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  1. #1
    mtbr member
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    shift skips a gear (not the usual ghost shift or adjustment problem)

    It all worked fine until the chain broke. Everything was worn, so I ended up replacing all drivetrain components except the RD. I have Shimano dual shift/disk levers and XTR RD. The problem is that now it shifts all 9 gears in 7 clicks, as if it was an 8 speed. The last click does nothing because the limits stops are set correctly. So it skips a gear in the middle. The cable shifts smoothly and the exact same amount for every shift. The RD moves the same amount for each shift, with or without the rear wheel on. It's like the shift lever decided to move the 8-speed gap distance, even though it still has 9 positions. The RD bracket is not cracked or moving. The RD is reasonably aligned, and no unusual play in the mechanism. I put the old cassette back on and it still does it. Can something bend in the RD that is not obvious but would change the distance it moves? Can something wear or break in the shift lever that would cause this? Or does the lever have some way of changing between 8- and 9-speed modes? I'd like to figure this out before throwing $$$ at it. Any ideas?

    Stumpjumper Pro 120 2005
    Shimano M765 dual levers and disk brakes
    Raceface chainrings (new)
    sram pg-980 11-34 cassette (new)
    sram high-end chain (new)
    XTR RD
    Shimano cables and housings (new)

  2. #2
    Two wheels are best
    Reputation: DM-SC's Avatar
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    Have you checked to make sure the rear derailleur hanger is straight? Depending upon the load when the chain broke, it could have bent the hanger...
    Never be afraid to try something new.

    Remember amateurs built the Ark.
    Professionals built the Titanic.

  3. #3
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    Yup, it's straight and solid. I'm thinking it's in the shift levers, but it seems to work perfectly too.
    Thanks!

  4. #4
    Wrench
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    Disconnect the cable and hold it tight. Shift through all the gears and make sure you're getting 8 index clicks for your 9 gears. If you're not getting the 8 clicks then your shifter is probably broken. The rear derailleur shouldn't have anything to do with it as long as its straight.

  5. #5
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    The problem was that I got a 1.2mm replacement cable. The original was 1.1mm. That extra diameter caused the cable to ride up high in a groove in the shifter that the cable winds on. That made it shift more for each click than it was supposed to. It is a Shimano and a Shimano replacement cable so i'm really pissed. It took weeks to figure it out. The bike is an '05, so I would hope they widened the groove shortly after that. I guess not too many had a problem like this.

  6. #6
    It's about showing up.
    Reputation: Berkeley Mike's Avatar
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    Thanks for publishing the solution.

    I was questioning the spacing on the cassette because I could think of nothing else.

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