Crank Length

[CycleJunkie]

I have just bought a new groupset and I was asked what crank length I wanted. What is the difference between the various lengths? How will it affect my riding?

 

Get technical, very technical....

 

[Christie]

I saw a study somewhere on the net that found that crank length made no difference to performance. The cranks in the study were varied from extremely short, 140mm, to extremely long, 210mm or something. The test results showed that rider power output stayed the same regardless of crank length.

In general, most people have to choose between 170mm, 172.5mm, or 175mm. Based on the test I mentioned, you can choose any without affecting performance. There are some formulae to calculate crank length based on rider leg length etc, results mostly come down to tall riders getting 175 and short riders getting 170. 

Christie2008-10-30 20:55:22

[CycleJunkie]

Thanks Christie, that has set my mind at rest. I have also read an article or 2, which just left me confused. That is great