Cleat stackers/Shims
#1
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Cleat stackers/Shims
Hi. Figuring that those of you on this part of the forum have many miles of experience, and your riding health is of paramount importance, I will try this question here too-as I have posted in other places as well, and haven't gotten too much in response, which kinda surprises me.
I have a 17mm difference between right and left legs. My street shoes are all altered to compensate for this. However, getting custom made cycling shoes I have found to be prohibitively expensive. ($1,000 +) So that's not going to happen. Has anyone used shims added to their cleats to compensate for a short leg? Short of using a power meter (which was suggested) is trial and error the only other way to figure out how many shims?
I have a 17mm difference between right and left legs. My street shoes are all altered to compensate for this. However, getting custom made cycling shoes I have found to be prohibitively expensive. ($1,000 +) So that's not going to happen. Has anyone used shims added to their cleats to compensate for a short leg? Short of using a power meter (which was suggested) is trial and error the only other way to figure out how many shims?
#2
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I would think that you'd be better off using two different crank lengths, say a 165mm on the short leg side coupled with a 180mm on the long side. This reduces the leg length discrepancy to 2mm, which can be easily shimmed. Both crank lengths are readily available.
If you were to use only shims, 17mm in shims would be extremely unstable, as most pedals require part of the shoe to rest on the pedal for stability. If you used mtb SPD cleats, you could use a road shoe and get the SPD road adaptor, which would provide an extra non-cleat mating surface to the pedal. If you shimmed out a Look or SPD-SL cleat, you could end up with the sole slightly above the pedal surface.
Also, note the circle described by your foot using different length cranks vs. shims. With different crank lengths, both L and R pedal arcs would be centered on the bottom bracket spindle. With shims, the pedal arc on the short side would be slightly higher than that on the long side. The center of each circle would be different, with the shorter side having a higher center.
Just some things to consider from a non-professional perspective, so take it all with a grain of salt.
Luis
If you were to use only shims, 17mm in shims would be extremely unstable, as most pedals require part of the shoe to rest on the pedal for stability. If you used mtb SPD cleats, you could use a road shoe and get the SPD road adaptor, which would provide an extra non-cleat mating surface to the pedal. If you shimmed out a Look or SPD-SL cleat, you could end up with the sole slightly above the pedal surface.
Also, note the circle described by your foot using different length cranks vs. shims. With different crank lengths, both L and R pedal arcs would be centered on the bottom bracket spindle. With shims, the pedal arc on the short side would be slightly higher than that on the long side. The center of each circle would be different, with the shorter side having a higher center.
Just some things to consider from a non-professional perspective, so take it all with a grain of salt.
Luis
#4
Uber Goober
Do you already have the shoes? If so, it wouldn't be too hard to try it and see.
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#5
Professional Fuss-Budget
I recommend you talk to a fitter who has some experience with that kind of discrepancy.
It's very likely that something else is going on as well, which may influence the proper way to handle it. E.g. your hips or knee could be doing something weird.
So in some circumstances, using a shorter crank or using shims might help, but it could also make the issue worse. You really need someone to look at your pedal stroke and figure out how to alter the bike to compensate for your issues.
It's very likely that something else is going on as well, which may influence the proper way to handle it. E.g. your hips or knee could be doing something weird.
So in some circumstances, using a shorter crank or using shims might help, but it could also make the issue worse. You really need someone to look at your pedal stroke and figure out how to alter the bike to compensate for your issues.
#6
Randomhead
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it really depends on where your discrepancy is in your leg. When I've seen discussions of this, the discrepancy is in either your femur or tibia but not both proportionately. I know I'm not being helpful when I say that one responds to wedges whereas the other doesn't. I don't know that I've ever seen anyone correcting this with crank lengths, but I'm sure some people have tried it
#7
Senior Member
My partner uses custom orthotics that compensate for part of her leg length difference. The remainder is taken up by a shim under her (road) cleat or a shorter crank when using SPDs. Last year she rode 17,000 miles, so it works for her.