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Discussion Starter · #1 ·
I've got a 50-34 Ritchey WCS (yes, I've had the recall swap done), with a 9 spd 12-27 ultegra rear cassette and Ultegra ders.

When I'm in the 50, I get chain rub against the front der in the largest four cogs (27-24-21-19) and when in the 34, get chain rub against the front der in the four smallest (12-13-14-15). This is highly annoying and I hope not normal.

Thoughts?
 

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You can try and move your front deraileur over with your barrel adjuster either at the shifters or on your down tube. This will fix some of the problem. But you should keep in mind that with some of those gears you are cross chaining a bit. You can achieve the same gear ratio by dropping from the 50 to the 24 and going down a couple of cogs in the back. Try adjusting your barrel adjuster though. That should move it a bit. Check to see that you dont have extra slack in your cable as well by dropping your deraileur into your 34 ring and seeing if the cable is taught or slack. If it has slack, loosten the allen bolt and tighthen the cable. Then play with your barrel adjuster. Winding it counter clock wise will move the front deraileur away from the frame, while clockwise will move it towards the frame. When you are spinning it, think of it as a screw or spoke nipple and you'll turn it in the right direction.
 

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Discussion Starter · #3 ·
superflychief said:
You can try and move your front deraileur over with your barrel adjuster either at the shifters or on your down tube. This will fix some of the problem. But you should keep in mind that with some of those gears you are cross chaining a bit. You can achieve the same gear ratio by dropping from the 50 to the 24 and going down a couple of cogs in the back. Try adjusting your barrel adjuster though. That should move it a bit. Check to see that you dont have extra slack in your cable as well by dropping your deraileur into your 34 ring and seeing if the cable is taught or slack. If it has slack, loosten the allen bolt and tighthen the cable. Then play with your barrel adjuster. Winding it counter clock wise will move the front deraileur away from the frame, while clockwise will move it towards the frame. When you are spinning it, think of it as a screw or spoke nipple and you'll turn it in the right direction.
Thanks!
 

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you could also try...

Look on the shimano site for the technical docs for you derraileur. You probalby have an issue with your stop points, set by the two philips screws on the top of the derraileur. Adjusting this would probably help a lot.
 

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I trust you know a thing or two about trim?

LyncStar said:
I've got a 50-34 Ritchey WCS (yes, I've had the recall swap done), with a 9 spd 12-27 ultegra rear cassette and Ultegra ders.

When I'm in the 50, I get chain rub against the front der in the largest four cogs (27-24-21-19) and when in the 34, get chain rub against the front der in the four smallest (12-13-14-15). This is highly annoying and I hope not normal.

Thoughts?
 

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The barrel adjuster will set the derailer's position in the outer chainring (provided the upper limit stop allows that much travel), and the lower limit stop screw will set the derailer's position in the lower chain ring. The upper limit stop screw will set how far you can overshoot the outer position when shifting to the outer ring.

I adjusted mine by setting the barrel adjuster so there was just barely no rubbing in the big/small combination, then the lower limit stop so there was just barely no rubbing in the small/big combination. I have no rubbing on the derailer in any combination now, but the bottom of the chain rubs the big chainring in some of the small/small combinations.
 

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Won't your trim help that? I never have any rubbing, in any combination.

russotto said:
The barrel adjuster will set the derailer's position in the outer chainring (provided the upper limit stop allows that much travel), and the lower limit stop screw will set the derailer's position in the lower chain ring. The upper limit stop screw will set how far you can overshoot the outer position when shifting to the outer ring.

I adjusted mine by setting the barrel adjuster so there was just barely no rubbing in the big/small combination, then the lower limit stop so there was just barely no rubbing in the small/big combination. I have no rubbing on the derailer in any combination now, but the bottom of the chain rubs the big chainring in some of the small/small combinations.
 

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Discussion Starter · #8 ·
filtersweep said:
Won't your trim help that? I never have any rubbing, in any combination.

I broke down and I'm now having my LBS install a completely new SRAM drivetrain (Force shifters and rear der, Rival front der, cassette and chain). I was able to get the whole set, new, on eBay for $500.

Not switching b/c of the rubbing, but b/c the DT had at least 25000 miles on it, and I really like the SRAM stuff on my MTB.
 
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