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Thread: BMW final drives

  1. #1
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    BMW final drives

    Looked at a final drive failure on another web site, it appears that the 1200 GS has ball type bearings in the final drive, truthfully did not think anyone used them any more as roller bearings perform so much better. Has anyone converted their final drive to roller bearings.
    Just a question thanks
    2011 1200gs

  2. #2
    Polarbear Polarbear's Avatar
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    Also sealed!

    I just found out on my GSA1200'07. Never new the newer FD bearings were sealed and NOT run in oil. Mine just got replaced a month ago and I hand held the bearing in amazement, sealed! Randy

  3. #3
    Registered User David13's Avatar
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    I think they have to use the ball due to the lateral load. The needle can't take lateral load. Anton has a big write up about it. Something like lateral load.
    dc

  4. #4
    Benchwrenching PGlaves's Avatar
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    The original paralever drives had one deep groove ball bearing and one tapered roller bearing on the crownwheel. The new "big hole" paralever drives have one deep groove ball bearing and one cylindrical roller (needle) bearing on the crownwheel.

    If I had my druthers I would want a drive with two opposed tapered roller bearings or two angular ball bearings.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  5. #5
    A bozo on the bus deilenberger's Avatar
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    The original paralever drives also used preload on the tapered bearing, which has been hypothesised to be the cause of failure of the large ball bearing.

    The hexhead (big-hole) drives allow the drive to self-center with the ball bearing at one side and a needle on the other. IMHO - better design. Bearing preload is so easy to get wrong (as BMW proved..)

    BTW - ALL hexheads use this design, not just the GS..
    Don Eilenberger http://www.eilenberger.net
    Spring Lk Heights NJ NJ Shore BMW Riders New Sweden BMW Riders
    '07 R1200R (current ride) and some bimmers.. and a Porsche

  6. #6
    Polarbear Polarbear's Avatar
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    I don't know?

    BMW did preloaded bearings for 60+years, BUT of course the single sided swingarm changed all that with loading the rear wheel so differently. They sure have had their engineering difficulties regarding all this. Engineering may(?) be of sound quality and perhaps the bearing mfg'ers are the culprits? I don't really unbderstand a "sealed" ball bearing in my FD, with all that oil bath at hand? 180cc. Maybe not enough oil to keep bearing and gears all happy?

  7. #7
    Cam Killer marchyman's Avatar
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    Quote Originally Posted by Polarbear View Post
    BMW did preloaded bearings for 60+years, BUT of course the single sided swingarm changed all that with loading the rear wheel so differently. They sure have had their engineering difficulties regarding all this. Engineering may(?) be of sound quality and perhaps the bearing mfg'ers are the culprits? I don't really unbderstand a "sealed" ball bearing in my FD, with all that oil bath at hand? 180cc. Maybe not enough oil to keep bearing and gears all happy?
    Which would you rather have lubricate your bearings: clean grease of the appropriate type and amount; or dirty oil that may contain tiny abrasive metal bits sloughed off the gears through normal wear?

  8. #8
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    Quote Originally Posted by Polarbear View Post
    BMW did preloaded bearings for 60+years, BUT of course the single sided swingarm changed all that with loading the rear wheel so differently. They sure have had their engineering difficulties regarding all this. Engineering may(?) be of sound quality and perhaps the bearing mfg'ers are the culprits? I don't really unbderstand a "sealed" ball bearing in my FD, with all that oil bath at hand? 180cc. Maybe not enough oil to keep bearing and gears all happy?
    Are the newer final drives that are vented still using 180cc?
    Anthony S.
    2012 R1200GS

  9. #9
    Polarbear Polarbear's Avatar
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    Point taken:)

    A sealed bearing may well be a better idea! Who knows? After all, BMW FDs(bearings) have run in oil for a really long time. And, that said, they have been failing now, a lot of years too. I had never seen one, however, until recently when they showed me at the shop a sealed FD Ball bearing from mine. 180cc is likely the same, but you'd better check? I know mine does not get overly hot, as I can still touch it bare handed, no burns. Can't hold my hand on it long, because its still very very warm. FD Veteran here; 2 FD failed KLT1200, and now 1 FD GSA1200, maybe questionable! Dealer took NO chances, just did the job with very minor movement in rear wheel. Caught it early. Randy

  10. #10
    Registered User mneblett's Avatar
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    Quote Originally Posted by sloride View Post
    Are the newer final drives that are vented still using 180cc?
    Yes BMW lowered the fill on all the new drives -- the new K16 FD is also 180cc.
    Mark Neblett
    Fairfax, VA
    #32806

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