Originally Posted by
Bill Kapaun
If your knees don't BEND far enough with the longer cranks, you can definitely spin a lot faster with the shorter arms! More than enough to make up the difference, as in my situation!!!!!
Bill, I've recently noticed my knees feeling tired after a ride and on my stairway the day after. I've been using 172.5's on two bikes this year, and finally noticing it's hard to keep up a good spin. I have more force at lower cadences, but find it harder to maintain 85-90 like I was doing last year with 170s. My pedaling keeps dropping down to the 70-75 range. I think you hit on something, thanks!!
I think I'm going to change back to 170 on at least one of them and see what happens regarding cadence and knee pain. I do know last year I rarely had knee discomfort after long rides.
Road Fan