Unicycle cranks come in a wide range of sizes, from 75mm all the way up to 170mm. But how do you know what length is right for you and your riding? This can be a little bit of trial and error to find the length that works for you and you’re riding. There is no right or wrong crank length, but there are length ranges that are more appropriate for different disciplines of riding which we have outlined below.
Firstly, you need to know that cranks are measured from the centre of the pedal hole to the centre of Hub axle hole. Another thing to note is that not all manufactures make their cranks in the same listed length for example Kris holm has a 137mm length, while Nimbus has a 138mm and Impact have 140mm. Most riders wouldn’t be able to tell the difference between these so you can think of them as the same even though they aren’t.
Unicycle.com supply their unicycles with what we would recommend as a good length for the type and intended use of the unicycle you are buying, but that doesn’t mean you shouldn’t change them.
20” Beginner Unicycle would normally use 114-127mm length
Freestyle Unicycle (20” wheel) would have anything from 75mm up to 114mm. The shorter cranks are great for getting up to speed quickly, they make spins easier, but they make starting and stopping much harder.
Trials Unicycle (19”) would have something around 140mm which gives good control and a nice stance for hopping.
Street Unicycles (19”/20”) seem to be best with lengths from 110mm – 125mm, this range offers the best control for street tricks.
Flatland Unicycles (20") quite often have 100mm -114mm
Mountain Unicycles (Muni – Off road) could have anything from 125mm all the way up-to 170mm. There are a lot of things to consider here, the hilliness of the terrain, how technical the riding surface is (smooth or really rocky) and the wheel size. So, for flatter, smoother terrain you can generally go for a shorter length, but then if where you are riding is steep and rocky the longer cranks would offer you more control and the greater leverage to help with climbing and descending. A good length for mixed terrain is around the 140-150mm range, this gives good control on a mixture of terrain.
Road/Distance unicycles (29” - 36”) get supplied with quite a wide range of lengths, anything from 125mm - 150mm. Basically the shorter the crank the faster go. Short cranks (75-100mm) are great for going fast on the flat, but not very good for hills. The longer lengths are great for climbing but do result in a slower general riding speed. Most distance riders use somewhere between 114mm – 140mm.