Chains, Gears and Pedals

As we reach the end of May, we have only been able to wear shorts 4 times. The temperatures have generally stayed under 10 degrees (Celsius). However, we have been riding steadily. We didn’t ride in the evenings during the week of May 10-14 due to a spring blizzard. I passed on one ride this week to make soup and pudding for Claire, who had just had her wisdom teeth out. But otherwise I have been out nearly as much as Mike whose odometer for the year is at 872 kilometers since March 28. Steve, who rides to work and rides at lunch (but can’t ride most evenings in May and June since he is a responsible dad with three kids playing soccer) is at 921 kilometers.
We rode to the gravel quarry in Bird’s Hill on Sunday May 23, and we had the rare excitement of a steady, strong tailwind on the way home. I was riding my Giant Yukon, and the ride exposed a shortcoming of this bike. I found that I did not have the top end gear combinations to keep up with Mike and Steve. I suspect that Mike and Steve have smaller top rear rings – 11 or 12 teeth. Mike clearly has a bigger front ring.

I counted gear teeth later and determined that the smallest cog or ring on my rear cassette has 14 teeth. The big front ring has 42 teeth. That ratio, applied to a 26 inch wheel is only 78 inches of travel per revolution. Bicycling Magazine’s Guide to Bicycle Maintenance and Repair has a table of travel which assumes a standard mountain bike gearing of 13 teeth on the smallest rear cog and 46 on the largest front cog, yielding 92 inches of travel per revolution in top gear. For road bikes, they assume a front ring of 53 teeth. Applied to a 13 tooth rear cog and a 27 inch wheel, they approximate 110 inches of travel per revolution.
I have been using the Giant more as a hybrid touring bike than as a trail-riding, mountain bike. I use the small rear cogs much more than the big trail rings, and I need different gearing to get a more out of my bike. A 12 tooth rear cog and a 46 tooth front ring would give me 99 inches per revolution, which would be good for downhills, tailwinds, and sprints.
I bought the bike in 1998. It was supposed to have been a 1997 model. It’s time to renew some drivertrain components. While I may only have put on a couple of hundred klicks a year from 1998 to 2002, the last 2 years have been more intense. The chain is stretched by 1/8 inch per foot, which is past the time to replace it, according to Sheldon Brown, a good and knowledgeable source.
It’s time for a new chain, a new rear cassette, and probably at least one of the front rings. I may have to take the wheel into a bike shop to make sure I get the right cassette to fit my freewheel hub. Replacing Shimano cassettes can be simple under some conditions, but I’m not sure what I’m shopping for.
A few weeks ago I bought a pair of Shimano PD-M324 pedals which have a platform on one side, and a binding for a cleat (for Shimano’s clipless SPD system). Shimano markets them as entry-level multi-purpose clipless pedals. At the time I was looking for something to use on my road bike, without committing to cleats and eggbeater pedals. The salesman (at Winnipeg’s Gooch store) said that I would like the big platform on a road bike. He was full of shit on that point, but I liked the idea of a conventional platform on the other side. I thought that would be handy to have a simple platform if I have to jump on the bike in sandles or regular shoes to run an errand. The platform is like the platform on a regular mountain bike pedal, although not quite as aggressive as some metal mountain bike pedals. I thought I would be able to use them on the road bike for a few rides and switch them to the Giant.
This weekend Mike suggested that I move them to my Giant now, since I use that bike for our mixed surface urban/rural touring and I always wear my bike shoes, which now have cleats, for those rides. It was a logical suggestion. I put the M324’s on the Giant this morning and went for a 20 k ride before the rain arrived. It was a good idea. It let me get rid of the crappy plastic pedals that came with the bike. It forced me to learn to use the cleats and bindings.
I had planned for the option of a cleat-based clipless system when I bought the shoes last year, but I had been reluctant to use the cleats, even when I put the pedals on my road bike a few weeks ago. I found that it’s easy to release from the pedals, although I wonder if I could manage to twist both ankles fast to get out of a spill. Locking the cleats is still a little unpredictable after a couple of dozen attempts Sometimes I find it easily, but sometimes I am fumbling for the correct spot. I am increasingly confidant about hooking in, and I have the platform side if I have to start fast.
Once I was riding with my feet centered on the pedal axles, I looked at the adjustment of the bike seat and moved myself forward an inch, for a tighter and more comfortable ride.
It seems to have been the right decision. With the amount of riding I do, it makes sense to have moved into a higher quality pedal that hold my feet consistently in a good position.
My main regret was not shopping more carefully. Mountain Equipment Coop sells the M324 at $72 per pair. Gooch listed them at $120 but offered a 25% markdown. (The retail price for online vendors in the US runs from $39 USD at Jensens to $97). I paid more than I had to.