Hi, As the previous poster stated. More rpm's on the climbs and a little bit extra omnthe upper end (flats) using an 11. I'm tall and weigh 87kg and not exactly young. Have been doing well on the standard 53/39 and 12-25 thus far, but cannot compete with someone weighing 70kg. From a physiology standpoint the lowest in terms of which I could/should allow my weight to drop is about 79kg. Even then I will look emaciated. Find it difficlut to compete with the youger guys on the climbs. In the interim, I have done a bit of calculations ans I'm thinking of keeping the 12-25 and going compact. This is what I've calculated Going compact 50/34 with the same 12-25 will give me a 16.1% increase in rpm's on the same % incline. e.g if you were doing 62 rpm with 53/25, you will do 73 rpm with a 50/25. You will lose 6.1% on the upper end 53/12 vs 50/12, but can easliy be compensated for this by upping my cadence on a flat (for me this would mean upping it by 6 rpm) The 53 x39 and 11-28 would give me an 11.29% gain in the lower gears, but I would then have to compromise on wider gear shifts in the middle. So for me at least I think it is a done deal. Compact it must be
