I’m curious to know if anyone else is curious about “gain ratios” or “gear inches.” I found this calculator online a long time ago(I used it for calculating gear inches for my fixed gear road bike to find the right sprocket size). I’m not exactly sure what to put in for the chainring, sprocket, or cassette values since the unicycle typically doesn’t have one. Basically, I want to see how far I’d travel for any combination of wheel size and crank length. This kind of pointless mathematics fascinates me:)

Here is the link to the gear calculator:

This is entirely independent of crank length.

Aah! Glad you noticed that!

There’s a chart floating about on the forums here that is more suited around uni riding, I’ll try and find it :smiley:

beat ya

or maybe not quite :frowning:

You guys are out of date. This chart was made by saskatchewanian, and he updated it recently to include 32" wheels. (Thanks Eric. BTW, you should put your name on it someplace so people know where it came from.)
Anyway, here’s the latest version (for any newcomers reading this).

This is an eye opener! Thanks for posting those charts.

The gain ratio calculator linked to above does have a menu for crank length, 150-190mm.


When i tried short cranks on my 700c when i tried freemounting it really wanted to push the uni out from under me badly. The shorter cranks made it wear me out fast too, but was fun to try.

I wold not recommend cranks that are too short on a larger wheeled uni unless you want a serious leg workout.

the 20 inch uni i used had cranks that were too long on it and got pedal strikes if i turned too sharp, they are perfect length on the 700c no pedal strikes and perfect control. if i had longer ones I would try them out too.

That chart is great but some of the recommendations might be on the aggressive side. “All around road riding” on an ungeared 29er: 95-100mm cranks? For very experienced riders I think, and maybe not even all of them.

You just have to slowly work up to the short cranks on a 36er. It took me a long to time to be strong enough and to get used to the 110mm cranks. Now after riding with the 110s for over a year, I wouldn’t want to go any longer. I have been able to use them on pretty much everything that I have attempted. I’m hoping to attempt Palomar Mountain on Monday, if I have time. 11 miles up to an elevation of 4200. Wish me luck!

Some people do get on with v. short cranks, it depends on their body shape, the area they live in, and, when it comes to dealing with hills, whether or not they have brakes.

Sadly, there’s always been a tendency for some of them to incorrectly assume that because they get on with, say, 110s on a 36er, that everyone can do so, and go on to perpetuate the myth that everyone, with some work, can use short cranks.

The reality of course, is that many v. experienced riders use longer cranks on their big wheel set-ups, many finding, for example, that 150s are the optimal size for them.

When it comes to hills, it is surprising how well you can learn to climb on v. short cranks, however, they are not nearly so good for descending the same hill, especially if the riders knees are not at their best (v. common for older riders), unless you have a brake (which some unicyclists don’t use out of principle).


A very well, thought out response!

I made that chart in response to a thread about “Total Gear Ratio” which I figured should be “Gain Ratio”.

Anyway like I said in the other thread the numbers are accurate for the “nominal” wheel sizes and a slightly rounded off schlumpf gear ratio of 1.5:1 to allow the 36/G24 columns to overlap.

I added the colours to make it easier to compare various setups and the descriptions are a rough guide based on my experience on 20, 26 and 36" wheels at the time with various crank lengths. I still think they are fairly accurate in my experience, but of course everyone will have their own preferences, and not everything will work for everyone. I quite enjoy riding a 29 with a skinny tire and 100mm cranks as a general purpose road uni.

I went away from short cranks for a while but they are growing on me again, probably because I am spending more time on paved surfaces lately.