Originally Posted by DogBoy
I fall into the: 2) too fat category, and I thought about putting a compact crank on my tri-bike (coming in January). I run a triple on the road bike and occasionally need to bail from 42-25 to 30-23. I figure that running a 50/34 would get me bailout gearing without giving up much on the top. I rarely spin out, but I only race tris, so there is no need to sprint. A 50:12 is more than enough big gear for me. The only reason I haven't done it is because I'm a little concerned about chainline issues since the stays on my tri-bike are very short. I decided to stick with the standard 53/39 and go with a 12/27 cassette for now. If I can't handle the hills with that, I will think again about the compact crank with a triple front derailleur and a midcage rear derailleur, or whatever combination it takes to get it to work properly.
But before I do any of that, I will just super-inflate my rear tire. I hear that negates the effect of gravity
your 53/39 double with 12/27 will be slightly easier to pedal up hills than a compact crank(50/34) and 11/23 cassette.
34/23: 38.8 gear inches
39/27: 38.0 gear inches
So Galen, what's this about a compact being easier than a 39/27 double. It's not! That's the reason I wrote this thread........to dispel the BS out there!
A 50/33 compact is essentially equal to a 53/39 double with 12/27 as far as hill climbing goes, but with much tighter progressions.