I don't know what your hills are like or how strong you are, but I do know that when I decided to get a compact double on my new bike, I spent a lot of time looking at Sheldon Brown's gear ratio chart. I wanted to be sure a compact double would have the gears I need. Where I ride is downright hilly, maybe verging on mountainous...

I'm a lazy ultra distance rider. I typically don't pedal down hill if doing 25 mph. On the flat I can reach 25 mph, but it certainly isn't sustainable. So I don't need a huge gear. I went with a 46 - 33 and a nine speed 11 - 34 cassette.

I guess what I'm saying is, think about what you really want this bike to be able to do for how and where you ride. And maybe just buy lighter wheels for your tri bike so you can set this bike up as a climbing bike, if you want.

V.