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  1. #1
    Ride Responsibly
    Reputation: LWright's Avatar
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    Guide Pulley Lateral Movement?

    As I understand it, the Guide or upper pulley in a rear derailleur has some built in side to side movement. Is this correct? And the lower or tension pulley has no side to side movement.
    This seems backasswards to me, as the guide pulley lateral play would require more movement of the derailleur to shift gears. If their was no side play in the guide pulley, would it not shift better?

  2. #2
    meh....
    Reputation: Monte's Avatar
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    That's the way Shimano does it. SRAM doesn't have any lateral movement in the upper wheel. If you think it's wrong, install a fixed one if you want.

  3. #3
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    Reputation: Bikinfoolferlife's Avatar
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    It's that very feature that made the Shimano derailleurs shift better than the competition way back when...but it's the upper pulley that helps make small adjustments to cog position for indexing which is it's purpose.
    "...the people get the government they deserve..."
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  4. #4
    Former Bike Wrench
    Reputation: mtnbiker72's Avatar
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    The floating pulley allows a little margin of error on the adjustment of the rear derailleur. Since Shimano uses a 2:1 pull ratio, any adjustment issues are magnified 2x. By using a floating pulley, this somewhat alleviates this amplification. SRAM does not use one because their 1:1 pull ratio allows for a little more margin of error.

  5. #5
    mtbr member
    Reputation: jekramerjr51's Avatar
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    pulley play

    so.........to make a long story short,there IS sapposed to be play in the bottom pulley of a sram rear derallier? if so,how much? i have a nine month old sram x7 that i maintain (along with the chain)religiously due to the wet and muddy conditions of oregon.i was curious on the life of the pulleys? thanks for any comments or suggestions.

  6. #6
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    yup the shimano pulley has a little side to side play upper one...

    I changed out to some different pulleys with no side to side play...can't really notice the difference...

    I run XTR..

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