Airhead mono final drives

Discussion in 'Airheads' started by Airhead Wrangler, Jul 1, 2010.

  1. Airhead Wrangler

    Airhead Wrangler Adios Mexico

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    Couple of questions for those who've been there / done that. I'm doing some long term planning for a revamp on my bike and was considering a slightly higher final drive ratio in order to save a bit of gas and maybe get a little more speed. I was wondering if the later Monolever final drives have the same spline as the earlier G/S and ST final drives. Also, will a later GS 4 lug wheel mount up to the monolever 4 lug final drives? I'm betting StephenB can shed some light here.
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  2. Caddy82rats

    Caddy82rats Long timer

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    For example a 1989 monolever rear from a RT will fit.
    Four lug has the same patern but wheel ofset is totally not the same
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  3. Airhead Wrangler

    Airhead Wrangler Adios Mexico

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    The offset of the rim in relation to the hub or the offset within the hub itself?
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  4. StephenB

    StephenB G(/)S ... what else!

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    Sure can do!

    G/S and ST have 3-lug final drives, both with the known 37:11 ratio. Acc to the ETC there are further crowngear sets available in 32:9 (R65 I believe) and 32:11 (Swiss model, Joerg should be able to confirm).

    4-lug final drives can be had in 33:11, 32:10 and 37:11 (33:11 is the nicest on a 1000cc engine for street, IMHO).

    Input FD splines are all the same.

    All 4-lug monolever FDs work with the 4-lug GS hub (see link below) and whatever you lace to it, obviously ;-)

    Two relevant links:

    Paralever -> Monolever conversion: http://www.stephenbottcher.net/BMW/paraconv.htm

    Spoked wheels on a monolever:
    http://www.stephenbottcher.net/BMW/rearconv.htm
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  5. Caddy82rats

    Caddy82rats Long timer

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