Crank length and gearing

RichMTB

I'm replacing my old XT cranks with new ones and I've ordered 170mm crank arms

My main thought was to get a little bit more clearance when pedaling as I do get the occasional pedal strike on my Blur LT.

Will the shorter crank arms have any appreciable effect on the gearing. I have some memory of the term "gear inches" and know its related to crank length and gearing, but is 170mm vs 175mm big enough for me to notice any difference?

nicklouse

sheldon has a big article on it.

if you notice anything it will be that pedaling can be a bit harder as you are losing some mechanical advantage.

Pedal strikes are more to do with technique than crank length.

bomberesque

I'd be willing to bet that you won't be able to tell the difference tbh

Ho hum

You are only losing 5mm on your cranks, which is a fall of 2.9%.

So, all other things being equal you will have to have the force on the pedals by 2.9% to generate the same amount of torque at the crank.

Not really noticeable I think.

RichMTB

Sheldon (RIP) says not to worry either.

bannedbiker

nicklouse wrote:

Pedal strikes are more to do with technique than crank length.

+1