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  1. #1
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    Reputation: Dirthugger's Avatar
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    Derrailleur jumping gears

    Im not sure if this should be posted on Drivetrain thread. But I decided to post here since its happenning on my Trance X and with an XT shadow RD.
    I experienced this problem this weekend, whenever I hit a 1-2 feet drop the derrailleur jumps gears. Is this an issue or normal operation for the mech. Or is it an issue with the frame it seems to only occur when I hit some jumps. And I know Im not accidentally hitting the shifter lever.
    Is this a normal occurrence? Is it a frame issue when the swingarm compresses should it affect the rd mechanism?

  2. #2
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    Reputation: EGF168's Avatar
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    [SIZE=2]The Trance X naturally suffers from more chain slap than others because of the design which might cause it to shift when it hitís the ground but I donít generally end up doing that much flying on it so I've only ever noticed a lot of chain slap going off kerbs and stuff.

    Does it shift well normally?
    [/SIZE]
    Last edited by EGF168; 05-28-2008 at 04:06 AM.

  3. #3
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    That isn't normal and sounds like a cable routing/length issue.

  4. #4
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    Deadbolt, Ive considered that as well I went to a lbs to view a Trance XO setup and my cable setup is the same. Since I built it myself i wanted to make sure it was correctly routed.

    Actually I dont quite understand it Ive had this bike for 6mos and ride twice a week. This weekend was the first time it started doing this. And nothing has changed I didnt make any component replacement just the regular cleaning, brake and derrailleur adjustments.

    I guess im comparing this syndrome since I never experienced it with my other bikes. An old GT LTS, KHS AM2000, and a Turner 5 spot.

    Maybe a third eye by a lbs mechanic might find an issue with my bike setup?

  5. #5
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    I've seen this from cable stretch. Your shifting may just barely be right, but when the suspension compresses and flexes the middle portion of housing, the cable tension changes just enough to make a shift and then back again. I have also noticed that this problem seems to get worse when 5mm housing is used instead of 4mm in the center, active portion of housing. Try turning your barrel adjuster 1/4-1/2 turn counter-clockwise to compensate for cable stretch and see if it helps.
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