I am a crit racer that took up cross this year. Raced in 5-6 races and fared well in the flat ones and not so well in yesterdays hilly race(surprise). After the race I was talking to the guys that are in 1/2(I am tied for 2nd) in the points. They are using 34/27 and 39/34 for their tallest gearing. This seemed huge to me, as I thought I was going tall with a 39/25. But riding some of the "run ups" and even some of the steeper grades, I was chugging along while they were sitting and spinning easily. I lost contact on the second lap after watching them spin away, while I could barely turn the pedals.
So, I use Q-rings on all my bikes and was getting ready to order a 40T Q-ring for my cross bike to run a single front ring. I was contemplating going to a 12/27 cassette to help with the climbing for the next few races. My question is does a 27 give THAT much more than a 25, or should I maybe find a 28 or 29? And off of that, I figure a 28-29 would need a long cage RD, but do you guys run 27's with a short cage RD's okay?
Thanks for any help!