy is absorbed inthe rider’s body and, on a touring bike, by the luggage. The rest is returned as the bike rolls off the bump. When you accidentally ride into the rumble stripsthat separate many U.S. highways from the shoulder … you also slow down immediately as energy is absorbed in your body. By smoothing out the bumps, pneumatic tires save energy.
Deformation losses – the downside of a soft and squishy tire is the deformation of the tire as the wheel rotates. Most of the energy necessary to bend the tire casing is returned as it springs back into shape at the rear of the contact patch, but some of it is lost to friction within the tire and is no longer available to drive the bicycle forward.
For the best performance and comfort, you need a tire that is neither too hard nor too soft. Instead of inflating your tires to the maximum pressure, run them at the optimal pressure, where they deflect enough to keep the bike from vibrating too much yet are not so soft that they slow down due to excessive deformation losses.
Tire drop measures how much the tire deflects under the load of rider and luggage (Figure 1). For example, if your tire is 30 mm tall without a load and 27 mm tall once you sit on the bike, your tire drop is 3 mm or 10 percent.
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Properly inflated, wider tires provide much more comfort. When you hit a bump and your tire drop increases from 15 to 18 percent, the 23-mm tire will give you only 0.69 mm suspension, whereas the 37-mm tire deflects 1.11 mm. The added suspension of the wider tire makes it faster and more comfortable on rough roads.
But aren’t narrower tires faster? Not really. The key to a fast tire is a supple thin casing that requires less energy to deform than a sturdier thicker casing. For a variety of reasons, many wide tires use heavy-duty casings, which are indeed slow. Wide tires with high-performance casings can be very fast. In Bicycle Quarterly’s tests, the five fastest tires ranged in width from 24 to 37mm. … thin supple casing is faster because it absorbs less energy as it deforms.Thus, it will deform more for a given bump, making it more comfortable than a sturdier tire with a thicker casing (for the same tire width and pressure). The downside of a thin supple casing is reduced resistance to punctures.
Jan Heine’s point is that a supple tire deforms and recovers faster, and absorbs road vibration that a stiff tire will not. Jan Heine acknowledges that the thin supple casing has disadvantages and risks, including reduced resistance to punctures. In the printed BQ articles about his attempts in 2021 to record the Fastest Known Time on the Oregon Outback route, he discusses the risks of gashing supple tires on sharp rocks on gravel surfaces.
Jan Heine and Josh Poertner were guests on CyclingTips Weekly Podcast Episode 9, August 21, 2016 “Rethinking road bike tire sizes and pressures“. Elden Nelson, the (former) blogger at Fat Cyclist was the podcast host. (Elden Nelson and Michal Hottner co-host a podcast about the Leadville Colorado mountain bike race, and the Silca Velo Marginal Gains podcast. He stopped blogging in 2022). James Huang, a CyclingTips technical writer, was a guest or co-host. It may be necessary to play the mp3 version – the 2016 episode is not available in the podcast search function in several podcatcher apps. It is over an hour long. Jan Heine and Josh Poertner agreed that lower pressures were faster. The discussion was summarized in an article in/on CyclingTips in 2017 “What is the optimal tyre pressure?“
The amount of energy that is wasted due to suspension losses increases significantly as the surface of the road gets rougher. Jan Heine measured huge losses when riding the rumble strips that border some roads while Josh Poertner found that even a small amount of over-inflation (10psi) could produce an obvious penalty.
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Much of the data favours wide (25-28c), supple tyres at lower pressures (60-80psi/4-5.5bar), but every rider should feel free to experiment with tyre size and pressure until they are pleased with the performance of the bike.
They agreed that many riders would be better off with wider, softer and more supple tires, and that the optimal tire pressure is usually below the manufacturer’s safety warning. Each had reasons, and relied on particular data points. Poertner cited “supple” practices of professional road racing teams such as the use of latex inner tubes (as opposed to the more common butyl rubber tubes) and the use of thin casing supple tires in races. Poertner agreed that that overpressure beyond the breakpoint (see Tom Anhalt, above) can produce a penalty. They had some differences, but they did not discuss or debate them. The article in/on CyclingTips is imprecise on some points. As the breakpoint is dependent on weight and sensitive to surface, a rider may have to monitor pressure, use data based calculator programs, and test. Rolling resistance cannot be stated for a tire, without knowing other parameters.
The Consultant’s View
Josh Poertner is an engineer and entrepeneur:
He views reducing tire pressure as a way of reducing rolling resistance as a marginal gain for competitive riders;
He favours the idea that new ideas, methods and products are generally better;
He is aware of the costs and constraints affecting the way tires are made – the cost of material, the costs of machines, transportation, energy and labour;
He is aware of the way engineers in the automobile-related industries have addressed the constraints;
He is responsive to the financial constraints of industry.
Like the Ferengi on Star Trek, manufacturers focused on the acquisition of profit as the highest goal can resist making performance the highest standard – it a customer wants high performance, like a professional cycling team manager, the customer needs lots of money.
By 2016, according to Josh Poertner, several road racing teams were using slightly wider tires, and pumping the tires to pressures determined by their procedures for the weight of the rider and bike, and road conditions. Poertner referried to chip seal and gravel as rough. Poertner says he is impressed by Chung, Anhalt and others who have worked with mathematical formulas and gather data with specific tools. Poertner accepts testing on rollers and rotating drums.
This kind of testing involves some machinery. When testing became feasible enough for riders to tinker and test, it also became more feasible for manufacturers and industry stakeholders to test. Testing on machines can be standardized and scaled – and is less costly for manufacturers:
It is relatively straightforward to measure rolling resistance under controlled conditions. A large rotating drum or a set of rollers can be used to reproducibly identify relatively minor differences in rolling resistance allowing different brands, models and sizes to be compared and ranked to identify the “fastest” tyres. The influence of other variables — including tyre pressure, different inner tube materials, and for tubular tyres, the method of gluing — has also been tested.
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It was Tom Anhalt that first raised the possibility that there was more to rolling resistance than friction alone. By comparing his “lab” data with real-world data, Anhalt noticed an unexpected increase in rolling resistance when high tyre pressures were used on the road. Jan Heine and Josh Poertner subsequently confirmed these observations, ushering in a fresh view on rolling resistance and renewed appreciation for lower tyre pressures.
Poertner says he thinks roll-down testing is very limited. He appears to view Frank Berto’s work as out of date. Poertner is focussed on the marginal gains of improving aerodynamic performance. Poertner’s views are influencing cycling influeners – e.g. Lennard Zinn:
… if there is a question about whether a fatter tire is faster than a skinnier one on a rough road, where the bigger tire should have the advantage, then on a smooth road, the narrower tire will likely come out ahead. And even if there is little or no difference in rolling resistance, the advantage will go to the narrower tire overall, due to its lighter weight and lower aerodynamic drag. Contrary to that René Herse blog you sent me, bigger tires are slower aerodynamically, except when the rim is wider than the tire.
As for the René Herse tire rolling-resistance results … This is the methodology the author (Jan Heine) employed for those René Herse tire tests. I respect the enormous amount of work, time and effort that went into those tests. On the other hand, you can’t accurately quantify a small friction difference between tires, tire widths, or tire pressures when the main thing you’re actually measuring, namely aerodynamic drag, dwarfs those tiny differences.
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I’m still left with the fact that the main thing determining the riders’ speeds was wind resistance, since rolling resistance is so much smaller of an effect. That’s why, if we really wanted to be able to quantify what tire pressure, width, or model was faster than another, we needed to do it in a lab, and it couldn’t be just any lab, as I explain[ed][November 23, 2021, Technical FAQ]
“Unfortunately, the only way we can truly know the tire pressure breakpoint for a particular rider on a particular surface is to conduct virtual elevation testing (Chung Method testing), which is a methodology whereby we can use real-world data sets to back-out rider CdA and Crr to very high degrees of accuracy. Having done hundreds of these tests, what we find is that the ‘fastest tire’ in the field is the same one we find on the smooth or rough drum in the lab, but the breakpoint pressure depends greatly on rider size/weight/body composition, as that is what is ultimately driving the whole spring/mass/damper side of the equation.
“If you wanted to test that with a machine, you’d have to do some sort of shake rig testing (as we do with racecars) to determine the spring/mass/damping relationship at each tire contact patch and then model that into your bump drum to simulate that spring/mass/damper on top of the tire. Again, the fastest tire will still be the fastest tire, but you could then accurately predict breakpoint!
“This is what makes our tire pressure calculator so unique; it is a curve fit of thousands of real-world virtual elevation data points taken with pro athletes over a 6+ year period. No, the challenge with this data set is that the selection of tires used is extremely top tier. So, the breakpoint is likely a bit high for those running less extravagant tires, and secondly, our athletes are the fittest in the world, so the breakpoint is likely higher than for the average consumer, as these data were produced with athletes all having very low body fat percentage and therefore, lower hysteresis than most normal people!
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” … roll-down testing, as you know, is a terrible tool for looking at Crr, and I would go as far as saying that it really just can’t/doesn’t work unless you are trying to parse very good from very bad tires.”
— Josh Poertner, Silca president
” … misinterpretation of smooth drum tests has led to misleading conclusions, and really mostly about pressures. Smooth roller tests on tires of equivalent construction, but varying widths, shows that at equivalent pressures, wider tires test faster on the smooth drums, and, with “appropriate” pressures in each, are basically equivalent. Yes, smooth roller tests, or rough roller tests without damping, don’t properly demonstrate breakpoint pressures. Now that this is understood, it’s also important to remember that below breakpoint pressures, roller testing is a very valuable tool for evaluating tire hysteresis losses.”
Lennard Zinn did not explore or explain Tom Andhalt’s comment on the limitations on drum/roller tests at breakpoint pressure.
Poertner assisted journalists at the Hearst publication Bicycling with an article in the spring 2022 issue (Volume 63, No. 4 at p. 65-66, if one has access to this paywalled magazine. I had access through a public library access licence). A test rider was timed and power output was recorded riding a bike equipped with Pirelli P Zero Race TLR tires in three widths – 26, 28 and 30 mm. Each tire width was at three pressure combinations (F/R psi: 90/95, 70/75, 50/55) over two 2.5 mile courses – a smooth and flat (paved) bike path, and a rolling road with “mostly good quality pavement”. Poertner is cited for explaining Tom Anhalt’s breakpoint math, as saying that wider tires are not necessarily faster, and as a supporting the writer’s interpretation of the test results:
“There is the conventional wisdom that wider tires have lower rolling resistance, and if you took a given tire construction and just scaled it, you would probably find that to be true. But in the real world, because of the way tire makers make their tires, that is not always true. I know this can be hard to hear … but it really just depends.”
….
Its not surprising that a 30 mm tire pumped up to 90/95 was the fastest on … smooth flat road. At [20 mph] rolling resistance is not getting overwhelmed by the aerodynamic penalty of the larger tire.
….
The biggest variable that affects your ideal tire pressure (in terms of speed) will be the surface on which you ride.
Bike and tire manufacturers prefer to test on rollers and drums, and deprecate roll-down tests. there are no standards for the tests or the use of tests in manufacturing and marketing.
In road racing, slightly wider tires and lower pressures have become popular, but the adoption of wider tires in competitive road cycling has been limited. The use of wider tires affects frame design. Bicycle manufacturers are competing to produce lighter and faster bikes. Bike manufacturers are replacing metal with plastic composite. At present, carbon fiber is an expensive single-use plastic. Some bike companies greenwash their use of carbon fiber composite as dematerialization. This uses carbon fuels – the energy costs are significant. The road racing interests have tried to get aerobic gains by reshaping bikes and components and changing cycling apparel.
My Tires
My bike in the last half of 2019, 2020, 2021 and 2022 was a 2019 model Cannondale Topstone with WTB tubeless ready wheels to fit 700c tires on a 23 mm. (inner bead diameter) rim. I ran the wheels and tires as clinchers with normal basic butyl rubber inner tubes. The WTB Nano tires had knobs, shown in the photo below. The main tread shows as dusty grey; the raised knobs are black. The larger 4 sided knobs were about 4 mm. front to back x 5.7 mm. The thin knobs on the center line were 14.4 mm. fron to back x 3.75 mm. across, and spaced 5.1 mm. apart. An image of the tread pattern of knobs, arranged in chevrons pointing in the path of travel, seen from the front, is below. These were fairly small knobs, and pretty typical of the tread pattern of modern tires. They were quiet – nearly silent. WTB marked the range of inflation from minimum 35 psi/2.4 bars/240 K.Pa to maximum 55 psi/3.8 bars/380 K.Pa.
Those tires, at 700c x 40 mm., were slightly too big to allow me to put fenders on that bike.
Tread pattern WTB Nano, seen head on
I replaced the WTB Nanos with 700c x 38 mm Panaracer Gravel King SK tires. The actual diameter of this tire (distance from the widest point between the sidewalls) on the 23 mm. rim was about 41.5 mm. The tires were marked with tubed maximum pressure 75 psi/5.3 bars/ 525 kpa, tubeless max 60 psi/ 4.0 bars/ 400 K.Pa
These had, as shown in the image below, 3 rows of 3.5 mm. x. 3.5 mm. square knobs (2.5 or 3 mm high) on the center of the tread, 9 knobs per square centimeters, in a waffle pattern, and some slightly larger knobs on the shoulder between the centre of the tread line and the sidewalls (SK stands for small knob). The small knobs on the center line have the center line thick tread on the contact patch, and some grip on pavement. The knobs were soft enough to give with side pressure.
Tread pattern, Panaracer GravelKing (SK) tires.
Tom Anhalt included Panaracer GravelKing (SK) at 32 mm. in his post on gravel tires February 16, 2020.
The Panaracer GravelKing (SK) tires rode smoothly, but seemed to me to squirm on worn asphalt, where bitumen showed on the road surface (Wallace Road, in Central Saanich).
From spring 2021 to May 2022, I rode René Herse Barlow Pass 700c x 38 mm. René Herse has this tire in its “all-road”road line of tires. It is basically a road tire. At 38 mm. itis wider than normal for road bikes. The tread pattern is a faint rib to indicate wear, with a fine file tread on the shoulder. René Herse describes/promotes the tires:
For paved roads and smooth gravel, our all-road tread with its fine ribs is the best choice. It combines excellent performance and grip on pavement with surprising traction on loose surfaces – the supple casing allows the tire to grip the surface much better than a stiffer tire.
René Herse advises that the diameter of its Barlow Pass tires should be within .5 mm of 38 mm. The actual diameter of this tire (distance from the widest point between the sidewalls) on the 23 mm. rim was about 41.5 mm with the Extra Light tire and about 42 mm. with the Endurance tire. The height of the inflated tire was about 710 mm. This is little larger than the manufacturer said I could expect. The maximum pressure specified (tubed) is 75 psi/5.2 bars/515 K.Pa.
I picked up some scattered metal debris, which eventually pushed through the tread and casing and caused a number of small punctures of the tube(s). Some caused rapid deflation. Others caused slow leaks. I may have taken some pinch flats. Supple tires are fragile – as many have said.
I installed René Herse Steilacoom 700c x 38 mm. tires in May 2022. This tire was introduced in 2018. It was the first, and at the time the only René Herse (Compass) knobby tire. Tom Anhalt included this tire in his chart of his test and equations of gravel tires in February 2020. René Herse describes this tire as the ultimate cyclocross tire. It has “dual-purpose knobby tread” which René Herse describes this way:
Our dual-purpose knobbies offer supreme traction on dirt, mud and even snow. They are also a great choice for riders who prefer a more aggressive tread on loose surfaces. On pavement, our knobbies will surprise you with their low rolling resistance and excellent cornering grip. They’re the perfect tire for adventures where you don’t know what lies ahead.
The diameter of the tire (distance from the widest point between the sidewalls) was about 38.5 mm., and the height (inclusive of the knobs) is 710 mm. The maximum pressure specified (tubed) is 75 psi/5.2 bars/515 K.Pa. 38 mm. tires can be run at 40 psi, or less, depending on the weight of rider, bike and gear according to online tire calculators including Silca Velo and René Herse .
The knobs are arranged three rows of overlapping alternating knobs (wider models have 5 rows). The knobs overlapping the center line on the 38 mm. tire are 6.8 mm. x. 6.8 mm. Those knobs are engaged steadily, within the contact patch, when the bike is riding straight. The knobs in the outer rows on the shoulders are 7.7 mm. x 7.7 mm. The larger outer knobs closest to the center row line up with every second gap between the knobs on the center line. Some of the outer knobs seem to be in the contact patch and to bear some load in straight line riding. More of the outer knobs will be engaged when the bike is leaned to turn, or rocked.
René Herse has brought out other wider tires with the same knobs. In 2021-22 René Herse has been promoting the tread design by listing the riders who have used René Herse knobby tires in gravel races and endurance events.
These tires work with my fenders. On my first rides on these tires, I thought the tires lived up to claim that dual purpose knobby tiress were as fast as René Herse’s slick 38 mm. road tires. The hummed a bit. They ran smoothly on fresh asphalt pavement, worn pavement, and packed gravel. The knobby tread does not pick up water from a wet pavement. It does pick up bits of gravel and throw them into my fenders, as other tires do.
Pressure Calculators
Generally
Riders can use online calculators to assist in the determination of optimal pressure. These depend on data sets, and several parameters. The calculators are generally in the cloud – on a commercial site. Some require registration. Few remember a user or previous data. All want the user to state/enter weight, wheel diameter, tire width. Getting the weight of rider + bike + load can involve standing on a scale holding the bike, weighing some gear separately, and adding up the weights.
The calculators depend on the rider’s use of a gauge. A rider needs, of course, a pump. Many tire gauges appear to read the nearest bar and the nearest psi. My gauge can read the nearest psi but only reads the nearest .1 bars. Tire gauges, like hoses, have to connect to tire valves. Some air bleeds off. Gauges are vulnerable to wear and tear, and can deliver inconsistent readings.
Some calculators want the use to classify the riding surface. On any given ride, I may encounter a few hundred meters of new pavement, a lot of worn pavement, some chipseal and some gravel. This parameter cannot even be predicted some days. A rider will live with the pressure in the tires, unless the rider want to deflate or pump tires en route.
Silca Velo
The Silca Pro Tire Pressure Calculator is free – it does not charge a fee for registration or use. It no longer asks me to register or log in, but perhaps has tracked me and identified me. It requires 7 parameters – some are drop-down choices. It asks for weight of rider + bike + load, as other calculators do. It asks me to enter, from drop-down menus:
wheel diameter;
tire width to the nearest mm. – actual measured width, not manufacturer’s stated width (this is possible with a caliper);
“Tire type”;
average speed. The 6 options start at Recreational and include “Pro Tour”;
Weight distribution – a front/rear % split:
Time trial or triathlon 50/50;
Road 48/52;
Gravel 47/53;
Mountain bike 46.5/53.5;
Surface condition
Surface condition parameter has 10 choices (as of June 2022) from “Track (Indoor wood)” to “Category 4 Gravel”. There is a visual guide. The difference in optimal pressure between smooth pavement and chipseal can be about .4 bars (nearly 6 psi). I use worn pavement or Cat. 1 gravel (not “poor” pavement) as the closest estimatse of local conditions.
This calculator will state calculated optimal pressures to the nearest psi or .05 bar. (1 bar = 14.5 psi. At two decimal places, the bar number also give the pressure in K.Pa; 1 bar = 100 K.Pa). The optimal value for a recreational speed on poor pavement, bad gravel or a dirt trail, is almost a minimum pressure. It is worth checking pressure almost weekly and making time to pump tires up in case they have lost .2 or .3 bars.
René Herse
The René Herse Tire Pressure calculator does not calculatedifferent pressures for front and rear tires. It requires only two parameters: weight and tire width. It provides two optimal settings a “soft” setting and “hard setting”. It is based on Frank Berto’s tests and his theory that tire drop was the best signal or symptom of optimal pressure.
The soft setting is close to the Silca setting for Cat. 1 gravel. The hard setting is close to the Silca setting for tires of the same width, for worn pavement.
The title of Tim Spector’s 2015 book The Diet Myth refers to one “myth”. The book begans with an Introduction that discusses the author’s midlife health crisis when his blood pressure rose suddenly, and present an overview of his research into the modern diet. The Introduction identifies the problems of deciding “what is good or bad for us in our diets” and several misconceptions about food that impair discussion of food and diet, and sensible decisions by consumers. In his later book Spoon-Fed, he discusses many other misconceptions or myths about food science, appetite, differences between individual metabolism, diet and health.
The Diet Myth‘s first chapter introduces discusses some of the gut microbiota (part of the human microbiome) that process food consumed by humans by breaking it down, releasing nutrients that the human gut absorbs and metabolizes. In reviewing Dr. Spector’s, 2020 book Spoon-Fed, the English writer Bee Wilson said it contains an overview of many medical and scientific studies of genetics, microbiology, biochemistry and food:
The book’s main argument is that to find the best way of eating we need to ignore much of what we are told. … Spoon-Fed is a worthy successor to Spector’s earlier bestselling book, The Diet Myth, which focused on the powerful role that the microbes in our guts play in determining our health. This new book is broader, but he manages to distil a huge amount of research into a clear and practical summary that leaves you with knowledge that will actually help you decide what to add to your next grocery shop.
food science and popular writing has not absorbed the fact of the presence of an active microbiome in the human digestive tract,
the importance of a healthy and diverse gut microbiome,
the overuse of antibiotics and other medical errors that have harmed humans by affecting their microbiome,
medical and cultural practices that have contributed to the increasing incidence of food allergies. The book suggests that food science and popular writing has been inattentive to genetic variations of humans as affecting metabolism and interactions with food and microorganism.
The remaining 18 chapters discuss the topics addressed by the “Food Facts” labels used to disclose information about food: calories, fats, nutrients, and warnings, with reference to genetics and the microbiome.
The science of calories is based on the 1944-1945 Minnesota Starvation Experiment. Calorie-based thinking suggests that diets aimed at reducing weight or “curing” obesity should reduce the intake of calories. This has evolved into a proliferation of diet advice: avoiding all fats (or bad fats), avoiding carbohydrates. eating “paleo”, eating protein, eating “Mediterannean”, not eating cheese or nuts. The food industry dominated by corporate interests, is focussed on reducing foods into packaged commodities, processed to taste good, package well and sell. The food industry reduces food to “ingredients”. People try to make up for “missing” ingredients by taking supplements.
The book discussed the scientific “discovery” of “vitamins” with a brief reference to the illness known as beri-beri, caused by thiamine (vitaman B1) deficiency. One of the principal causes where the food supply is primarily “white” (milled or polished) rice is processing the rice:
Beriberi was known for millennia in Asia, but was not described by a European until the 17th century when Brontius in the Dutch East Indies reported the progressive sensorimotor polyneuropathy. The prevalence of beriberi increased greatly in Asia with a change in the milling process for rice in the late 19th century. In the 1880s, Takaki demonstrated the benefits of dietary modification in sailors, and later instituted dietary reforms in the Japanese Navy, which largely eradicated beriberi from the Japanese Navy by 1887. In 1889 Eijkman in Java serendipitously identified dietary factors as a major contributor to “chicken polyneuritis,” which he took to be an animal model for beriberi; the polyneuritis could be cured or prevented by feeding the chickens either unpolished rice or rice polishings. By 1901, Grijns, while continuing studies of beriberi in Java, suggested a dietary deficiency explanation for beriberi after systematically eliminating deficiencies of known dietary components and excluding a toxic effect.
….
By the 1950s synthetic forms of the vitamin were produced cheaply, allowing both therapeutic administration and prevention with food enrichment.
The use of polished rice was culturally and economically embedded – it was easier to cook and digest, and conserved the fuel needed to cook rice. This problem was not an exclusively pre-modern or Asian problem American and European scientists criticized the use of bleached white wheat flour to bake bread and other cereal products. The public policy response was to require that white flour be “enriched” with nutrients. The book also mentions studies demonstrating that agricultural products harvested in modern times contain less nutrients than the products harvested several decades earlier. The book does not refer to studies about the causes and consequences of this fact. One consequence is that vitamin products are marketed as necessary to supplement foods available to consumers in markets – and that supplements have become a huge industry
The idea of enrichming some processed food is embedded in public health policy, and supplements are embedded in culture. The book touches the issues with criticism of the scientific and industrial idea of “reducing” food to a mixture of ingredients, and with criticism of fad diets. Food science in the 19th century and the 20th century failed to addressed dangerous unknowns, and failed to warn against risky agricultural and food processing practices. Science is now not exploring the known unknowns, and public policy remains uninformed. This area can be developed further – although it was beyond the scope of Dr. Spector’s book.
The Diet Myth
suggests that food science, as discussed in the popular media, has been static,
suggests that individuals might eat more vegetables,
recommends diversity of diet and expressly and implcitly endorsies Michael Pollan’s advice to “Eat food. Not too much. Mostly plants” and much of what Michael Pollan wrote in his books In Defence of Food (2008) and The Omnivore’s Dilemma (2006), and
Pizza is a leavened flatbread, usually leavened with yeast. Like other bread, it is made with salt. A pizza made from scratch at a restaurant or at home can have more salt, processed cheese and processed meats than a person should eat.
Making pizza dough is similiar to making bread. A pizza crust can be made with flour, water, salt and yeast, and a little sugar or olive oil to enrich the dough. The dough will be a dough ball which will ferment (“rise”) and be flattened for baking. A dough ball to make a 10 inch thin crust pizza will be small, and have to be tenacious to stand up to rolling into a thin crust.
A pizza can be baked in a home oven, although no home ovens achieve the temperatures and conditions of the ovens used in restaurants.
Mark Bittman’s pizza dough recipe involves flour, water, salt, instant yeast and olive oil. His recipe uses 2 tsp. (11.4 grams) of salt, 1 cup of water (237 g.) & 3 cups of flour (408 g.) (B% hydration 58%). This recipe calls for 11.4 grams of salt in 650 g. of wet dough. The calculation of sodium per serving is not straightforward. 11.4 g of salt contains 4.56 g. of sodium (= 4,560 mg.) 650 g. of wet dough makes enough crust for 3 or 4 servings. Each serving would have 1,110 to 1,500 mg. of sodium. The RDA is 2,000 mg.
Mark Bittman recommends mixing and kneading in a food processor, which takes about half a minute, with some extra pulses. In a stand mixer, a yeasted dough can be mixed and kneaded in less than 10 minutes. He recommends letting it rise at room temperature, or more slowly in a refrigerator, before dividing, shaping a dough ball, wrapping and freezing. He suggests using a frozen ball within about a month.
Peter Reinhart has dough recipes in his pizza book, American Pie. His recipes use 1¾ cups of water (415 g.) & 5 cups of flour (680 g.) (B% hydration 61%) His recipes call for stand mixer or hand kneading – not in a food processor. He favours cold fermentation in a refrigerator. He says his doughs can be divided, shaped as dough balls, wrapped and frozen for up to 3 months.
Peter Reinhart, in American Pie, has a recipe to make 4 x 10 inch pre-baked crusts that can be kept frozen for 3 months. These are not thin crust pizzas.
Beth Hensperger has pizza dough recipes in The Bread Lover’s Bread Machine Cookbook for doughs for 2 x 12 inch thin crust pizzas, or 1 x 14 inch deep dish pizza. A pizza cannot be baked in a bread machine; bread machines mix and knead dough in a Dough program or cycle. Her basic recipe calls for US All purpose flour which is has less gluten than Bread flour (or Canadian All purpose flour) and makes a less tenacious dough. This is a recipe for a chewy regular or deep crust.
Recipe
Flour (Volume)
Flour (US oz.)
Flour g.
Water (Vol.)
Water g.
B%
Salt g.
Instant yeast g.
Basic
3.5 cups
16.625
471
1.33 cups
315
67%
8.6 (1.5 tsp.)
5.6 (2 tsp.)
A home cook can mix dough, divide it into balls and refrigerate or freeze dough balls for future use. A recipe that uses 3 cups of flour will make enough dough for a large pizza or 2 smaller pizzas, or 4 small or thin pizzas.
Some grocery stores sell pizza dough balls. These are warmed or thawed, shaped, topped and baked at home. The Holy Napoli brand distributed by a firm in Port Coquitlam is available in local stores, occasionally. The dough ball is 300 g., and contains 1.3 g. sodium, 72% of the RDA. Salt is crystallized sodium chloride, not pure sodium. A recipe for 300 g. of wet dough will, normally, require 3.3 g. salt (a little more than half a teaspoon of table salt). The other ingredients are flour, water and yeast. I am not sure how to compare frozen dough to wet dough at room temperature. 300 g. of wet dough is a little less than 200 g. (1.5 cups) of flour and a letter more than 100 g. (less than half a cup) of water. That seems to be a normal ratio of salt to flour, consistent with other dough recipes.
Any of the dough recipes above would have to be adjusted to reduce sodium. for users with hypertension or salt sensitivity, or concerned to limit consumption of sodium. A pre-mixed dough, or course, cannot be adjusted. A pizza made from scatch can be heathier than a frozen, pre-made pizza, or pizza made with pre-mixed dough.
Frozen pizza is a dressed pizza on a partially baked crust. It is kept frozen and is baked in an oven in about 15-20 minutes in a 400-425 degree (F) oven to finish the crust and heat the pizza to serving temperature. Frozen pizzas are easily heated and baked. They are not healthier than other pizzas. A short survey of some 10 inch (25 cm.) frozen pizzas in the freezer cases of local grocery stores follows. For some of these pizzas, the calories, sodium and other food facts label ingredients are stated for a 1/4 pizza serving. The numbers here are for the whole pizza. The processed frozen pizzas are not more salty than some pizza dough recipes, but that is not saying much. I include the % of USDA RDA (which is 2,300 mg.):
Brand
Line
Style
Crust
Topping
Specialty
Mass
Calories
Sodium
Dr. Oetker
Ristorante
Thin Crust
plain
Margherita
330 g.
840
1260 mg., 55% RDA
Dr. Oetker
Ristorante
Thin Crust
plain
Spinach
390 g.
910
1420 mg., 62% RDA
Dr. Oetker
Ristorante
Thin Crust
plain
Vegetable
385 g.
760
1560 mg., 64% RDA
Dr. Oetker
Good Baker Feel-Good
Multigrain Stonebaked
Spinach & Pumpkin Seeds
Vegan
350 g.
720 g.
1340 mg., 58% RDA
Much of the sodium found in the industrially processed frozen pizza is in the dough. On industrially processed frozen pizza, the processed cheese is abundant, and salty. They contain wheat flour unless the product is a gluten free fake pizza. There is soy bean oil, and there are mystery additives. These products are convenient, but not particularly tasty.
Zambri’s, a restaurant in Victoria sells a proprietary “Pantry” line of frozen restaurant dishes, including pizza. The pizzas are not labelled with retail nutrition/food facts labels. The pizza are larger, thicker and heavier than those above – about 580-600 g.
Some stores have Pillsbury pizza dough in a tube. The ingredient lists indicate that the dough has been mixed to bake to some thing like a frozen pizza. The oil is soy oil, and there are mystery additives.
The United States of America was founded as a republic. It does not recognize that members of a hereditary aristocracy have formal legal power to make laws or command other persons, or any personal legal rights and privileges. America has social classes, based on wealth and income. Sociologists recognize 6 classes:
Upper Class or the SuperRich;
Upper Middle Class – affluent or rich – highly-educated, most commonly salaried, professionals and middle management with large work autonomy;
Lower Middle Class – semi-professionals and craftsmen with a roughly average standard of living. Most have some college education and are white-collar;
Working Class – clerical and most blue-collar workers whose work is highly routinized. Standard of living varies depending on number of income earners, but is commonly just adequate;
Working Poor – service, low-rung clerical and some blue-collar workers. High economic insecurity and risk of poverty;
Underclass, lower class or the Poor – limited or no participation in the labor force. Reliant on government transfers.
Some sociologists and political scientists maintain that social and political power is held by individuals who are members of elites. American Populism, as an ideology, asserts the wishes and interests of “common” people against elites. Americans tend to deny that they are elite. Sociologists have not developed a common clear way of referring to elites, as opposed to classes.
Michael Lind is a centrist on the left-right spectrum of American political views. He was a conservative, but broke with American conservatism. He is a critic of the upper and upper middle class elites who administer neo-liberal economics in American business management. He is critical of the globalization of trade. He disagrees with American libertarianism. He has supported the idea of liberal nationalism.
He has published his ideas in his 2020 book The New Class War, and in articles America’s Asymmetric Civil War, published January 5, 2022, and The End of Citizenship, published in March 22, 2022 on the website of the magazine Tablet. One of the central ideas of The New Class War is that labour relations are permanently segmented between elite upper middle class managers and professionals, and lower paid lower middle class and working class workers. Lind relies on split labor market theory. Financially elite upper class and upper middle class shareholders play the elite workers in the middle class(es) off against the working class and the working poor on immigration, trade, social policy, and other issues, and win most political fights in the US system. Lind is critical of the broad acceptance of the neo-liberal economics of the American upper class and upper middle class by the media and by most politicians in American politics, and the obliteration of movements for financial equality by identity politics.
The New Class War was written before Donald Trump and his supporters tried to resist the result of the 2020 election. The Asymmetric Civil War article was written for the anniversary of the riots in Washington DC in January 2021. It repeats and updates the book on some points:
The Democratic coalition is an hourglass, top-heavy and bottom-heavy with a narrow middle. In addition to hoovering up the votes of college-educated Americans, the Democrats are the party of the Big Rich—tech billionaires and CEOs, investment banking houses, and the managerial class that spans large corporate enterprises and aligned prestige federal agencies like the Justice Department and the national security agencies. …
The social base of the Democrats is neither a few liberal billionaires nor the more numerous cohorts of high-school educated minority voters; it is the disproportionately white college-educated professionals and managers. These affluent but not rich overclass households dominate the Democratic Party and largely determine its messaging, not by virtue of campaign contributions or voting numbers, but because they very nearly monopolize the staffing of the institutions that support the party—K-12 schools and universities, city and state and federal bureaucracies, public sector unions, foundations, foundation-funded nonprofit organizations, and the mass media. By osmosis, professional and managerial values and material interests and fads and fashions permeate the Democratic Party and shape its agenda.
While the liberal Big Rich cluster in silver apartments and offices in trophy skyscrapers in the inner core of blue cities, the elites of the outer suburbs and exurbs tend to be made up of the Lesser Rich—millionaire car dealership owners, real estate agents, oil and gas drilling equipment company owners, and hair salon chain owners. This group of proprietors … forms the social base of the Republican Party despite efforts ,… to rebrand the GOP as a working-class party.
….
If hourglass Democrats are dominated by urban managers and professionals linked to the national and global economies, and the diamond Republicans by moderately rich local business elites, then who speaks for the two-thirds of Americans who are working class, who lack college diplomas and must work for wages? The answer is: nobody. At 6% and falling, private sector trade union membership in the United States is lower than it was under Herbert Hoover.
The only time that the working-class majority had any real influence in American politics, as well as in their workplaces, was between the 1940s and the 1980s, when private sector unions were a force that both parties had to reckon with. Private sector unions have been annihilated in the last half-century in the United States because hatred of organized labor is one of only two areas of agreement between socially liberal Democratic Silicon Valley tech entrepreneurs, CEOs who donate millions to Black Lives Matter, and small-town Republican sweatshop owners and overseers who think Social Security and Medicare constitute “socialism.” The other thing that the Democratic Big Rich and the Republican Lesser Rich agree on is the need for more indentured servant “guest workers” from other countries who are bound to the employers that sponsor them, and who are thus more easily manipulated and intimidated than either free American citizen-workers or immigrants with green cards who can quit bad employers.
Lind’s analysis of the differences between woke capital, old Capital, the woke managerial-professional class, the lesser Rich (the lower upper class and the wealthy upper middle class), and the working class does not account for large parts of the middle classes (the American petite bourgeoisie). Others agree that the disputes between American elites are significant but classify the disputes differently. Joel Kotkin, (author of The New Class Conflict 2014 and The Coming of Neo-Feudalism 2022) writing for the British online magazine unHerd in “Do We Need a capitalist civil war“:
… the French economist Thomas Piketty aptly divides our capitalist class into what he calls “the Brahmin Left” and the “merchant Right”. One side, as its caste association assumes, tends to see itself as more spiritually enlightened, as priests of the progressive secular religion. The merchant side, however, is more concerned with market competition (particularly from China), the cost of goods, and the impact of regulatory policies on their core businesses.
Today, the Brahmin Left has its base in large corporations and investors, and has allied itself with the academic and media establishments, financing non-profits and generally supporting increasingly intrusive government. By contrast, the merchant Right draws its natural support from the traditional middle class — skilled workers, high-street businesspeople, and small property owners — who also have become the bulwark of the Trumpian Republican Party.
….
[The] corporate shift to the Left, particularly since the Black Lives Matter protests, has created a backlash within the capitalist class, with many concerned at what they see is the creation of a highly regulated, less competitive and openly politicised economy. Add to this Biden’s own embrace of progressive ideology and it’s hardly surprising that many traditional capitalists now fear for their future.
….
And at first, this corporate class seemed to support the Biden administration’s priorities on immigration, racial “equity”, gender, and climate change. But the government’s incompetent Afghanistan withdrawal, the intensifying border crisis and its own economic programme weakened this capitalist ardour. Most critical has been Biden’s stunning failure to address the roots of rising inflation. While costs of living soared, his supporters claimed everything was either temporary or Vladimir Putin’s fault. But it is clear inflation was rising rapidly before the Ukrainian invasion, and is now considerably higher than key competitors, such as Japan, Germany, France, Canada and China.
….
Amid a contentious climate, who will win this new capitalist civil war? Hopefully neither side, at least not too decisively. As unromantic as it may seem, the middle and working classes rely on political competition between the elites to survive, as it forces them to make concessions … the enemy of mass progress is in the uniformity of elites: when autocracy thrives, and when a small group of people — be they feudal lords, oligarchs or party cadres — control the political field, it is the middle and working classes who suffer.
What Lind wrote about American Democrats applies to the self-styled progressive Canadian political parties, the Liberals, the New Democrats and the Greens. What Lind wrote about American Republicans apples to the Canadian Conservative party – a neoliberal party that wants to lower wages.
This is Part 9 of a series of 9 posts organized as a single work, collectively “endless”. From March-August 2024 I reorganized and revised the long article extensively. There are 8 parts, individually published as posts on this blog. This is the table of contents of the series, the 9th post. This post has been most recently updated August 26, 2024.
The series is organized into sections, numbered for reference, in this series table and in the table pf contents for each post.
Most of his SF writing is YA. His characters explain things or do things that he explains. SF writers notoriously tended, and some still tend to explain scientific premises of the setting or plot. He tends to the explantory on coding, the internet, commerce, protests, and activism. He favours free speech too much to be “Woke“. He appears to not discuss gender identity or some Woke issues. He is progressive or Left on privacy, and opposes corporate or government surveillance and the application of behavioural economics and other “sciences” to influence people follow and be controlled to buy things or be “governed”.
He is a GenX journalist/publisher/entrepreneur/activist, born in Toronto, who has lived in London (UK) and Los Angeles. I read some of what he wrote when he was writing for Boing, Boing. He has written on information tech issues. He has published policy advocacy, technical information and opinions, and some fiction on the Internet. He now (as of early 2022) publishes “an old fashioned link-blog” – an almost daily summary of links with an RSS feed at Pluralistic, cross published as a mailing list newsletter. It include sections:
Name
Content
Daily Links
On some days, links to his podcast Craphound’s news/latest blog. Some times his podcast is a reading of an essay or article published on his partially gated Medium1Medium is a publishing platform site/platform. It has a partial or soft paywall – the site tracks something and puts up a “you have x free articles left” banner. The differences between Medium and Substack affect writers. blog site. On most days, links to sections of a daily published short essay at plurastic.net on issues and ideas, tech and the news.
Hey look at this
Link to third party material, usually with interesting images
Wayback machine
List of links to material published on web on this day, in history, mainly about tech and information
Colophon
Lists with links if any currently writing, currently reading, latest podcast, upcoming appearances, recent appearances, latest book, upcoming books.
On March 8, 2022 he linked to his review of David Graebber and David Wenngrow’s The Dawn of Everything. I had been struggling with this book and had not finished it – it was high demand it with many holds in the library system. He refers to sections that I read, in the first half of the book. It is an interesting book that straddles the division between ideas of human evolution and culture that assume that whatever human beings do is natural and morally good, and whatever human beings do tends to greed backed by power, and morally bad things. David Graebber thought many social, economic and political institutions that have bad consequences for people are not the automatic or natural way of doing things.
On March 17, 2022, Doctorow’s article “Late stage capitalism is weird capitalism” discusses Benjamin Braun’s paper “Asset Manager Capitalism as a Corporate Governance Regime” with asides on a current attempts to reform US legislation on corporate concentration (anti-trust) and US federal central bank policy on wages and inflation.
On March 20, 2022 he reviewed Dark Factory, a YA dieselpunk novel.
On March 22, 2022 he discussed the Electronic Frontier Foundation paper “Ban online Behavioural Advertising” on privacy, data gathering, targetted advertising and surveillance capitalism.
On April 28, 2022 he discussed the dark pattern web ads that deposit cookies, build tracking of users and subsidize the sale of information that identifies web users. He mentioned a hardware ad block device. (Dark Patterns see:
On April 29, 2022 he discussed contextual ads, which trick Web user into opening pages that the large tech companies unilaterally interpret (use) as consent to place cookies, harvest data and receive ads.
On April 30, 2022 he discussed Disney’s excuse to break a contract to pay royalties to Alan Dean Foster for his popular Star Wars novel(s).
Cory Doctorow works hard and almost always says something new and interesting.
This is Part 8 of a series of 9 posts organized as a single work, collectively “endless”. There are 8 parts, individually published as posts on this blog, and a table of contents of the series in the 9th post. The series is organized into sections, numbered for reference, in the series table of contents and in the toc for each post. From March and August 2024 I reorganized and revised the long article extensively. This post has been most recently updated April 23, 2024.
Satisficing
At one time, the problem of what was good enough could be answered with a slogan such as “close enough for government work” or “The Best is the enemy of the good“. The term satifisficing, invented by the economist Herbert Simon, defines a condition believed to be good enough, even if it is not entirely optimal (the best). It is used by project managers, economists, psychologists and even by philosophers.
Henry Ford is reported to have said in 1909 of the Ford Model T: “Any customer can have a car painted any color that he wants so long as it is black.” The Ford Model T, produced from 1908 to 1927 cheap, mass-produced, powered by an internal combusion engine, was the most popular automobile in the world. At first the cheap mass produced automobile was a marvel. Later, automobiles had to be faster, safer, more efficient, more aerodynamic, prettier, and produce less harmful emissions, and became very expensive. Bicycles have become more complex and expensive too.
Bike manufacturers make bikes that are better for some surfaces and conditions, and encourage consumers to buy and use multiple bikes. Whether a bike or a component is the best available for a rider may be unknowable until a rider rides it a lot, and has encountered road conditions and weather. There are imperfect aspects to owning and maintaining a bicycle. The manufacturer’s team made decisions about design features and components. They aimed to make a bike that can be sold profitably to many cyclists. The manufacturer of my Cannondale Topstone gravel bike used a mediocre, KMC chain to make an affordable bike. SRAM PC chains are more expensive, but mediocre too.
Chain Size
Shifting problems can also be caused by the shifters, the derailleurs, the chain, sloppy execution by me, or bad karma. Shifting problems are often blamed on incorrect alignment of the rear derailler pulleys with the cassette cogs.
I looked at my bike at rest and on a repair stand many times, but not at the position of the rear derailleur pulleys when the chain was on the large chain ring and largest rear cog, or the smallest chain ring and the smallest cog. I avoided pedalling in those combinations. Generally if I was going to climb, I would be on the small chain ring. A few times, I would get into the smaller rear cogs on the small chain ring which lead to a rattle or rumble sound. I could not see what was happening as my legs were pumping, I was looking where I was going, and the bike was at speed. I thought the chain, nearing its outer position on the cassette, with the front derailleur in the inboard (small chain ring) position was starting to rub the outer plate of the front derailleur.
The main way of sizing a chain in Sheldon Brown’s Bicycle Technical Info page in the section Chain Length in the article on derailleur adjustment ensures the chain is long enough to run in the largest combination of the diameters of the chain wheel and cassette cogs. That method and the complementary check of chain tension at the other extreme are shown in the Park Tool article Chain Length Sizing and video How to Size a Chain and in the Global Cycling Network’s Dan Lloyd video How to Calculate the Correct Chain Length.
In February 2022 after I had broken the derailleur hanger, and had taken the bike to a mechanic for replacement of the rear derailleur cable. The mechanic had made the adjustments to the cable barrel to match the cogs, and the derailleur positions to the shifter indexing. The bike had a new rear derailleur cable, properly installed and adjusted. I looked at the rear derailleur pulleys in both exteme positions.The derailleur pulleys had some room to go further when the chain was on the large chain ring and largest rear cog, and there was slack in the bottom span of the chain when the chain was on the smallest chain ring and the smallest cog.
The chain was a full link (25.4 mm.) too long. I had sized the new SRAM chain in 2021 against the KMC chain on the bike, which had been new when I bought the bike. The KMC chain was not replaced when I had replaced the original Shimano cassette with a SRAM cassette in the winter of 2019-20.
I sized my new chains in 2022 against the resized SRAM chain – one full link less. I operated the YBN chains with fresh paraffin lubrication. Other problems with the derailleur and cable had been addressed by a mechanic as I said above. The chains shifted without skipping the shift or jumping a cog when I tap a shifter lever.
YBN SLA-110 or YBN SLA-1100
YBN is a brand of YABAN Chain Industrial Co., Ltd., a manufacturer of steel products based in Taiwan founded in 1989. SLA is used to describe chains made with “Special Lubricating Aid”, a coating described as “NI-PTFE blend”.
The Yaban site, in late 2023, discusses the SLA-110 chain. An SLA-110 chain has YBN’s SL+ feature, a laser cutaway section on the inner and outer plate. YBN claimed 8,000 Km life on its SLA-110 11 speed chains, which it describes:
the SLA110 comes standard with laser cutouts and hollow pins to reduce weight; DHA chromium hardening to increase service life (up to 8000 kilometers); and Ni-PTFE treatment to reduce friction and drivetrain noise. Add in chamfered plates for precise shifting
…
Ti-Nitride treatment for durability / … / Flat-step riveting for pin strength exceeding 350kgf / Salt spray test: 500 hours / Arc guide block design for chain stability / Thin plate construction for shift accuracy / Size: 1/2″ X 11/128″ / Pin length: 5.5mm / Total number of links: 116 / For road and off road use
YBN manufactured, at one time, SLA-1110 chains. Molten Speed Wax, the US dealer for YBN had a stock of SLA-1110 chains. It had some with the Black Ti Nitride coating in 2022, and still has some in other colours in late 2023. MSW’s description of the SLA-1100:
Blue collar workhorse chain for training or racing
Compatible with all 11sp drivetrains
Ni-PTFE treatment for reduced friction and noise
DHA chromium hardened pins and rollers for increased longevity
Solid chain plates for maximum strength and stiffness High-quality nickel plating for durability and rust prevention
Dave Rome in the Waxing Endless FAQ at CycingTips 1online but paywalled in 2023, noted that Adam Kerin suggested an immersion waxed YBN SLA chain can be run for 15,000 Km., waxed with Molten Speed Wax (proprietary paraffin blend), if the wax is refreshed at intervals of about 300 Km. The article did/does not distinguish between SLA-110 and SLA-1110 chains.
In February 2022 I ordered a YBN SLA chain with Black Ti-Nitride coating from Molten Speed Wax, and a few pounds of MSW. The production and delivery of Molten Speed Wax in early 2022 was delayed by supply chain and logistic issues. They shipped me a pre-waxed chain, but no wax. I got the chain just after I had replaced a broken rear derailleur hanger, and had the bike serviced (replace the cable to the rear derailleur tuning the setting of the rear derailleur). It was in bubble wrap and a sealed plastic bag. It lacked cutaway sections on the inner and outer plates. It was an SLA-1110.
I did not careful clean the lube/dirt gunk out of the cassette or scrub the chain wheels. I put the new chain on the bike. I ran that chain (the black one) for 557 km, which is far longer than ZFC advised.
I am not sure what happened. I got the chain I ordered. It was better than the chain it replaced. I ordered and installed a second waxed chain. I received an SLA-110. I stopped running the second chain it at 472 km. At that point I installed a new SRAM chain (I called it SRAM ’22 in my notes) lubricated with Silca Synergetic.
When I got some Molten Speed Wax in May 2022 I waxed the two YBN SLA chains. I began to run those SLA chains. I did made efforts to deep clean them with solvent a few times.
My YBN SLA 1100 chain lasted about 5,000 Km before it reached replaceable wear in September 2023. My second YBN SLA-110 chain at just over 5,700 Km, as of March, 2024, has not reached replaceable wear.My decisions to to run those YBN chains as long as I did, and some bad cleaning practices contributed to chain wear.
Lube Directions
Deep cleaning with solvents (see Bike Chains 5) was a niche practice for users who melt paraffin and immersively wax their chains.
I tried to run my new ’21 SRAM chain with a few drip lubes in 2021:
factory grease for a couple of rides. This confirmed to my satifisfaction that factory grease is not a lubricant.
Dupont Multi-Use with Teflon. The chain ran better but was noisy. This was enough to satisfy me that this household lubricant should not be used as chain lube.
Silca Velo’s Super Secret Chain Coating fluid wax product. It was very runny. Most ran off the chain in spite of my applying it the way Silca Velo’s Ask the Expert Video showed. The video made the point that the fluid should be dripped on the chain with the chain cross-chained (large-large combination) and left to penetrate and dry. Silca Velo also recommended or required deep cleaning a new chain with a direction to use the product on an “Ultra Clean” chain. I did not understand that Silca meant “remove factory grease with solvent” when I started to use Silca Super Secret Chain Coating in 2021.
MSpeedwax, Adam Kerin of Zero Friction Cycling and Dave Rome of CyclingTips recommend deep cleaning to remove factory grease from any chain before applying any lubricant. After using the ’21 SRAM chain a for a few thousand Km. in the summer and fall, early in the wet Cascadian winter, I finally deep cleaned the chain, and applied Silca Velo’s wet lube Synergetic. The solvent showed opaque clouds of detergant, wax, water and dissolved grease.
The chain ran silently on the wet lube, but it gathered dirt. Eventually, the chain passed the replacement point, according to the gauge I used. The chain wore in about 5,000 Km. of riding which was better than I expected after the fiasco with Super Secret Chain coating and factory lube.
I bought a waxed YBN SLA chain from Molten Speed Wax in February 2022.. I ordered some bags of MSW wax pellets. In February 2022 MSW was taking orders for shipment of wax at the end of April. The chain arrived in March, and I tried it. After I passed about 300 Km., I topped up the wax on the chain with Silca Super Secret Chain Coating. I did this about 8 AM on a day I rode at noon. It left the chain making some noise. Silca recommends leaving this product for 24 hours to penetrate and dry. I applied more Super Secret Chain Coating on a rest day, and left it for a day. The fluid dries out, and leaves a dry wax. The chain ran better and was good for a few more rides. Super Secret Chain Coating works to top up hot wax applied to a clean chain.
The directions on the Super Secret Chain coating drip bottle and jar, and the promotional material do not tell the whole story. Silca Velo, unlike the larger lube makers, has product directions and resources on the Web.
Derailleur adjustment
A new cable will stretch after time on the bike and shifts. The cables hold the derailleur against springs.
The shifts on a rear derailleur on a single click of an indexed shift are small. Cable stretching can result in a click moving the pulleys too little or too far. The barrel adjuster(s) (I have one adjuster at the derailleur end of the cable to a Shimano 105) make tiny changes in response to a quarter or half turn of the barrel It was necessary to watch YouTube (Park Tool’s 16 minute rear derailleur adjustment) and experiment to learn the skill.
Wet lubes and paraffin don’t mix
Wet lubes adhere to all the metal surfaces they touch including the other drive train componments: chain rings, cassette cogs and rear derailleur jockey wheels. A rider switching to paraffin must clean the drive train to remove wet lube and contaminants adhering to the lube. It is not possible to avoid cleaning the drive train. The wet lube, and dirt adhering to the wet lube adhering to drive train components, will affect the paraffin. It may not happen instantly but it will make the chain squeaky or creaky again
The components must be down to bare metal or plastic. The components don’t have to be washed in solvent to the same standard as the roller chain.
Techno-optimism: Carbon fiber
Carbon fiber composites are used to manufacture bike frames, forks, wheel rims, cranks and handlebars. CyclingTips explained the machinery and processes for mechanics, riders and others not involved with manufacturing
Carbon fibers are a chemically engineered product. Short fibers can be manufactured, spun, weaved and cut into threads, ribbons and sheets. The threads are laid in forms and coated and held together with baked resins and plastics produce long pieces of high modulus (stiff), flexible plastic, known as carbon composite, carbon-fiber-reinforced polymers or carbon-fiber reinforced plastic (“CFRP’). Some industries need CFRP made to high specifications (e.g. aircaft components). The sporting good industries are less rigorous, and the rejection and waste ratio of CFRP material is lower.
There is one company in the world, as of late April 2022, Carbon Fiber Recycling in Tazewell, Tennessee, USA that recycles carbon fiber from composite scrap. CyclingTips NerdAlert podcast covered the company in the April 28, 2022 episode. A composite item has to be shredded, and metals removed. The CFRP is pyrolized. The necessary heat is initially supplied with natural gas, which contains methane. Baking the plastic produces more methane. The methane is collected and use to fuel the process. The carbon fiber is chopped and can be reused. Silca Velo was the first cycling company to use recycled carbon fiber. It uses the fibers to make a tubeless tire sealant. Carbon Fiber Recycling hopes to license its patents, and suggests that recycled carbon fiber can be used to manufacture durable small components.
Manufacturing carbon fibers, baking them into CFRP, and breaking down CFRP burn fossil fuels and produce products of combustion. The bike industries have been using CFRP to replace metal but have not stopped using fossil fuels to make carbon fibers and CFRP.
Manufacturers of bikes, components and lubricants talk around the fact that bikes are manufactured and maintained with industrially manufactured materials and maintained with industrially manufactured petrochemical lubricants, solvents and detergents.
The Way We Eat Now, a 2019 book by British writer Bee Wilson discusses paradoxes of food in the modern world: the success of farmers in growing enough food to feed the world, the inequalities of access to food, and the prevalence of unhealthy eating. Ms. Wilson does not identify herself as a chef, biologist, ecomomist or food scientist. She approaches food as a consumer, cook, parent and journalist.
The book suggests that individuals might spend more time cooking and eat more vegetables, apparently endorsing Michael Pollan’s advice to “Eat food. Not too much. Mostly plants” and much of what Michael Pollan wrote in his books In Defence of Food (2008) and The Omnivore’s Dilemma (2006). The book makes a stronger argument about the problems of modern food.
The prevalance of unhealthy food was discussed in this excerpt or digest from the book:
What we eat now is a greater cause of disease and death in the world than either tobacco or alcohol. In 2015 around 7 million people died from tobacco smoke, and 2.75 million from causes related to alcohol, but 12m deaths could be attributed to “dietary risks” such as diets low in vegetables, nuts and seafood or diets high in processed meats and sugary drinks. This is paradoxical and sad, because good food – good in every sense, from flavour to nutrition – used to be the test by which we judged the quality of life. A good life without good food should be a logical impossibility.
….
Almost every country in the world has experienced radical changes to its patterns of eating over the past five, 10 and 50 years. For a long time, nutritionists have held up the “Mediterranean diet” as a healthy model for people in all countries to follow. But recent reports from the World Health Organisation suggest that even in Spain, Italy and Crete, most children no longer eat anything like a “Mediterranean diet” rich in olive oil and fish and tomatoes. These Mediterranean children, who are, as of 2017, among the most overweight in Europe, now drink sugary colas and eat packaged snack foods and have lost the taste for fish and olive oil. In every continent, there has been a common set of changes from savoury foods to sweet ones, from meals to snacks, dinners cooked at home to meals eaten out, or takeaways.
….
For most people across the world, life is getting better but diets are getting worse. This is the bittersweet dilemma of eating in our times. Unhealthy food, eaten in a hurry, seems to be the price we pay for living in liberated modern societies.
The author appears to agree that Green Revolution succeeded in breeding growing plants that put calories in mouths, but observes that agriculture failed to add to the quality of diet of most humans. She appears to agree with the United Nations’ Committee on World Food Security that food security means that “all people, at all times, have physical, social, and economic access to sufficient, safe, and nutritious food that meets their food preferences and dietary needs for an active and healthy life”, and that the Green Revolution did not provide humans with food security. She does not attempt to explain how the Green Revolution changed the way that food is purchased by food processing companies and sold in markets of the world or discuss the issue in terms of agricultural economics.
In a 2015 article, Ms. Wilson discussed her thoughts on the way food is discussed:
It’s easy to be negative about this: much easier to criticise the overweight two thirds of the country than observe the smaller proportion who are in, well, proportion. “What they should be telling us,” she insists, “is that one third of the population, assuming they are not anorexic, bulimic or compulsive exercisers, have positive eating habits which means that eating well is a pleasurable thing.” We’ve become moralistic about food and size, waging war with words. “It’s not ‘naughty’ or ‘virtuous’. It’s food,” Bee fumes. “Painting chocolate as naughty and salad as virtuous just enforces the dualism in which salad is unpleasant and sweet things, frankly, sound like way more fun.”
Changing the lingo is just one part of the battle; changing attitudes is the objective. A good starting point, Bee suggests, is to remind ourselves that as omnivores, eating has long been a complex thing. “We don’t have an instinct that tells us what to eat,” she says. “We have to educate ourselves. It’s not a moral thing. It’s a skill we learn.” When people say it’s easy to lose weight—move more and eat less—it is not just insensitive, but patronising. “It’s not about intelligence. It’s about education.”
In Scandinavia they’ve tried diet interventions at various ages: using cooking workshops and meal planning, they’ve introduced both young and old to new tastes. Projects carried out in Finland proved that children’s tastebuds can be broadened considerably, and in Sweden even 70-year-olds were taught to like vegetables eventually. “It’s not hopeless at any age.” On the other hand, she reminds me “there are plenty of highly intelligent people who haven’t worked out how to stop when they’re full.”
Ms. Wilson critiicizes sweetened soft drinks – ultra-processed compounds of water, dissolved sweetener, and flavourings. The majority are sweetened with sugar. The brain registers that the liquid quenches thirst, but does not register that the person has consumed enough sugars to provide energy for hours of activity. In the absence of activity, the body converts the glucose to fat. She also says:
The occasional bowl of instant ramen noodles or frosted cereal is no cause for panic. But when ultra-processed foods start to form the bulk of what whole populations eat on any given day, we are in new and disturbing territory for human nutrition. More than half of the calorie intake in the US – 57.9% – now consists of ultra-processed food, and the UK is not far behind, with a diet that is around 50.4% ultra-processed. The fastest growing ingredient in global diets is not sugar, as I’d always presumed, but refined vegetable oils such as soybean oil, which are a common ingredient in many fast and processed foods, and which have added more calories to what we eat over the past 50 years than any other food group, by a wide margin.
Ms. Wilson criticizes fad diets including food promoted by the inventors and supporters of “clean eating”, meal replacement fluids and powders (e.g. Soylent, Huel,). She thinks many energy bars and gels are largely candy snacks (ultra-processed), dressed up as special foods with benefits for some people (e.g. athletes competing in endurance sports). Her view of protein bars is similiar. She discusses the growth of prepared food – whether prepared in haute cuisine restraurants or fast food shops. The food is appealing and plentiful but not nutritious.
She also refers to psychological issues influencing how humans make decisions about buying and consuming food.
Cooking has been socially deprecated. Cooking skills and home economics are not part of the education of children. Nutritious foods are hard to identify, inconvenient, or not available in grocery stores. At the same time ultra processed food is cheap, convenient, strongly flavoured and available anywhere in the world. The book supports the campaigns to regulate the marketing and sale of soft drinks (e.g. the campaigns discussed in the writing of Marion Nestle). In part, this reinforces comments of Michael Moss, the author of Salt Sugar, Fat (2013) about modern food, poor public health policy and advice on diet, the biases and failures of so-called food science in America, calories and obesity.
Another of Ms. Wilson’s criticisms of the food supply and processing industries is that they buy and sell ony a few varietals of several fruits and vegetables, usually based on durability, size and availability in bulk rather than nutrition or taste. The Cavendish banana is ubiquitous, often used to sweeten ultra-processed grain “breakfast”cereals. It is not a nutritious fruit. Some vegetables – e.g. most winter squashes (or all squashes) – are water in a plant fibre shell, and are not palatable. She discusses the efforts of Dan Barber to breed a better tasting squash, which have been covered in articles including Tom Philpott’s Squash Is a Mediocre Vegetable. It Doesn’t Have to Be That Way in Mother Jones in 2018.
In part, Ms. Wilson describes the the world food markets as a giant mess that cannot be solved without political action affecting farmers, processers and consumers:
A smart and effective food policy would seek to create an environment in which a love of healthy food was easier to adopt, and it would also reduce the barriers to people actually buying and eating that food. None of this looks easy at present, but nor is such change impossible. If the transformations we are living through now teach us anything, it is that humans are capable of altering almost everything about our eating in a single generation.
The goal of creating an environment of a love of healthy food is vague, and involves changing the role and power of food companies in the markets of the world and altering the present climate of respecting the perceived preference of consumers for fast food which can be harvested, processed and brought to market with the least expense to producers and processers.
Much of this book discusses ideas first discussed in Ms. Wilson’s column in the Daily Telegraph, interviews with other writers, and articles in publications such as the Guardian. Her material at the Guardian is indexed under her profile.
The net result is that above a certain pressure (what I like to call the “breakpoint pressure”) higher inflation pressures make a rider slower for a given power input to the pedals. Adjacent is a simplified schematic representation of this effect. Very little data is commonly available that shows this effect. Mainly out of curiosity about whether or not this effect was measurable, and to what the magnitude of the effect was, this author undertook an experiment “on the road” armed with a PowerTap power meter and a method for determining the Crr (coefficient of rolling resistance – actually, in this case the “resistance to forward motion” proportional to velocity) illustrated here.
