'83 flywheel and clutch "Plug N Play" on a '78???

Discussion in 'Airheads' started by swanker, Oct 31, 2012.

  1. swanker

    swanker Shadetree Tinkerer

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    Columbus, Ohio
    Inspired by a reply in this thread http://www.advrider.com/forums/showthread.php?t=837268 I thought I'd start a new one to specifically find out what is involved.
    It caught my eye because I have a '78 R100/7 and also a '83 R80RT parts bike and have been interested in lightening the R100 flywheel.
    Could this be nearly as simple as a swap out?
    I'm noticing a fair amount of false neutrals especially from 3rd to 4th and 5th to 4th, 4th to 3rd which having a spare tranny/clutch on hand makes me even more intriqued.

    Thoughts?

    from http://www.advrider.com/forums/showthread.php?t=837268
    #1
  2. Wirespokes

    Wirespokes Beemerholics Anonymous

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    It would take swapping the flywheel (called a clutch carrier on the newer ones) clutch pack, and transmission. Sounds like you've got all the parts - go for it!
    #2
  3. disston

    disston ShadeTreeExpert

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    You don't really have a spare transmission, wording is tricky. The '78 R100 bike has a long input shaft transmission. The '83 R80 bike has a short input shaft transmission. The two transmissions go with their respective flywheel/clutch set ups. You can change the transmissions if you also change the flywheel/clutch. So sounds like you get what you want out of this. The lighter clutch carrier and a working transmission.

    The lighter clutch swap is a performance improvement many desire. I'm not sure but you may notice some more engine vibration.
    #3
  4. Airhead Wrangler

    Airhead Wrangler Long timer

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    Most people note the revvier feel the lighter clutch carrier gives, but I'd say the bigger benefit is lighter lever pull and a clutch that's not right on the edge of slipping (if not slipping) when you "give it the beans." It's just a better functioning clutch as well, not just lighter.
    #4
  5. supershaft

    supershaft because I can

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    Night and day better IMO.
    #5
  6. Beater

    Beater The Bavarian Butcher

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    +1. I love the looks of those /5's and /6's ... but after riding a monolever, I'm sold on the technology. It's a night and day better ride.
    #6
  7. carpetburn

    carpetburn Been here awhile

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    Definately worth the swap
    #7
  8. supershaft

    supershaft because I can

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    +1

    Besides, I honestly like the looks of a Monolever more than a /5 or /6. When I look at /5's and /6's, I can't get over how much better a Monolever works.
    #8
  9. mattcfish

    mattcfish R90X

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    I agree, the post 81 clutch is much better and performance is improved. I did it to my 75 R90 using an 83 tranny.
    Another reason an early, long nosed input, tranny doesn't work well with the later clutch, is the travel for the clutch activating rod is too short. The later trannies have a much different lever and rod configuration.
    And don't forget that you need a 9 tooth starter.
    #9
  10. Boxer Metal

    Boxer Metal Mad Scientist

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    Measure the flywheel height at the center and see if it is the same as you 78 flywheel. If not you will have to change out the thrust washer to insure you have the correct end play. This is a fantastic conversion. I just did one on a 76 /6.
    #10