Originally Posted by
Wilmingtech
Changing the cranks to a smaller size decreases the range of the pedal spin (a smaller circle). It will make a difference in mashing vs spinning. The power output is the same but the muscle group in extreme cases would be different.
Small crank length differences don't change power output, only preferred cadence. And small differences to crank length only change that preferred cadence a small amount. If you were in your smallest gear, you wouldn't have magically found more power with a 2.5mm shorter crank to go from mashing to spinning. If you weren't in your lowest gear, then you really can't complain that you wanted a higher cadence.