Crank length

[tjhill]

My missus tells me length isn`t everything but . . . .
Could somebody enlighten me as to the significance of different crank lengths.
I`m running 170 at mo but will a longer 172.5 make any difference.

Cheers

Tel

[Rob]

if ur crank length is shorter, this means the turning circle is smaller, resulting in the crank being able to complete a circle faster if your fast enough. when ur a real top amazing rider, this helps with hill climbing, for everyone else, im sure it wont make much difference, just stick to what youve got used to

[Mike I]

Terry

I was told only last week that, unless you spin like an egg-whisk (when shorter cranks are a good idea), it doesn't make much difference. I have 170s on my commuting bike and 172.5s on the weekend one, and my knees feel fine - for now at least.

Mike

[richv]

The longer the crank the less force (for the same gear) you have to apply to turn it but the greater the distance you have to push it through to complete one revolution.

The ideal crank length is the one which allows your legs to work through their most efficient range (in terms of power application and movement).

However a difference of 2.5cm on crank length is not going to make a huge difference but you may feel better with one than the other.

I have cranks at 175, 177.5 and 180 on different bikes and have no problems changing from bike to bike. I prefer the 180 cranks, but that's probably because they're on my nicest bike.

[Marek]

Rich, I presume you mean 2.5mm rather than CM else you are riding around on Cranks that are probably longer than your height.