Crank length for climbing bike

Triathlon Forum
1

switching my giant tcr (L) out with compact cranks (34/50-12/25) to be used solely for climbing. currently i am running 175 crank length on that bike and on my lemond zurich (57). I am 6’1" (don’t know my inseam length) and have been running 175s on both bikes with no problems.

My question is would I be better off with 172.5 on the climbing bike with the compact as, theoretically, I should be spinning more, requiring quicker leg turnover, or, leave well enough alone and stick with what I am used to. Will I be even able to feel a difference of 2.5 mm in crank length?

2

there was a lot of discussion last week on the form about crank lenght. I have a relatively short inseam to torso and found shorter cranks worked better for me when I stood up to sprint or climb, otherwise it was hardly noticeable. I went from 172.5 to 170

3

My $0.02 that is based on absolutely no hard evidence or quantitative studies other than my own personal experience:

Stick with the same crank length for all of your bikes. Your primary objective should be to develop a consistent, smooth, round pedal stroke regardless of terrain or positioning. Forcing your legs to make adjustments in your pedal stroke as you switch from bike to bike is not going to help in achieving this goal.

4

You don’t know your inseam length? How do you buy trousers?

5

if by trousers you mean pants :), i just try a bunch of pairs on starting with waist size. i’ve found 32x34 means different things for different brands.

6

I use different length cranks on my bikes. I have Rotor Crank 180mm’s on both my TT bikes and 175mm Ultegra cranks on my road bike. I find that the shorter crank allows me to vary my speed more in group rides, yet the 180’s allow me to power consistantly over a set course. I find no problems switching between the 2 types. I ride my road bike about once per week (recover ride) and log lots of miles on TT bikes each week.

7

My $0.02 worth- crank length is way overrated. I’d bet that most people here wouldn’t be able to tell what length they were on (within the normal range of 170mm - 177.5mm) on two otherwise identical bikes. If you’re currently using 175’s and like them- stick with that. It’s as good as anything else.

8

My $0.02 worth- crank length is way overrated. I’d bet that most people here wouldn’t be able to tell what length they were on (within the normal range of 170mm - 177.5mm) on two otherwise identical bikes.
Exactly… check the pubmed (I think it’s called) database…