Same ratio, different sized rings cogs, which to choose?
Are there any advantages, or disadvantages to running a large (53) vs a smaller (39) chainring given the same overall gear ratio? In other words, what's the difference between say a 53/20 vs. a 39/15 with all other variables being equal? You'd get more chainwrap with the larger ring, but I don't know if that's good, or bad.
Any help is GREATLY appreciated. ThanX!