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My old pedals were worn and had been damaged by corrosion after an incident in storage last winter

Platform or Clipless

Bike pedals have been flat (platform) pedals since safety bicycles began to be made and sold. Many bikes are sold with flat pedals, which riders will replace.

Bikeradar did a large survey or review early in 2021. Outdoor Gear Labs did another. Both identified several clipless cleat systems, along with Shimano’s, as choices. Cleats may be attached to the shoes with three bolts or two:

  • Three bolt cleats are large, thick, and stiff. They fit a retention mechanism on one side of a corresponding pedal. The large 3 hole “delta” cleat has dominated the market for road cleats since the Look Delta design, which Shimano emulated with its SPD-DL pedals. Shimano uses 13.5 mm M5 bolts to secure its SPD-SL 3 hole cleats to the shoes. 3 hole cleats fit fit below the sole , and only fit into one side of pedal. Most of the pedals in the Shimano Dura-Ace, Ultegra and 105 road bike product lines are 3 hole models.
  • Two hole cleats are smaller. Typically two hole cleats, including the popular Shimano SPD, cleats are used with pedals with retention mechanisms on two opposite sides of the pedal. Shimano uses 11.5 mm M5 bolts to secure SPD cleats to shoes. The cleat engagement uses a spring, adjustable by rotating a bolt in the medal. The pedal is marked to confirm the direction to turn the bolt; there is no tension marking or gauge on the pedal, (The SPD system is a mountain bike system and is marketed by Shimano for those uses.)
  • M5 bolts are the standard device to fix or secure cleants to shoes. There are “cleat nut” shoe plates that fit in soles of two bolt shoes. They are tapped for M5 bolts.

Some flat pedals, made and sold for mountain bikes, have small metal pins for grip – these depend on a shoe that will grip the pins and will not shred.

Shimamo SPD

Shimano SPD cleats support several Shimano pedals and are compatible with some OEM pedals. The SPD system has two slightly different cleats. The (black) SM-SH51 is “single direction” release. The direction is a rotation away for the crank, in the plane of the pedal – when the rider’s anke is at a normal angle to the leg, perpedicular as if the rider were walking, The (silver) SM-SH56 is “multi-directional” release which is not compatible with a few Shimano pedals.

I used a pair of Shimano PD-324 clipless pedals on a Giant hardtail mountain bike and on a Trek FX 7.4 mountain bike hybrid. The PD-M324 as originally a Deore line mountain bike “trekking” pedal. Shimano’s mountain bike product lines are complex. Deore was a line of touring components which crossed over when Shimano launched the Deore XT line in 1983. Deore is now the 4th Shimano mountain bike component tier after XTR, Deore XT, and SLX. A pair weighed over 500 g. The PD-M324 and cleat retention on one side, and a platform on the other. It was flat on both sides. I changed to Shimano PD-A530 pedals, which are similiar to the Shimano PD-A600. Both the PD-A530 and PD-A600 are Tiagra series pedals in the 4th tier of the Shimano road series. Pedals are not part of component groupsets, but Shimano identies some components as groups of related components within Shimano’s system of using product lines to market components.

Both pedals support(ed) the Shimano two hole SPD cleats on one side. The SPD is a “step in” system. Riders clip in by locking cleats on the soles of the shoes into a fitting on the pedals. The PD-A530 was lighter than the M324 at 383 grams per pair. The PD-A530 had an SPD fitting on one side and a flat ribbed surface on the opposite side of the pedal. The PD-A530 is “concave” (? convex) on the the side with the cleat fitting. The cleat lock is over spindle. This emulated the action of other cleats – it let the rider concentrate power on the central axis of the pedal at the ends of the crank arms. This required the rider to have the fitting side of the pedal facing up and get the front of the cleat into the centimeter of space ahead of the spindle. The shoe did not otherwise make other contact with peddle. The PD-A600 was a one sided pedal which differed from the PD-A530 this way “recessed SPD shoe compatible allows off the bike walking”. Jan Heine, writing in Bicycling Quarterly (Spring 2021, No. 75, at p. 108), praised the PD-A600 for these features:

  • ” .. excellent bearings
  • ” … support the rider’s feet on the pedal body … feet do not rock as you pedal”.

The PD-A600 was not on the market when I acquired the PD-A530 pedals. The PD-A600 was lighter at 286 grams per pair, and different than the PD-A530. It was no longer on the market in 2021 when I decided to replace the pedals. Shimano had discontinued the PD-A600 and moved the spd cleat into the Ultegra road bike line with the PD-ES600 in 2020. The PS-ES600 has the recessed fitting,and calling this an Ultegra product meant a price increase (to $140 a pair in Canada in the summer of 2021). Jan Heine noted some disadvantages of the PD-ES600:

  • ” … the [back] of the cage has been eliminated … means they are no longer weighted to facilitate clipping in.
  • “At the end of the ride, the cleats are sometimes hard to disengage.

Jan Heine’s comments identify:

  • the benefits of having a pedal as a platform for the foot and having a cleat recessed in the sole of the shoe that lets the shoe contact the pedal.
  • a problem that can occur with a one sided pedals. The rider has little grip on the second side if any, and a rider can lose speed before flipping the pedal and making a connection with the cleat.

Jan Heine thought the Shimano XTR line PD-M9000 mountain bike pedal worked better for his styles of riding (CX and all road, I think) than the Ultegra PD-ES-600. While the XTR is a spindle with engagement mechanisms on opposite side of the spindle – it lacks any platform, Jan Heine thought the XTR was easy to engage and disengage. He noted the that the fronts of the retention mechanisms had a a “depession that guides the cleat. The XTR pedal is considerablly more expensive than other 2 hole cleat mountain bike pedals, including other Shimano MTB pedals, and hard to find in 2021. It is built to a different standard. I wasn’t able to find one to examine. It has shallow concave scallop in the fronts of the retentions. This appears to be done by grinding. The scallop is present in Shimano MTB pedals models in the XTR grade 9000 and 9100, but other Shimano MTB pedals lack this feature.

His comparison asks questions:

  • why not use a small 2 hole cleat on an all road bike or a gravel bike?
  • is a double sided 2 hole system better than a one sided pedal fitting to a 2 hole cleat?


Ourdoor Gear reviewed the HT T1 enduro pedal favourably and identified it as editor’s choice for a clipless system. The HT T1 was available online. It uses a proprietary cleat which does not work with Shimano SPD system cleats. (The HT X type cleats are thicker than SPD cleats, among other things). It uses a large spring which can be set much tighter than the springs in Shimano pedals. This is popular with MTB riders. See:

  3. .

The cleats are multi-directional. Twist your foot in any plane to release.

The spring is thicker and strong than the spring in a Shimano SPD pedal. Some online sources suggest that 50% on the HT indicator is equivalent to the highest tension on a Shimano SPD retention spring. The gauge in the mechanism that indicates how tight the spring is tensioned. The gauges each track the position of a threaded plate that secures the end of the bolt that tensions the spring. The gauge is a series of 8 lines along a slot in which the plate is visible.

The HT cleat retention sytem is identified as “spring binder” by LakeShoes, which offers advice about how the cleat should line up with sole of the shoe. Lake Shoes provides advice on how highly torqued the bolts holding the cleat onto the sole should be set for some pedal systems, but not the torque for the HT T1. HT has the numbers – 5 to 8 newton meters – in the product manual. HT supplied two sets of bolts to hold the cleats to the shoes. Both seem to be M5 bolts. I later threaded them into a thread checker at hardware store to confirm. Both sets were flat headed & countersunk (tapered on the back of the head). They are specialty bolts with have an opening for a 4 mm Allan Key, like cap screws. One set were ≧11.5 mm long, the standard for SPD cleats. The second set were 13 mm long, providing an extra 1.5 mm. of threaded bolt to engage with the tapped “nut plates” in the sole of the shoe. Longer bolts will project through the tapped cleat nut plate, and abrade the insole. The extra length will be required when the rider deploys shims (as shown in the Lake shoes drawings). It is almost necessary to deal thread into the cleat nut plates through the HT X type cleats.


On the return trip from the West Shore, I saw an incident when some 2 of 4 or 5 persons oncoming on road bikes lost control on the E&N in View Royal. They were riding in a group, in single file but slowed down to pass some pedestrians walking side by side, which affected riders coming from both directions and caused a momentary traffic jam. Two riders in the group went into the ditch. Bruises and road rash, and contact with the West coast rain forest underbruch. They went into the ditch on their right and did not cross into my path. I stopped and assisted, stopping and unclipping. I knew one of the riders, who used to work in the same branch of the same Ministry. This kind of incident is a risk on Victoria’s “multi-use” trails which are not set up for fast cycling, for wide vehicles, or for pedestrians who crowd or cross the centre lines of the trails.

I initially set the spring tension at 50% of maximum, which is more tension than I was used to. Within a few Km of starting my first test ride, I stopped and dialed the springs down . The cleats work like a Shimano multi direction SPD cleat but some motions work better.

I had a problem unclipping the left shoe a few Km later where the E&N trail crosses the rail line at the end of Hallowell (west and south of the Admiral’s Walk shopping centre). I was able to unclip, and continued to the Canadian Forces base gate on Admirals Road at the end of Colville. I crossed the tracks at the gate, went up Colville, turned onto Intervale and turned on the E&N from Intervale. I had unclipped and clipped a few more times. I was getting uneasy and began to looking for a place to stop. I thought I could get off on the shoulder of the next crossing street, Hutchinson. I slowed down but could not unclip my left foot. I was able to get some support from the chain link fence which is immediately beside the trail – on the left. I was able to, unclip my right foot for support and mobility, undo my left shoe and get the bike off the trail. I was not able to get at the bolts holding the cleat. I undid the bolt that pre-tensions the retaining spring, release my left shoe, and remove the cleat from the shoe – without losing any more parts. One of the two cleat retaining bolts had worked loose and had disappeared. I was able to put the shoe on and ride home, using the left pedal as a platform pedal. The GPS stopped recording when I stopped. The walk off the trail was too slow to restart recording until I was on the trail and pedalling. The gap shows my move to the wrong side of the trail but is otherwise nearly invisible in my GPS track of the ride. Later, I reassembled the cleat retaining spring; and

  • confirmed, with the thread checker in a hardware store that the bolts are standard pitch M5 bolts;
  • found standard pitch M5 bolts 16 mm long at 2 hardware stores. Both stores had M5 zinc (plated) steel bolts, flatheaded and countersunk, with slot or Phillips heads. Either would work. There are shortages of all sorts of things (the economy has been disrupted by Covid and the other shocks of 2020-21) and having the bolts in hand provides options,Phillips heads have some advantages but come with the risk that the bolt head strips and rounds when torqued. With some enquiry and looking around, I located M5 stainless steel bolts, flatheaded and countersunk, with Phillips heads. Still vulnerable to rounding, but a bit stronger. I cut them down to ≤13 mm with a Dremel tool, and reinstalled the cleat.

The cleat retaining bolts should be fully engaged and torqued to the manufacturer’s specification to avoid the risk of losing a bolt, which will probably lead to being unable to unclip. Jan Heine describes voming to a stop with your foot stuck in the pedal as one of the worst nightmares of any cycist. I agree. I was lucky in not crashing, and in finding the repair parts. I fixed the problem and reinstalled the cleats properly.

This system signals cleat engagment with a firm click that I can feel and hear. The pedal provides a platform for pedalling unclipped. It has 2 pins at the front which allows me pedal and make a second try to find the front of the spring and clip in if I miss on getting the front of the cleat into the front of the spring.


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