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  1. #1
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    Urgent Help: Top Normal XT on IH 6Point?

    Aight guys, this is kinda urgent, I have plans to ride tomorrow morning.

    Have an IH 6Point, was using SRAM X9 up until now.
    Not happy with performance, plus it broke, so, got Shimano XT RD-M772 Top Normal derailleur (this years') along with the new shifters.

    Got the drop out straightened at the shop.
    Mounted the derailleur, did the top adjustment, attached the cable.
    Now's the problem ... Can't shift all the way to the low position (biggest sprocket)!
    Activating the shifter only gets me to the 3rd lowest sprocket.
    I can pull on the cable / push the derailleur and it goes into the biggest sprocket, no problem.
    But the shifter can't do it.
    Screwing the adjustment barrel on the shifter all the way out gets me to the biggest sprocket, but then I can't go to the smallest one...

    WTF am I doing wrong?
    I've mounted plenty of low normal derailleurs before, never had this problem.

    Help appreciated!
    _B

    Edit: Just remembered that I have a SRAM cassette... That a problem? Reading other threads I seem to understand that the "No Mix Match" between brands is BS....

  2. #2
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    Reading your post carefully, I see that you replaced both the RD and control, so there shouldn't be a mix/match issue. The cassette is the same width, so that isn't the problem.

    It seems that the RD has enough travel, but the levers can only pull enough cable to move it half way, for either the upper or lower half of the cassette, depending on cable tension.

    A few places to look. First, double check that the lever set is in fact compatible with the RD and has the same pull ratio. Second, check that the lever has the full range of travel available, 8 clicks or 9 positions. Third, check that the cable is fully pocketed in the lever assembly and moves smoothly through all 8 clicks by holding it where it's bare, say along the downtube or where it emerges from the RD housing loop, and keeping finger tension on it. It has to have a definite incremental travel for each click in both directions, if it doesn't, locate the hangup and deal with it.

    If everything still seems correct re-attach the cable to the RD and try again, if the RD only moves half a cog width per click you have a pull ratio mismatch; if it moves one cog width per click for a few clicks and stops, you missed something and need to check again and locate the jam.

    Odds are that by the time you complete the 3rd test you'll have an Eureka! moment, deal with it and be riding in the AM.

    BTW- when I was involved sponsoring and supporting a road team many moons ago, I formulated Bollag's rule --- Never work on your bicycle in the 24 hours before a major race. When you get past this (either way) you might adopt it for the future.
    fb
    www.chain-L.com

    The key to solving any problem is to understand and address the underlying cause.

  3. #3
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    Eureka!



    Not quite my fault, but I still deserve a beating for the last-minute fix.
    So I go through everything step-by-step again.
    Just to make sure, I count the clicks in the shifter. Only 6. ****.
    Open it up, the lever that connects the shifter innards to the display is out of place and keeping the shifter from moving all the way.
    Fixed that, everything works fine now.
    Bought these new, no idea how it could've gotten out of place.
    Besides that, the shifters are fine (they're M770 Rapid Fire XTs btw).

    Thanks for the walk through!
    _B

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