Originally Posted by
Ygduf
why would you not go shorter cranks for a climbing bike?
shorter cranks allow for the leg to stay more extended at the top of the stroke, opening the hip angle. you lose short-term torque for a better endurance position. see TT riding and short cranks.
because -- for road positions -- hip angle is not usually a constraint.
also, conventional thinking here is that as cadence decreases torque becomes more important; people typically use longer cranks in scenarios where they want more leverage at low RPM. MTBs are an example of this.