Originally Posted by
PhotoJoe
In all of my reading here, one of the reasons people say they prefer the double over triple is that it shifts so much better. If I were to convert a triple to a double (say, bonktown Ultegra double compact), leaving the shifter as a triple but adjusting whatever needs to be adjusted so it thinks it's a double, would it still shift as well as a real double setup. I keep seeing all these triples on CL and it got me wondering. What part of the system makes a double shift so much better? Or, is it the entire system as a whole?
My triple had better rear shifting than the double which preceded it with the same overall range (50-40-30x13-21 versus 52-42x14-28, with the one tooth jumps being a lot smoother (I realized that I could have a straight block for flat terrain plus climbing gears without changing cassettes or wheels; the setup rocked).
My triple front shifting was better than the double which followed it (50-34) but that was probably as much a function of the better pins and ramps on the Campagnolo triple rings versus the FSA double rings as the smaller difference between chain rings (I switched because I wore out my chain rings, 34x23 is the same low gear as 30x21, and I believed the hype about doubles being better).
The triple was quieter too since I could cruise in cogs closer to the middle of the cassette instead of the ends. With 50-34x13-14-15-16-17-18-19-21-23 I spend a lot of time cruising around 17-19 MPH in 50x21 and 34x14 one in from each end of the cassette while the 40 middle ring on the triple let me use the 16 or 17 cog which is right in the middle.
I wouldn't choose a double unless I could have a low enough gear while still running one tooth jumps up to the 19 cog and had a small ring big enough to cruise in.