I've been thinking of switching from a triple to a double on a 2007 Trek 1500. I have looked at some cranks on e-bay and noticed that most say 10 speed compatible. Will these also work with a 9 speed cassette? I'm not sure what else I would have to change. My bike has 105 shifters, an Ultegra long cage rear deraileur, a 105 front deraileur, and presently an Ultregra triple.

A 10-speed crank will work with a 9-speed cassette. But you will have to change your front shifter to a double.

Why? [ <-- not a frivolous or rhetorical question.]

Too much shifting and I'm sick of hearing that chain rattle. And everyone else seems to be making it up the hills around here just fine with a double. I know I can make the rattle stop with the second click of the shifter on the middle chain ring.

Thanks. What's the meaning of I thought Trek was the Trek of bicycles?

A double isn't a magic bullet. Honestly, a double is simple a triple with one ring amputated.


??? In other words, you use the granny. Try not using it and see how well you do. I ride with people that fly up hills. Doesn't mean I can fly up hills (or is that distinction too subtle?).


That's an adjustment issue. I know some mechanics adjust the FD so trim is required, but that's not necessary. A properly adjusted triple should shift just like a double - even better since the chainline on the middle ring is perfect.

https://www.bikeforums.net/showthread...29#post7377529
Number 2 and 8

Nope, 105 9 speed front shifter handles double and triple. Only 9 speed dura ace was 2 or 3 specific. Gonna also need an external bearing bottom bracket for your new crank. Might look around (Nashbar, eBay) and try to snag a NOS 9 speed 105r double crank for under 50 bucks)