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  1. #1
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    x7 rear derailer question

    Why are the derailer pulleys not parallel to the face of the rear wheel?
    The chain clears the tire at the top but touches on the bottom as if the lower sprocket on the derailer is in further than the rear cassette.

    Can the derailer be adjusted or it it an issue with the hangar?

  2. #2
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    Quote Originally Posted by Boatracer View Post
    Why are the derailer pulleys not parallel to the face of the rear wheel?
    The chain clears the tire at the top but touches on the bottom as if the lower sprocket on the derailer is in further than the rear cassette.

    Can the derailer be adjusted or it it an issue with the hangar?
    Sounds like a bent hanger - any pic's ?

  3. #3
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    I dont have any pics that would actually show the scenario everything is new bike was never dropped or banged up is it normal to have to adjust the hangar?
    Is there a procedure for aligning the hangar?

  4. #4
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    Quote Originally Posted by Boatracer View Post
    I dont have any pics that would actually show the scenario everything is new bike was never dropped or banged up is it normal to have to adjust the hangar?
    Is there a procedure for aligning the hangar?
    Not unusual for the hanger to need alignment.

    You need a hanger alignment tool. A good shop will have one.
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  5. #5
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    People who put it together didn't check the hanger. Often times, it comes out of the box bent.

    Is the bike new from a shop? If so, bring it back and have them align it. If not, alignment is not difficult with the proper tool, and can even be accomplished by eyeball if you are desperate. Insert a long 5mm hex wrench into the attachment bolt, cradle the other side of the derailleur, including the hanger, and use the wrench as a lever to bend the hanger.

    You can also use a spare rear wheel with a threaded axle, run into the hanger in place of the derailleur (the thread pitch and size is the same). Measuring from one spot on the rim to one spot on the other rim using this method in several places, until all are equal, can be just as accurate as using the proper tool.

    You must do either method with a rear wheel locked in the dropout, as this affects the alignment.

  6. #6
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    Quote Originally Posted by wschruba View Post
    You can also use a spare rear wheel with a threaded axle, run into the hanger in place of the derailleur (the thread pitch and size is the same). Measuring from one spot on the rim to one spot on the other rim using this method in several places, until all are equal, can be just as accurate as using the proper tool.

    You must do either method with a rear wheel locked in the dropout, as this affects the alignment.
    In order to straighten a derailuer hanger properly, the rear wheel must be trued. Your method further complicates this problem by adding another wheel to the mix. But great idea, very good thinking :-)

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