silly airhead question

Discussion in 'Airheads' started by R1100purist, Feb 14, 2011.

  1. R1100purist

    R1100purist Horizontally opposed twin dude

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    Hello, I have always been fascinated with airheads and after reading a couple build stories (Raven's in particular) I want to get my hands dirty. I found the following on craigslist,

    "1974 PART BIKE (r75/6) - ENGINE IN FRAME WITH FRONT FORKS, BRAKE AND REAR SWING ARM - NO TIRES OR RIMS, TANK, HEADLIGHT, REAR SHOCKS, OR CARBS - I HAVE THE PINK SLIP - MOTOR 13000 MILES WAS RUNNING WHEN DISASSEMBLED 3 MONTHS AGO."

    and I am seriously thinking about buying this and making a offroad/GS sort of custom job. My question however is as follows, will this frame/engine/FD accept the later GS (R80G/S, R80GS, R100GS, or otherwise) subframe, tank and other little bits and pieces in order to turn it into a bitsa GS? For an oilhead man such as myself it seems that not too much changed throughout the years. If this question is stupid and/or shows a lack of serious research also let me know. :ear
    #1
  2. Uncle Ernie

    Uncle Ernie Long timer

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    Partly, it depends on the money involved vs "practicality".
    How much has he offered you to haul it away?
    #2
  3. The Raven

    The Raven Banned

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    Um, Unless you have a good welder, machine shop, and about 2-3k it will be pretty difficult. The engine WAS running....there is a handful right there.

    Can it be done?...hell yeah

    Its dependent on your motivation. Did you know someone turned a K75 into a Paris Dakar bike and raced it?
    #3
  4. R1100purist

    R1100purist Horizontally opposed twin dude

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    Okay I am a senior in college and feel like I will need something like this to keep the continuity in my life after graduate. That said it would probably sit a while, before serious work got done. Having a project I can accumulate parts and work on over the years definitely appeals to me at this stage of life as a rebellion against the cheap and disposable consumer world around us.

    haha back to the point though, my goal is just to make this r75/6 more dirt worthy with perhaps new forks and certainly dirt appropriate wheel sizes. which hubs fit which year?
    #4
  5. spo123

    spo123 Man About Town

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    Do yourself a big favor........Get yourself a complete airhead that runs.......You will still spend much $$$$$ and effort.:norton
    OR DON'T.................................:deal
    Good luck with graduation!:freaky
    See 'ya.
    spo:freaky
    #5
  6. The Raven

    The Raven Banned

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    Hmmm, I've been out of college 10 years now. I was in your shoes though. I picked up a 73 Honda 450 and screwed with that thing everyday all winter while at school. Used my fin aid money to buy parts :D . In the end I had a hell of a bike that broke everythime I took it out until I got it sorted. I think if you have the time and ambition It's doable.

    To answer your question; All wheels will fit it if you know the right machinist.
    If you've been reading my thread early on Beemerguru and I went back and forth about the r80G/S wheels and the R100GS wheels and how you can use a G/S wheel on the GS forks as long as you have a the right axle.....you just need the right machinist to make it up.

    I have a suggestion though...instead of trying to make a dirt worthy R75, why don't you restore and sell it for the experience and buy a G/S or R100GS? Even an ST and GSify it, it would be cheaper and much easier as parts interchange much more than a R75. Just my .02
    #6
  7. Mista Vern

    Mista Vern Knows all - tells some.

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    What he said.
    #7
  8. R1100purist

    R1100purist Horizontally opposed twin dude

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    Thanks everyone! Sometime I just need to say things out loud to fully think through them. I guess I was in an ambitous mood when I came across this /6 and the possibilities of riding a bike I had built myself to Tierra del Fuego overcame me with youthful zest.

    I may see how low I can talk him down (currently at $650, if I can get him to $350, ill jump) and use it as a crash course in airhead restoration. Instead of getting crazy with a franken-bike however I would just get it back to be a R75/6.

    However, I will still look for a complete one, but have yet to come across one in my price range. The actual airhead GS's i have seen are usually the same price at my 25k mile r1100gs :huh
    #8
  9. dhr

    dhr Explorer of suburbs

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    I saw the photos of that bike or whats left of it. That looks like a heck of a project. I have learned despite my love of dirt cheap motorcycles sometimes its better to spend a little more. That being said if you can get the price down more go for it:D

    To put it in prescriptive. Right now in Nor Cal there is running R100GS with 41k for $2200. R80/7 with 71k for $1500. Also heard about a nice R100RT with 22k for $1400.
    #9
  10. Lornce

    Lornce Lost In Place

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    Read this again. And then again.

    I bought an R100GS a few years ago for $1500 and it was in better shape (far fewer miles) than my daily rider.

    Why reinvent the wheel?

    :dunno :scratch
    #10
  11. The Raven

    The Raven Banned

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    I traded my 95 r1100gs for an 06 KLR650....and was happier. The older GSes are better bikes than the 90s GSes. Same can be said for the BMW cars
    #11
  12. hensmen

    hensmen Been here awhile

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    Hey purist,
    we in the frosty south of germany would be lucky to get something like a
    rolling chassis for under 200 Euros.
    I think you could bild a bike and be proud to do it yourselve.
    Try to get this mag: Sonderheft BMW Motorräder, number 36.
    You find in it the pictures of Bill Kniegge, living next door.
    An other storie, but concerns your wish, Hubert Gudermann built two Sixdais-Replicas, i am not the guy in computer, can´t give you a link. But i found this
    "hugu60@gmx.de"
    The best source, i believe, is the "2-ventiler" Forum.
    Very nice people, fast, eager to practice english a a huge amount of airhead
    datas, download only as a member.
    Be welcome, Hans.[​IMG]

    Attached Files:

    #12
  13. Lokey

    Lokey redneck

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    I have been looking for a cheap airhead to convert into a dirt bike. My plans would only use the engine/transmission, swingarm and mainframe. The rest of the bike really wouldn't be used. That bike would be good for that sort of project as you basically would only be using the parts that are there and it has a title (unless the registration is way out of date). The bad part is that you don't know the condition of the engine. If you could get it for $350, I say go for it.
    #13
  14. Wirespokes

    Wirespokes Beemerholics Anonymous

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    For $350 I'd say go for it too. A good transmission alone is worth $250 or $300. Hopefully it's good.

    On that note, a GS may not be necessary for what you want. Guys have ridden around the world on old Triumphs, Harleys, and everything else. Frankly, I'd use the stock wheels (couple hundred bucks for the both of them), the twin shock rear end with a little longer shocks, and perhaps a newer front end of about the same length.

    There's a guy in Australia who rode just about every bike there is and found that the R65 was the best gravel backroads bike he'd ever ridden. With some dual sport tires it was the keeper. You can find one of those for about a thousand bucks (or less) in good running condition. Or you can just use the shorter R65 swingarm on that R75 you located.

    I think getting that pile of parts is a great way to get started. And if you're not in a hurry, and just take your time watching for parts it can be done quite cheaply.
    #14