1972 r75/5

Discussion in 'Airheads' started by assquatch20, Sep 20, 2012.

  1. disston

    disston ShadeTreeExpert

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    There are several places water gets in Airheads. the most famous is the speedo cable boot on the transmission. Water can also get in the carbs but I don't know how it gets in there. Running down the intake tubes maybe. I found water in my final drive last year, still don't know how it got in there. If there's water in the gas it separates during storage and rusts the bottom of the gas tanks. Rusts them right at the seem along the bottom.

    The timing window is for looking at the edge of the flywheel for finding TDC and ignition timing. This area is open to the out side on the bottom. It's not sealed. Not very likely water would do much damage except rusting the clutch to the flywheel and the pressure plates. Have you worked the clutch to see that it works yet? I know you have started the engine. If the flywheel is rusted to the clutch you will think there is no clutch. If you can push start the bike in second gear and try revving the engine and trying to shock the parts apart. Try revving the engine with the lever pulled in. Sounds worse than it is. It is the standard way to unstick a clutch that's rusted to a flywheel for any machine, not just Airheads. And surprisingly they usually do survive if the clutch wasn't worn out to begin with.

    Seat latches and seat locks are often in disrepair. Look at a parts fisch and you might get an idea of the complication. Mines been messed up for years. I need a complete usable latch to start with I think but I make do with what I got because it still works, sort of.
    #41
  2. Renner

    Renner combustophile

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    not necessarily.
    these things tend to evolve with time.

    SWB or LWBwheelbase?

    for instance, a lwb would have had an extension welded on the business end of a swb swingarm till BMW ran out of swb swingarms to modify.
    Once the parts supply caught up with the drawing change, the extension would no longer have the appearance of an afterthought.
    #42
  3. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    Not true. My /6's all have the weld.

    Just look to see if there's about 2 inches of "wide", weld or not.

    [​IMG]
    #43
  4. assquatch20

    assquatch20 Hoss Cat

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    Clutch seems to be working pretty well. What I could see of the flywheel looks clean too. The weird routing for the cable is a trip.

    Wouldn't there be more battery room if it were LWB though? The guy got a bigger battery and had to ziptie the tray to its mounting points. What are the chances it's just a /6 seat cover? Or the seat is just slapped on there, explaining the non-latching and wobbliness of it?

    In any case, we'll get down to the bottom of it soon, Scoob.

    Edit: I also want to thank you guys for pitching in advice and hypothesizing with me. You don't have to do it, but it puts someone else that much farther when you do.
    #44
  5. Renner

    Renner combustophile

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    sez the dude with the '74s :rolleyes


    :D
    of course there are exceptions...
    #45
  6. wirewrkr

    wirewrkr the thread-killer

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    My brothers 1975 /6 has the add-on weld, and we know for a fact that the bike is original. build date of 11/74
    I don't remember if my 76 had it.
    #46
  7. subagon

    subagon Hopelessly lost

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    My '75 R90/6 (known original bike), with a 10/74 production date, also has the weld and aluminum turn signals. Just because it was a new model year, BMW didn't throw away good usable parts.
    #47
  8. Renner

    Renner combustophile

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    alright
    alright
    alright:

    fixt

    :doh

    quite right
    #48
  9. wirewrkr

    wirewrkr the thread-killer

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    Once again a case of someone bothering to take on the laborious task of creating an actual webpage with his opinions that are taken as facts, and well they're just opinions after all, but hey, "I read it on the internet, it must be true!"
    :lol3
    #49
  10. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    It's at least a good foundation to build on and there is a lot of information there.. so you can't hate too much. But it would be refreshing if people didn't state their opinions as facts - that just confuses the n00bs!
    #50
  11. wirewrkr

    wirewrkr the thread-killer

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    who said anything about "hating"?
    Does disagreeing with something and pointing out important negative aspects (so that others can get a more realistic way to determine actual reality ) count as "hating"?
    Gosh I hope not.
    If there's one word in todays modern vernacular that is being overused and misused, IN MY OPINION, it is that one
    #51
  12. Renner

    Renner combustophile

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    guys
    I'm fallible and I know it.

    It's obvious to most (I believe) that the internet is not the fount of all knowledge.
    I usually try to couch my posts with sufficient qualifying statements.

    My apologies for being sloppy and passing along misinformation.

    As you may know, my good intent was to respond to assquatch20's statement:
    which hadn't yet been addressed.

    There's plenty to learn, some of which we learn to un-learn.
    #52
  13. assquatch20

    assquatch20 Hoss Cat

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    I think this is one of the few times I've had a thread derail. I'm honored. I guess you have to have good subject matter to begin with.
    #53
  14. wirewrkr

    wirewrkr the thread-killer

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    My Bad, I admit it. I was driving that train when it derailed. Must be related to Casey Jones
    #54
  15. assquatch20

    assquatch20 Hoss Cat

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    Oh, I don't really mind. I'm learning from it, and it helps keep the thread alive. I'll return the favor this weekend with some pics of what I'm working with. Also, I was looking at your site. Can you do a complete set of harnesses for a /5?

    And for a general question, I mentioned earlier how the fairing had a pressure gauge and a volt meter that seemed to work. Should I expect a tapped hole somewhere for the gauge?
    #55
  16. wirewrkr

    wirewrkr the thread-killer

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    I don't bother with the /5 Main harness as BMW still has a bunch in stock, and they are CHEAP!
    Buy one now before they go way up like everything else from them.
    #56
  17. blaine.hale

    blaine.hale Long timer

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    Yup. I had just ONE clipped wire on the one that came with my bike...that was enough for me to spend $65 on a new harness :)
    Speaking of which, I have a spare harness if anyone needs it!
    #57
  18. kc0yef

    kc0yef not new to *****s

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    If you are against the established norms it is not a hate crime but a thought crime
    Thanks everyone for all the information here I am enjoying the text

    #58
  19. assquatch20

    assquatch20 Hoss Cat

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    [​IMG]

    More to come tomorrow I think, maybe even with a proper camera. Won't idle much and stumbles, but I made it 20 miles home on the thing. Buffeting over the fairing was trying to tear my helmet apart, but effortless movement at 65 for awhile.

    Anyhow, I had to leave as soon as I got it home, so we'll dig in tomorrow + a 4 day weekend starts Saturday.
    #59
  20. pfestus1

    pfestus1 Slasher

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    Well, I haven't been paying attention to this thread. Lots of good advice, and info.
    I agree with starting slow. Just do enough to get it it going and running well.
    Someone pointed out how to remove the Wixom saddle bags. Also usually the right side bag frame is designed so the upper mounts have pins that you pull out, then pull the mount out and let it drop down out of the way. This allows the seat to hinge up. On mine, I removed the hinges f rom the seat and just lift it off. The lock pin holds it in place fine.

    ASAP get some PB Blaster or other good penitration oil and spray all the screws and bolts that you may be removing. Like the carb top screws (be very carefull with these, may need to use an impact driver to break them loose), the seat hinge screws (allen head), muffler bolts, and clamps, finned muffler nuts that hold the pipes to the head, etc....

    I really believe that my SWB toaster tank with a fall of '71 build date has the recess for the later disc brake parts. I"ll pull it off and look again. The build date should be stamped on the info plate on the steering head.

    Here is some inspiration for you. This bike had sat for 20 years in an open shed. It was a mess.

    [​IMG]

    Link to my Barn Queen rebuild:
    http://pfestus1.smugmug.com/Motorcycles/Rescue-Beemers/2946565_WfM5g9#!i=159107063&k=jb6Ws
    #60