New purchase R100/7 1978

Discussion in 'Airheads' started by slepsnys, May 31, 2012.

  1. slepsnys

    slepsnys Adventurer

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    #1
  2. Beater

    Beater The Bavarian Butcher

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    Not bad. My first BMW was also a 78 R100. Good to learn on ... and if you are not mechanically inclined ... get ready, you're about to be. Once they are running good, there's no stopping them ... but it can be a bit of a learning curve. Go into it with a open mind, and heart. Know that it will probably take at least another $1,000 to get it running (Rusted tank ~$200, New switch ~$120, Seat - $250, or recovered for $100 ... and the random parts ... $$$).

    Congrats on the bike, learn to post pics, and let humility be your friend. The people here are amazing with diagnosis ... if they have all the information. My '78 R100 I bought for $800 ... I've probably put ~$2,500 in it ... and countless hours. It's been great fun, and a huge learning experience.

    Good luck!!!!
    #2
  3. LotaBikes

    LotaBikes Adventurer

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    Was the PO trying to make it a cafe bike? One good thing is the dual disc front brakes, The valve covers are earlier than '78 but look better than the '78 ones. Have fun!
    #3
  4. ozmoses

    ozmoses Ride On

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    Nuthin' but a headache, better pass it on to someone who won't mind. :evil

    I'll echo Beater's sentiments, 'cept mine was a '77.

    Have fun!
    #4
  5. sithndman

    sithndman Been here awhile

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    My only is a 78 R80/7. Wonderful machine that you will WANT to learn about! I'm having a blast with mine Ann I'm sure you will too!
    Like Beater said, this is a wonderful resource, enjoy using it.
    #5
  6. groop

    groop So much to ponder

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    Congratulations on your purchase. I bought my first airhead just last month and have found a ton of excellent advise on this forum, the BMWMOA forum and elsewhere.
    #6
  7. Wirespokes

    Wirespokes Beemerholics Anonymous

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    Welcome to the fold...er, asylum. Yeah, that's what it is! Nobody here but us crazies.

    It is possible to turn it into a good rider fairly cheaply, but that requires rebuilding things yourself and knowing where to find good used bits. If you want to go the high dime route, that's ok too.

    Hope it doesn't need anything major!
    #7
  8. slepsnys

    slepsnys Adventurer

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    Yes, I am also hoping that there is nothing more serious than, broken kill switch. Also what do You think about changing points ignition system to later electronic ignition with original BMW parts? :)
    #8
  9. bikerfish

    bikerfish flyfishandride

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    I'd just keep those original points, something that can be fixed/replaced by the side of the road if needed. I've had many many airheads, I've had problems with everyone of them that had electronic ignition(ign trigger unit failure), never had a problem with any of the bikes with points.
    besides, I never felt any improvement in performance from the bikes with electronic ignition. I mean, if you want horsepower, buy something else.
    #9
  10. slepsnys

    slepsnys Adventurer

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    I am planing to rebuild carbs and want to order gasket kit, maybe somebody could tell from the photos what Bings does it have, how much mm.? :-)
    #10
  11. disston

    disston ShadeTreeExpert

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    When you get to rebuilding the carbs start with the Kit, That's O-rings, gaskets and diaphragms. Likely you will need a few more things too. We'll cover that after you get it running.

    Most likely the kill switch does work it just doesn't click but check to see if the wire to the coils on the left side of the bike is hot with key on to check. There's probably someway you can wire the switch out if needed. It would be best to start accruing the tools and books you are going to need. A manual will have the wiring diagram in it. This will save so much time over having other inmates try to tell you which wire goes where on your bike. You'd be surprised the number of noobs that think they can do wiring with out a wiring diagram.

    There's a good chance that either your new bike needs a new set of ignition points or the rust from the tank has clogged the petcocks and the carbs don't have any gas. Start with cleaning the tank, replace the fuel lines, clean the float bowls and see that fuel is flowing. Next check that the coils have power, left side terminal. And tell us if this gets her started.

    Oh, since she hasn't run in a while I like to change the oil right away even tho I can't get the old oil hot. I change the oil and filter and will change the oil again after she's run just a few miles. For this first oil change, break in oil if you like, you can use cheaper 10-40 oil. After that it's 20-50 all year.
    #11
  12. disston

    disston ShadeTreeExpert

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    The carbs look like the correct thing. Numbers on the side of carbs should be 64/32/19 & 20. 19 will be on one side the other side will be 20. Tell us what numbers you have on those carbs. The number is on the plate on the side. You can't miss it. These a 32 mm carbs.

    Do not start off with changing the ignition system. First get it running. Put some miles on her and see what she needs. There are things on that bike with a lot of miles and some of them are going to need attention before you get around to making the ignition modern. It's not done usually with later model BMW parts anyway. It's done with after market parts.

    Tell us how many tools and what kind of tools are with the bike when you get it. The tool tray is under the seat.

    Also tell us what kind of experience you have with gasoline engines, older cars maybe?

    She looks like 121,000 miles and lived most of her life outside.
    #12
  13. slepsnys

    slepsnys Adventurer

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    Thank You very much disston for a lot of important information and detail explanation :)

    Well, talking about my experience with engines and cars, I have never had gasoline car, now I have Alfa Romeo 156 2.4 JTD diesel car and I repair it myself, including regular maintenance also changing belts generator, timing belt, glow plugs, oil, repairing suspension and so on... Alfas likes to break :D

    I can't look to the numbers of the carbs, because I still don't have the bike in my hands, it will arrive on 19 this month.

    And how about the mileage of the bike, 121,000 is very much or normal to ride it with without problems in the future not fearing that it can break anytime?
    #13
  14. disston

    disston ShadeTreeExpert

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    Over a grand on an Airhead is OK. Mine has over two grand I think. But if this is the case there may be some major component rebuilding in your future. Not to worry. Anything can be fixed. A friend of mine had a sign in his shop, it said, "Cheap, good or fast. Pick any two."

    Do you know if you are getting any manuals or tools? Especially the manual you might go ahead and pick one of those up. But just in case there might be a manual then wait till it arrives. You don't need two manuals. Or at least not two of the same one.
    #14
  15. slepsnys

    slepsnys Adventurer

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    I don't know if it comes with any tools or not, but I am 99% sure that it will not have manual, so I need to get one, which manual You would recommend Clymers, Haynes or something other? And maybe there a possibility to download it from somewhere?
    #15
  16. Harry Backer

    Harry Backer Ran when parked!

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    I use the Clymers some folks have both. Great bike I love mine. Lots of info on this forum.
    #16
  17. disston

    disston ShadeTreeExpert

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    You will do best to accept the fact up front these manuals are not available for free on the internet. That is probably related to the fact that they are still in print and still copy righted.

    I'll say either one because I have both. I sometimes hear more criticism about the Clymers I think but I don't really see that much a problem with it. There are mis-prints in all the manuals is the main problem I think. In Clymers I've found a couple of places in the dialog where I didn't like how they said something but it usually comes down to you should know what you are doing anyway.

    You might find either one of these used on Ebay but the dealers overwhelm most searches to find the used stuff because they want you to buy new. They are not cheap either.

    As much as we can complain about Clymer's manuals they are better reading I think.

    I also have the BMW /6 shop manual. It is recommended but expensive. It's not really for everybody. But the info is right on. It's the most boring of all three to read but whadaya expect, it comes from the Father Land.
    #17