Bicycle Mechanics - FD/crankset/chain compatibility on a CX

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LBIkid
02-23-09, 06:14 AM
I recently had my LBS swap out an LX touring triple (48-36-26) with an Elita Cross double (48-34). Like the new crank, but the bike doesn't shift as well anymore. My current set-up is:

Elita 10 speed crank
Shimano HG93 9 speed chain
Dura Ace bar end shifters w/Pauls Thumbies and
older LX FD sized for a 48T max big ring

No matter how I adjust the limiting screws on the FD, the chain is rubbing. Even using the friction shifters, I can't seem to dial it in. Any suggestions?

Do I need a narrower 10 speed chain? Do I need a road double 10-speed FD? Do I need a new LBS?

cachehiker
02-23-09, 03:10 PM
I eventually went to a road double FD to accomodate the 14-tooth difference. The LBS said it would work and I can't say it didn't. However, if absolutely no rubbing was the object, I only had 6 of 9 cogs on both rings. After making the change, I have 8 of 9 but rarely use the 8th.

Was your FD originally designed for an 8 speed or a 9 speed drivetrain? If it's an old 8 speed FD, the little bulge in the middle of it was tuned for a 10 tooth jump and will usually work with 12, but 14 sometimes requires a lot of fiddling and still never works quite right.

Is your chainline set up to match to your derailleur? Is the distance of the seat tube CL (center line) to inner ring CL the same as the seat tube CL to middle ring CL used to be? I'd probably be running the FD very close to the outer chainring too.
AEO
02-23-09, 03:52 PM
are the rings bent?

LBIkid
02-23-09, 06:12 PM
No, I don't think the rings are bent.

The chain line may be a good place for me to look. Otherwise, I guess its a new FD?