pacman76

okay... are there any A) physical therapists/physicians out there who bike regualrly or B) mechanics who have run into this issue:

i ride my bike for about 10 hours a day so it's important to me to have things right for my body. turns out one of my legs is slightly shorter (the left). what that means is that when i adjust my seat so it is comforable for my right, my left knee give me troubles, but when i lower it the 3/16 of an inch to accomodate my left knee, my right knee and left hip bothers me. to make matters worse, i have almost no elasticity in the tendons of the ankle on the left side, so that floppy ankle puts extra stress on my knee, so i really need to favor the left comfort. but when i lower my seat to accomodate that left knee, everything else hurts. grrr...

do they make crank arms that is maybe a few millimeters shorter that i can install on the left side so the diameter of the circle i make on the left will be smaller on the lft and bigger on the right, and therefore the bottom of my stroke will be higher up? or is that not the best way to handle this issue? any other ideas? don't tell me to tie blocks to one pedal ... i use cleats anyhow...

white lobster

a) Cleat shims are the usual fix for leg length discrepancies. A good bike fitter can help you with that.

b) What, pray tell, are you doing on your bike for 10 hours per day?

juicemouse

pacman, in addition to the good advice you're likely to get here, I highly recommend the cyclingnews.com "fitness and training" articles that are posted every once in a while. There is a huge depth of information in the archives. There's a guy who contributes named Steve Hogg. I consider him to be the Sheldon Brown of bike fit. I'm pretty sure your questions will be thoroughly answered in one of his archived posts, but if they aren't you can always send in an email. Check it out, starting at the begining (2002):

https://www.cyclingnews.com/fitness/

pacman76

good idea on a)

regarding b)... i'm a messenger.

pacman76

awesome awesome awesome... thanks.

Retro Grouch 

Individual left crankarms, in various lengths, are available through QBP. They're not too expensive. Most any LBS can get them for you. That's what I would try.

pacman76

wow... i just noticed i spelled "asymmetrical" wrong. embarrassing. or should i say "embarassing"?

phidauex

The problem with differently lengthed crank arms is that if one crank is shorter than the other, the shorter crank will be lower at the top, but higher at the bottom, which won't help someone who has one leg longer than the other, which would need that leg to be lower at the bottom AND at the top.

I initially thought 'different crank arm' too, but on reflection I saw that it wouldn't work as desired..

You need to raise the crank on one side for the entire rotation, and the only thing I can think of for that is a pedal or cleat shim. For toe clips and platforms, you could probably make your own shim by screwing a piece of 3/16 aluminum plate to the pedal that needs to be raised, bringing it up 3/16 of an inch all the time.

peace,
sam

peace,
sam

Michel Gagnon

I suggest you read this:
https://billbostoncycles.com/lower_limb_inequality.htm