Originally Posted by
mtnclimber
I'm relatively new to the gearing scene. I have two road bikes, a BH Connect carbon frame with Campy Centaur, and a Cannondale R800 aluminum frame with Shimano 105. One reason I have two road bikes is to have two different sort of rides.
I have consulted Campagnolo's gear calculator, so understand on paper the difference in gear inches between the two, and have also compared different cassette ratios (11-25, 13-26 etc) between the two cranksets. What is likely to give me the most useful ratios and (both crankset and cassette) considering the above?
A triple on the Campagnolo bike. I like 50/40 big and middle rings with a 13 starting cog where 50x13 is still a 30+ MPH cruising gear and 35+ MPH sprinting gear (any faster down hill I'll just coast). Pick an inner ring to suit your terrain. I rode 50-40-30x13-14-15-16-17-18-19-21 in the Colorado Rockies and liked it a lot more than the 50-34x13-14-15-16-17-18-19-21-23 I ended up with as I replaced a worn out crankset and cogs.
You can get a few gears lower than a compact (smallest inner ring is a 24 versus a 33) without compromising spacing for riding on flat ground for the same or even increased range (I really like one tooth jumps up to the 19 cog).
You'll have less double shifting in rolling terrain. 40x23 through 40x14 cover 11-22 MPH while with the compact double 34x14 runs out about 19 MPH and you don't use the 50 ring below 15 MPH.
When you do need a double shift the next gear will be 3 away (one wiggle of a non-escape, non-Powershift Campagnolo lever in either direction) instead of 4 with 53-39 and 5 with 50-34.
There will be less chain noise because you'll be riding gears like 40x17 in the middle of the cassette instead of 50x21 or 34x14. You might get more chain life (Campagnolo chains seem to develop excessive side clearance and degraded shifting performance before they stretch too much) .
The left shifter will handle it especially if you don't have the 2007-2008 Escape or 2011 Powershift mechanism that lacks trim.
A NOS Campagnolo triple crank off E-bay plus derailleurs can also be less expensive than just a NOS Campagnolo compact.