Countershaft sprocket bolt dimensions? Anyone know the stock size?

Discussion in 'Parallel Universe' started by lookaught, Mar 12, 2014.

  1. lookaught

    lookaught Loner Extraordinaire

    Joined:
    Jan 19, 2010
    Oddometer:
    198
    Location:
    Lander, Wyoming
    The bike I bought had a used, bent, class 8.8 (which is the equivalent of a Grade 5...) bolt installed by a BMW dealer in place of the OEM counter shaft sprocket bolt.

    I would like to order a replacement in my order with McMaster Carr, but am not sure of the proper dimensions and I'm not near my bike to measure. I seem to recall it's an M10 (or maybe M8), but I don't know the proper length or whether it should be flanged or not. The closest BMW dealer is 4 hours away, so I can't just pop over and order one.

    So if anyone knows this info, sharing would be appreciated!

    The bolt that came out...
    [​IMG]
    #1
  2. sarathmenon

    sarathmenon Armchair Adventurer

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    IIRC, it's M8 for pre2010 and M10 post 2010. My 2012 has an M10 FWIW.
    #2
  3. lookaught

    lookaught Loner Extraordinaire

    Joined:
    Jan 19, 2010
    Oddometer:
    198
    Location:
    Lander, Wyoming
    Dammit, I have a 2010 so I guess it could be either. I suppose I'll have to wait to measure the temporary replacement I put in when I get home.

    Any idea if the oem is flanged or not? My bike had two washers, one was a centering washer the other was a spring washer. I'm guessing I could use either a flanged or non-flanged, but would like to order the appropriate one if someone knows.

    Thanks for the input.:freaky
    #3
  4. itsatdm

    itsatdm Long timer

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    The stock bolt is not flanged, at least on the 2009 model, and the 2 washers are stock.
    #4
  5. Reaver

    Reaver Outta Here

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    #5
  6. lookaught

    lookaught Loner Extraordinaire

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    Jan 19, 2010
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    Location:
    Lander, Wyoming
    #6
  7. Reaver

    Reaver Outta Here

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    Both Max and A&S BMW have a parts fiche on their site. Max's seems better but sometimes A&S will have more info. I just cut and paste PN's for my email order at the local Dealer so parts boy doesn't get all frazzled and get me an airhead part.

    That and when you forget what bolt goes where after an all nighter, you can get the dimensions online to sort it out.
    #7
  8. FredRydr

    FredRydr Danger: Keep Back 500 Ft.

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    LOL So true! However, if you ever get to Hermy's BMW along I-78, their BMW parts guy seems to have memorized half the bolts, and can recognize the other half if you show one to him!

    Fred
    #8