Originally Posted by
PeteHski
I currently have 1 road bike and 1 mtb both on 175 and 1 road bike on 172.5. It's what they came with and I can't honestly tell any difference. But my inseam is in the right ballpark for that kind of crank length according to this fitter's data review:-
https://bikedynamics.co.uk/FitGuidecranks.htm
I'm 6'-1", with a 35" inseam. I changed from a 170mm to 175mm crank arms about 40 years ago when I started participating in ultramarathon events. I think the longer arms helped me especially, since I preferred climbing out of the saddle.
I've always heard that any change less than 5mm is probably not worth it or noticeable.
I'm 65 now, and still ride 175mm on both my road and mountain bikes, and even though I had a total hip replacement 10 years ago as a result of a crash, I have no problem turning over the 175 arms.
BTW, I'm not sure I'd put much weight in that article, since I don't believe overall height plays an important factor in correct crank arm length. I think upper AND lower leg lengths might be a very important thing to consider. One thing I've always been curious about is the ratio of upper leg length and lower leg length. If you have a long upper, but short lower (in comparison), that might result in a different saddle height than someone who has a longer lower leg length. That shorter lower will result in a more open hip angle at the top of the stroke, than the cyclist who has longer lowers, yet still be the same at the bottom of the stroke.
Thoughts?