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  1. #1
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    New question here. mysterious shifting problem... new RD and inaccurate shifting

    Just last night my new SRAM X.7 short cage came in. I previously had a long cage X.5, with X.5 shifter. after I mounted the short cage... using the same chain, same cassette, and same shifter I CANNOT get the derailleur to shift cleanly. It clicks and grinds like it's trying to jump a gear, but not quite. Or it will skip up the cassette by a gear or two ( when going to low gears), and shifting into higher gears ( moving to smaller cogs), there is a significant delay in the shift. Is it just worn parts? is there something I screwed up?

    before you ask, it is a 1x9 with a 32 x 11/34, and according to the charts, I shouldn't be even close to the limit of the short cage. BUT when I have it on the 34t cog, the RD looks like it is REALLY close to being overextended.

    any thoughts?
    ~Max
    I'd be unstoppable... If I could just get started !!

  2. #2
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    Same size chainring too? I'd check the derailleur hanger. It's possible you could have bent it when working on the bike. I assume you've eliminated tension adjustments as the source of the problem.

  3. #3
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    After mis-aligned hangers, the main cause of the type of erratic shifting you describe is cable friction.

    Friction within the housings causes the wire to overtension and jump when downshifting, and hang when upshifting. You might be able to get a sense of how stiff the cables are by removing the rear wheel and shifting the RD in and out while watching for how smoothly it moves.

    Another test is to try to upshift one gear, and if it hangs pluck the bare wire away from the frame like a guitar string. If that corrects the delay it's definitely cable friction which you overcame by plucking.
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  4. #4
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    thanks for the info and ideas. guess when I get home from work I'll check the hanger. I doubt that its cable friction, 'cuz the routing didn't change at all. but maybe because its a short cage it is more sensitive than a long? hmm... more to look into
    I'd be unstoppable... If I could just get started !!

  5. #5
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    Reputation: savagemann's Avatar
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    You may have routed the cable incorrectly through the pinch bolt on the rear derailluer.

    Depending on what year the derailleur is, it will have a different routing. And different models have different routing as well.
    Here is an older diagram of an example.
    Check the data sheet that came with the mech, and make sure you did it right.
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  6. #6
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    The newer RD's have a different cable anchor routing that what savagemann posted.

  7. #7
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    no its not incorrect routing. and frdfandc, I believe that you are thinking of the new xo/xx line, cuz the X5 and x7 are still the same.

    I think I traced the problem to the hanger bolt. I noticed that it has a ton more play than the one on the x5. the bolt on the x5 only moves the smallest little bit, but on the x7 it has about 2mm of play. So when the RD is mounted, and the hanger bolt tightened up to spec, the entire RD has that 2mm of play on a horizontal axis. I fashioned a rubber washer out of a piece of old tube and sandwiched it between the hanger and the RD to take up the extra space. It didn't work miracles, but it significantly improved function, enough that I'm happy with it.

    thanks again for all the help, I'll report back if the problem persists, or gets worse.
    ~Max
    I'd be unstoppable... If I could just get started !!

  8. #8
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    This doesn't sound like your problem, but might be. I got an x.7 medium cage 6 months ago that was very sticky in action, especially in the smaller cogs. A few others posted the same issue. I swapped it out for my old X.9 long cage and my shifting problems went away.

  9. #9
    Bike Addiction
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    I got a 2010 X7 long and returned it. Spring didn't want to pull it back to last 3 cogs. Had the LBS look at it. They sent it back to sram and as soon as they warrantied I asked for my money back. Had an 08 X7 and it worked great just broke it off on a rock.(Oops) Either going X9 or Shimano.
    Disclaimer: Always get a second opinion cause I'm just guessing

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