Accommodating leg length disparity

I started about 6 weeks ago and recently found this forum. It’s so nice to see people around my age (57)! I have a leg length difference of about an inch almost all below the knee. On my road bike I handle this with spacers under the cleat on my left shoe. It seems like on the unicyle I am going to have to handle it on the pedal. Does anyone have any experience with this?

You are going to end up with a square pedal on one side if you use packing.

I am still learning (several years on) and find that the most comfortable placement of my foot on the pedal is to have it centred with the arch of the foot over the spindle.
However, if I have the saddle too high, I can gain a little extra leg length by placing the ball of the foot on the pedal, and pointing my toe on the bottom of the pedal stroke.
It is more tiring on the ankle, but it saves effort on my legs, and feels like I have more control.

I suggest you try an offset foot position first, with your longer leg using the centre of your foot on the pedal, and your shorter leg using the ball of your foot so you can point your toes to gain some extra travel on the down stroke.

It may work out OK, or it may not.

I just put an extra insole in one shoe.

If your legs have that much of an offset, how about using dual-hole cranks, with one leg on the long hole, and the other on the short? (Different brands have slightly different hole placements, but the holes one mine are 20mm apart – almost an inch.) The mechanical advantage difference would take a bit of getting used to, but it may be workable.
Good luck! :slight_smile:

The bend at the knee at the bottom of the pedal stroke is going to be slightly different between the two legs, but as long as you’re not approaching a completely straight leg at the bottom of the pedal stroke, it’s not going to be an issue…as far as I can understand.

The simple option is to have the seat set at the right height for your shorter leg. Your longer leg will then be slightly too bent at the bottom of the pedal stroke, but many people ride with their seats low anyway fora variety of reasons.

Plan B is asymmetric cranks. Square taper cranks are cheap and readily available and the experiment would not be a huge investment. Say a 150 on one side and 125 on the other as a starting point.

Building up the pedal would probably not be a good idea as it would increase the risk of the pedal rolling under your foot. The point of contact between your foot and the pedal would be further out from the axis of the pedal spindle so there would be more torque on the pedal and a slight error in foot placement or pedal could lead to a UPD, especially on rough ground or a slope.

A built up shoe would avoid that particular problem, but might be difficult to arrange.

I’ve been wondering, sometimes you see those peeps that lost part of their leg and walk with the prosthesis. Now that I really got into riding unicycling, I naturally also sometimes think what situations would make that I can’t ride. Could be anything. Do yous think peeps with a prosthesis can still ride a uni? I think technically it should be possible.

The only problem I got at home is that the doctor’s found that it I don’t make enough seeds to have a child with my wife and she blames it on the unicycles. She doesn’t ride herself so telling her about the thousands of men that do ride, do manage to have children. She will never be convinced and will always push me to mention it at the doctors who then look at me funny and ask if I’m training to work in the circus.

Riding with dual hole cranks for one shorter leg, will me that the shorter leg will have to work harder to make one rotation and I’m not sure what that will do for mounting. Mounting with shorter cranks is harder than with longer cranks, if ur shorter leg is your dominant leg, you might be in for an additional challenge.

Thanks everyone

Wow, thanks for the creative yet practical ideas! I will probably work through all of them!

I’ve tried riding with two different length cranks and when more than a couple mm it felt fairly awkward. Granted my legs are relatively even.

If you rode with a block spacing out your cleat on a bike why wouldn’t you be able to ride a unicycle with a built up sole on your left shoe?

A bit obvious I know, but sometimes the simple solutions are the best ones.

I have asked Witold to reply to this thread, but it failed to let him for some reason. He has done considerable research on this subject. I am hoping he can give us some of his conclusions when things are working again.


Since you mention your leg length difference is almost entirely below the knee, I think the best option is to account for the differences in the shoes - Adding to one and/or subtracting from the other. Messing with crank length might make sense if the leg difference was primarily above the knee.

Witold has had problems logging in to the forum so asked me to post on his behalf:

I learned uni while 67 yo. managing some 500meters in one go…in protective gear.
Being physician and arthopaedic surgeon 1) I knew I have controlled balance MAINLY by the eyesight. 2) that my left leg was 1inch shorter . 1 inch in orthopaedic opinion is considered ‘normal’.
I was keen to improve my performance so I have done various tricks with crank length and thicker sole.
I still use uni for daily training on rollers without any compensation and it is PERFECTLY OK. I am 83yo. now.
In CONCLUSION the advice of Mikeful MAKES SENSE = adjusting the saddle to shorter leg length comfort.

Pedals of different thicknesses?