airhead parts - the dark secrets revealed

Discussion in 'Airheads' started by datchew, Feb 24, 2007.

  1. wirewrkr

    wirewrkr the thread-killer

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    Luftmeister, Getting permission to copy something? :lol3:lol3:lol3:lol3:lol3:lol3
    Ask Craig Vetter about that sometime.
    Pack your lunch, you'll be there awhile.
  2. Lomax

    Lomax Nanu-Nanu Adventurer

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    i have been looking at ways to mount my Browns side stand and have just about come to the conclusion that if I want it on the bike, the exhaust is going to have to go back to stock. Not that there is anything wrong with that. :lol3

    Marc
  3. Beemerboff

    Beemerboff Long timer

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    Have a non stock stand on all my bikes - the Browns on my R75/7 is the least satisfactory.

    I have a right hand side 2 into 1 exhaust , so the Micky Mouse idea of clamping a structural support to the exhaust pipe was a non starter.

    Wasnt hard to rig up a bracket back to the frame but remember it turns the opposite way srom what you would think when it is loaded, that is the LH end goes up.

    My secong grouse is the light springand poor geometry on the stand - if I kick the stand down the frigging thing bounces back up again !

    The best stand I have seen is the one on my G/S made by a inmate here and sold on the vendors forum.

    The mounting plate for the stand is threaded for the engine mount bolt so the existing bolt is plenty long enough , and the front of the mount plate extends forward and is bolted to the pivot bolt for the G/S footrest, secure and safe.
    The spring geometry and strength are better than the Brown too - clunks solidly down and up , with no hint of a bounce.
  4. brentde3

    brentde3 Should be outside

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    Anybody know where one might find a replacement cylinder base o-ring for a 1976 R90/6 without resorting to ordering from a parts place? How about the cylinder stud o-rings? (I assume those are easier to find at an auto-parts joint.)

    I've got NAPA and Advance Auto and various other hardware and auto-parts houses around. The nearest Beemer dealer is a four-hour round trip and I really don't want to wait for the UPS guy.

    Thanks!
  5. wirewrkr

    wirewrkr the thread-killer

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    There is no cylinder base Oring on a 76.
    If you've got one PLEASE shoot a pic and share!
    BMW used just the stud Orings until mid to late 80, when they introed the base orings.
  6. airheadpilot

    airheadpilot Le Poulet du D├ęsert

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    There was, however, a base gasket on the older bikes. The base gasket was replaced by the base o-ring from 1981-on.

    Andrew
  7. wirewrkr

    wirewrkr the thread-killer

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    Not true.
    The standard 76 to 80 models did not use a base gasket either.
    There was one available from BMW to lower compression when pinging occurred. But not from the factory. Basically cylinder was glued directly to the case.
  8. Jim K in PA

    Jim K in PA Long timer

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    My '79 R100T with a build date of 12/78 has cylinder base o-rings. FWIW.
  9. wirewrkr

    wirewrkr the thread-killer

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    Interesting. My 80 R100T shortblock does not have the cutout for the orings. It has build date of 11/79
    Here a couple of shot of what they are supposed to look like.
    This first pic is a 93 GS block.

    Attached Files:

  10. wirewrkr

    wirewrkr the thread-killer

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    1980 R100T Block, build date 11/79

    Attached Files:

  11. bmwrench

    bmwrench Long timer

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    '79 and '80 used the cylinder base o-rings without a relief in the case-these were the 2.0mm white o-rings which now seem unavailable.
  12. wirewrkr

    wirewrkr the thread-killer

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    thanks Bud.
    Mystery solved
  13. Jim K in PA

    Jim K in PA Long timer

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    Interesting. BTW - I ordered a set of O-rings from Jeff Trapp at Northwoods Airheads back in April or so and they were readily available then.
  14. wirewrkr

    wirewrkr the thread-killer

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    The smaller size went nla from BMW many years ago, but obviously Jeff is sourcing them from elsewhere if they are the smaller of the two.
    They used to list two sizes, does Jeff?
  15. Jim K in PA

    Jim K in PA Long timer

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    I don't see more than one size, but I did not ask Jeff when I ordered what size I was even getting! Ignorance was bliss in that instance. Here is the page with his o-rings: http://www.northwoodsairheads.com/maintenance-parts.html

    I can say that the o-rings looked like the same size as the white ones I took off, and they worked fine and are not leaking after 500 miles or so.
  16. wirewrkr

    wirewrkr the thread-killer

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    I guess I don't understand why one would buy parts from a non BMW source when the prices are pretty much the same. That's just me though.
    Oh and as I've seen with lots of other venders just starting out in the parts business, There are more than one application mistakes in his listings.
    I like Jeff Trapp, he's a good guy, but the mistakes need to be rectified so people don't buy the wrong stuff. That makes for upset customers.
  17. ozmoses

    ozmoses Ride On

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    So, if these are NLA what is the appropriate substitute? Sealant w/out an o-ring?
  18. Beemerboff

    Beemerboff Long timer

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    Some folks like 3 Bond sealant, instructions are on the pack - it is still sealing after 10 years on my 75/7.
  19. Fudmucker

    Fudmucker ex-lurker

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    Has anybody found an alternative source for this?

    BMW Part number 31421241649 - 'guide ring'

    There is one in virtually every Airhead front fork damper since 1980 and they cost US$21.76 each!
    Due to Regional pricing were I live, they cost the equivalent of $37.50 apiece.

    I haven't actually weighed one, but I suspect this tiny teflon trifle of a part is more costly than its equivalent weight in pure gold!

    Attached Files:

  20. Boxer Metal

    Boxer Metal Mad Scientist

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    Expensive little part. I would think someone could make this part for under $10.00.