Originally Posted by
carleton
Why? Because you lose significant mechanical advantage with each 2.5mm shorter crank.
(Brawlo, I know you know this)
Too damn well! At the carnival mentioned above due to the roller derby being between other events, I was rushing to change gears for the track events. I kept the gearing that I had been used to with my regular 175s. The 165s being 6% different really wasn't a lot, but it was enough to take the snap out of accelerations and I suffered badly in the keirin race where I ran a bigger gear. But that was going virtually overnight from 175-165. I honestly believe that after a month or so, you could condition yourself to adjust to the gear.
I began running 165s during 14/15 due to fit issues, however getting a new custom frame that actually fit me for 16/17 I went back to 175s. The biggest reason was due to the 165s being enough for some muscles not to work effectively. 175s saw better recruitment, but I'm not shorty at 6'5"