I recently installed a set of 52/36 Q-Rings onto my Cervelo S2. For the life of me...I can't get a good shift onto the big ring. This setup was on a different bike using a clamp adapter...and the shifting was great. Now that I moved it onto my Cervelo...it will not shift properly onto the big ring. It shifts fine on the stand...soon as I get on the bike and shift...the chain will feel like its not catching onto the lift pins. Chain is slipping on the back of the large chainring.

I have the limit screw set at the limit...any more it will pop the chain off onto the crank.

I have the FD setup as per the Rotor instructions. They mention a "shim" has anyone actually used that?
SRAM Braze-on Front Derailleur washer for compact crank - www.neuvationcycling.com

I had a 53/38 round rings before and that shifted fine.


Thanks!

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Rotor rings are not the best, but if unsure take it to a bike shop.

This shim saved me... This is doing all the job. Use it and everything will work.... It change the angle of the FD. It solves the problems..

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My Builds so far... C50,EPS Erik Zabel, C59 Di2.

I have never had any problems with shifting on my QRings with Red FD. I just recently changed to the 2013 Red FD and it is as smooth shifting as ever. As long as you know how to set up your FD properly then you should have no issues. Once you get it dialed in you will be happy!

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mySWORKS
myCERVELO
myBMCRM01
myBHultralight

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OMG

Typical adjustment settings are for the outer cage to be parallel to the big ring, between 1 and 3mm above the big ring. Try this instead:
Raise the cage to 3.5mm above the big ring, and tilt the tail of the derailleur cage about 0.5mm inward. This setup was shown to me by a SRAM insider (Ed, for those in the industry) and although I don't use it all the time (line between rubbing in the big ring and ability to throw it off the outside is a bit tighter), it often does the trick.
If the setup works for you, but as I mentioned it's near impossible to not have the derailleur overshift off the big ring, try bending (straightening) the front part of the outer cage plate a little narrower.

Look here>> Luke 23:34