Dual disc frt. brk., would this work?

Discussion in 'Old's Cool' started by Motomech, Dec 7, 2006.

  1. Motomech

    Motomech Adventurer in Latin Amer.

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    Ok, I've been looking at the two parts bikes in my carport and wondering if I couldn't use two stock right fork legs, two stock rotors and two stock calipers to make a dual disc frt. brk. Everything is symetical and looks like it would bolt up ok, the lower fork leg on the left side being turned around to have a trailing caliper, as opposed to the original leading caliper. But there is the problem of the master cyl., master cyl.s for dual disc set-ups have a different hydraulic ratio. Any sugestions for a BMW dual disc master cyl. that would be suitable to use on a GS?
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  2. datchew

    datchew Don't buy from Brad

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  3. R-dubb

    R-dubb Dubbious Adventurer

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    Having recently wrestled with the same issue, I decided against it. One very simple issue is you will have a hard time finding a caliper. They are not reversible. The similar dual disk, Brembo calipers that BMW used during this period have a smaller piston. (I have a pair, and a pair of matching rotors with four holes that fit the GS hub if you are interested.)

    The primary reason I decided against it is unsprung weight. It adds quite a bit. It is more efficient (and easier)to upgrade to a four (or six) pot caliper and a larger rotor. I actually could have pulled off the dual disk set-up more easily since my HPN forks have mounting tabs already on both sides! Still decided to go the upgraded single disk route.
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  4. Motomech

    Motomech Adventurer in Latin Amer.

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    Thanks for link. I can see I could only use the lower fork legs and would have to scrounge everything else. Yes I agree, better to use one of the more common brk. up-grades.
    Thanks
    #4