Shifting problems w/new compact crankset

[roadfix]

My guess is also a simple adjustment problem. There is really no reason why your set up can't be almost perfect.

[jenxxs]

Well, 9 hours of off-and-on fiddling later, I think I have it set up reasonably well. Turns out my indexing problem was caused by not tightening the cable enough - I also didn't realize the cable would have a larger effect on the cage shifts than the limit screws.

Thanks to all of you for encouraging me to try this myself - I learned a lot this afternoon by trial and error! Lots of error

[roadfix]

Well, 9 hours of off-and-on fiddling later, I think I have it set up reasonably well. Turns out my indexing problem was caused by not tightening the cable enough - I also didn't realize the cable would have a larger effect on the cage shifts than the limit screws.

Thanks to all of you for encouraging me to try this myself - I learned a lot this afternoon by trial and error! Lots of error

Glad you got this up and running. You can practically throw away the limit screws but if you don't have proper cable tension, nothing will work right.

[Rai Sue]

glad you found the easy fix of adjusting cable tension. Folks having chronic problems switching from the smaller chainring up to the larger chainring in the front may also want to look into seeing if their larger chainrings have pins and ramps.

Pins are little steel bumps on the back of your chainring (facing the smaller ring) which give a little boost to the chain. Shimano makes them, so you can change out the chainring to one with pins. It totally solved my problem of the chain not switching up, even when the derailleur and cable were adjusted.

Ramps i think are little divots in the back of the chainring itself which help facilitate lifting the chain up.

You can read more about it (and see a picture!) at http://www.sheldonbrown.com/gloss_ra-e.html

[jenxxs]

While I made sure to get new rings with pins and ramps (Stronglight), I have to say that the ramps aren't nearly as effective as those on the Ultegra ones I took off. Those ramps are huge, and they worked flawlessly. I'm sure Shimano also optimized their pins/ramps to work on their matched ring sizes.

Do other manufacturers of compact-sized rings (like FSA) have matched sets with really good pin/ramp systems? Since I was going with 48/34, which is not the most popular combination, I didn't try to look for a matched set.