Originally Posted by
icyclist
Carbon Unit wrote:
"I have a triple and want to move to a compact sometime in 2011. I will have a different cassette on the compact than I would on the triple and this will give me approximately the same gear range....I will probably go with a 12-27."
So you're giving up a little at the low end, a little less than a 3 inch gear difference, enough that you'll have to work a little harder on the hills. And you'll gain a little at the high end. And you'll lose some gears that you would have with the triple. So why are you making the switch, to save some weight?.
The OP was extolling both the close-set ratio of his gears and the capability of almost never having to shift out of the middle chainring. But those are mutually exclusive concepts. If the cogs are close in number – e.g. 12-23 – then there are no easy gears for climbing in the middle chainring of a triple. And if the cogs aren't that close, then the ratio isn't that tight.
I almost never use the smallest chain ring on my triple. Maybe once a year I might use it. I use the 42 chain ring most of the time but will use the 53 on flats and declines. If I go to a compact, I can just use the 50 chain ring 98% of the time. I will rarely ever need to use the 34, only on really nasty hills. On a Campy 11 speed, the cogs are closer together so it shifts better. It also weighs less but that isn't what is motivating me to go to a compact.
There is probably a part of me that wants something that is new and cool too. My drive train is a mix of 2001, 2003 and 2006 stuff. It all works but a new compact group would be like having a new bike to me.