When I was test riding a lot of bikes, I found out early in that process that I was more comfortable with a 170mm crank than a 175mm. However when checking out bikes, I sometimes forgot to check on it, paying more attention to other aspects of the bike.

I remember taking a couple of longer test rides (20-30 minutes) on the bike I eventually chose, the Fuji Absolute 1.0 . On nearly every other bike, the size that fit me best was a 17"-18" frame. On my test ride on the 17", I liked much about the bike, but couldn't get super comfortable on it. Upon getting back to the LBS, they told me that the Fuji 17" was a bit small for its size and that perhaps I should try the 19". So out I went on the 19".

It took about 5 seconds to recognize that it was a better fit. My riding position felt much more natural, my arms & shoulders were more relaxed. It was great except for one thing, on every stroke it felt like I was trying to step over something that was a little bit too high. Instead of a smooth pedaling motion, I felt like I had to stretch to get over the hump at the top of the stroke. This was on each and every stroke.

Initially I thought that perhaps it was the same on the 17" but the other issues had disguised it. So I got back on the 17" and there was no such sensation. So finally I got around to checking the crank length. The 17" had 170mm cranks, the 19" had 175mm.

At the time of purchase the LBS swapped the cranksets for no extra charge, so I took home the 19" w/170 cranks.

There is no way I'd want to frequently ride a bike that had 175 cranks.