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  1. #1
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    (New) Front derailleur hits large chainring OR chain on small chainring

    I finally picked up a front derailleur for my '09 Fuji Thrill LT and when attempting to install it, I can either get the small chainring to clear, or the large by moving it up or down the seat tube. There are no tilt adjustments, although this appears like it may be what I need to get it to clear on both sides. Either the bottom/tip of the derailleur, where the chain sits on the smallest gear, hits on the chain or the outer part of the derailleur hits the 44T chainring when I attempt to move up to the large chainring.

    I am using a SRAM X9 front derailleur and a SRAM S1000 22-32-44 crankset. There are no visible signs of the (new) front derailleur being bent where it goes to the mount. This configuration was used on the LT 2.0 model for the same model year, except they used an X7 derailleur. Tips?

    I tried pictures but apparently I need to use my SLR instead - they were all blurry due to the shiny silver frame.
    Last edited by Masejoer; 09-18-11 at 01:31 PM.

  2. #2
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    Sounds like you need to raise the height of the FD, have you looked at the manual which came with the FD, if you don't have one, you can get a copy from the SRAM tech docs site http://www.sram.com/service/sram/258,378

  3. #3
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    I understand how I should adjust it to the large chainring, but this causes a great bend in the chain as it hits the cage. I have to move it down to get the chain to clear down there but then it hits the large chain ring due to it not having the 1-2mm of clearance it needs.

    The derailleur looks fine when held up to the derailleurs on my road bikes - like it isn't bent.

  4. #4
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    What is the minimum difference spec on the front derailleur? For example , on an Ultegra or 105 it's 13T. That's the tooth difference you need between middle and large wheels so that the cage bottom can clear the middle when moving over to the large.

    If you don't meet the spec, you just have to move the derailleur up anyway and put up with a misadjusted top cage.

    KeS

  5. #5
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    Quote Originally Posted by kevin_stevens View Post
    What is the minimum difference spec on the front derailleur? For example , on an Ultegra or 105 it's 13T. That's the tooth difference you need between middle and large wheels so that the cage bottom can clear the middle when moving over to the large.

    If you don't meet the spec, you just have to move the derailleur up anyway and put up with a misadjusted top cage.

    KeS
    I have no idea. It is this derailleur: http://www.sram.com/sram/mountain/pr...ont-derailleur

    I can get it setup in a way where I can use both ends but can only use half of the rear gears on each cross-chain setup. No amount of tilting the derailleur one way or the other will get me any closer. I swear if the entire thing was rotated a little bit, every gear configuration would work without rubbing, but it would also be more likely to not shift properly. That's another thing - I can get it close but then shifting is a bit off and I have to use the shifter to give it a bit more movement to get up/down a gear. Perhaps it actually is defective/bent - I don't have another bike to actually bolt it onto. I could just let a LBS fight the issue Also I should add that the BB was installed properly by a LBS. The side marked drive side is behind the chainring.

    All I REALLY need is the bigger two chainrings - If only I could get all three to work well enough, I can deal with the cross chaining rear gears rubbing on the small chainring. If it was steel, I'd just bend the thing in places until it works to my liking. I just don't understand the issues though since my previous bike, which had a Shimano Altus front and currently used SRAM X9 rear managed to go into all 27 of its gears without even being close to rubbing anywhere. It used 24-34-42 chainrings though, and the same wheelset/cassette I have now.
    Last edited by Masejoer; 09-18-11 at 03:41 PM.

  6. #6
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    Either the bottom/tip of the derailleur, where the chain sits on the smallest gear, hits on the chain
    Is the chain on the small rear sprocket when this happens ?

    every gear configuration would work without rubbing
    There's no need to use every gear, some gears aren't meant to be used, some gear ratios are possibly the same and some would be so close in ratio that you wouldn't notice the difference.

    Don't cross chain and you probably won't have a problem.
    Last edited by cobba; 09-18-11 at 08:45 PM.

  7. #7
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    Quote Originally Posted by cobba View Post
    Is the chain on the small rear sprocket when this happens ?
    It's on the smallest 4 of the rear/9 speed cassette.

    Quote Originally Posted by cobba View Post
    There's no need to use every gear, some gears aren't meant to be used, some gear ratios are possibly the same and some would be so close in ratio that you wouldn't notice the difference.

    Don't cross chain and you probably won't have a problem.
    I understand that but I still don't know why this frame/front derailleur is giving me problems in more gears than it should.

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