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  1. #1
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    Dropped Chain on S-Works Epic

    Hello there,

    I've been having problems with dropping my chain from the big ring to the outside on my new S-works Epic with a XX, swingarm mounted front derailer. The front derailer is bolted in position and im not sure about a solution. Anyone else having this problem?

    Thanks.

  2. #2
    mtbr member
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    If the chain is coming off the outside of the big chainring then it sounds like you need to adjust the outer limit stop screw on your SRAM XX front derailleur in order to stop it moving so far outwards.

    http://www.sram.com/_media/techdocs/...ser_Manual.pdf

    Put the bike in the biggest front chainring and smallest rear sprocket and then screw the outer limit screw (A torx T25 bolt on the XX front derailleur) in just enough that the chain doesn't rub on the front derailleur cage. Test it and make small adjustments so that the derailleur moves far enough out that you can still shift from the small front chainring onto the big chainring.

    You can then fine tune the clearance of the derailleur cage and chain by using the barrel adjuster on the front shifter to get the front derailleur cage and chain as close as possible without actually rubbing. The front derailleur cage will hold the chain on and help stop it being thrown off.

    If your're riding very rocky sections a big ring front/ fairly large rear sprocket combination increases chain tension so it's less likely to get bounced off.

    Pictured below: SRAM XX front derailleur adjustment screws
    Attached Thumbnails Attached Thumbnails Dropped Chain on S-Works Epic-frontderailleuradjustment.jpg  


  3. #3
    dog lover-not in that way
    Reputation: 417markg's Avatar
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    It's been happening to me too; just started a few weeks ago. I've adjusted the derailleur and it's helped but hasn't stopped it completely. My LBS is getting me a new XX big ring under warranty because it has quite a few chipped teeth.

    It helps if you slow turn the cranks when going down the rough stuff. Also as soon as you notice the chain is off, drop the front derailleur to the lower gear and slowly pedal, it will bring the chain back.

  4. #4
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    Thanks guys. It seems that because the bike comes with a pretty small 39 tooth chainring and the system isn't adjustable up and down that the derailleur cage isn't low enough to stop the chain from coming off. This is excentuated by the derailleur being attached to the swingarm that moves slightly up and down possibly making the gap between the chainring and the derailleur cage even larger in rough terrain (where a chain is likely to jump off). Maybe this is why the factory team used a braze one front mech with a chain watch.

    Weird how Specialized couldn't use a braze on style for the rest of us and we have to deal with chain dropping issues on a $8800 bike.

  5. #5
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    If the problem is that the chain is being bounced off the chainring (as opposed to an upshift from small to big ring throwing the chain off due to the front derailleur moving too far outwards) then it's really a case of trying to increase chain tension. Have you tried taking a link or two out of the chain?

    Something I thought was quite interesting was this comment in Bikeradar.com's first ride report of the new SRAM X-0 2011 components:

    "Chain management in rough terrain is also better than on XX, with what feels like a stiffer cage return spring" Bikeradar.com

    http://www.bikeradar.com/news/articl...e-review-26550

    With the front derailleur alignment you could try being more aggressive on setup also. Rather than have the front derailleur not rubbing in the big ring/ smallest rear sprocket you could adjust the front derailleur inwards so that it still rubs a little in top gear. This should help encourage the chain to stay on the chainring by acting as a guide.

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