'81 R100RS turned cafe

Discussion in 'Airheads' started by theDQG, Oct 1, 2017.

  1. Marine72

    Marine72 Adventurer

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    Welcome Arthur and don't let some of the inmates get you down. They may bust your chops but all in all a great bunch with a wealth of information. I'm doing a similar build and received the same flak but when I pose a question or ask for advice they will jump in and provide all the support they can. It is possible to achieve the look you want without chopping anything. Good luck and have fun with your build. I look forward to seeing what you come up with.
    #21
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  2. theDQG

    theDQG Adventurer

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    Thanks, I appreciate the support. I'm in the process of stripping down the bike and shipping the engine off to someone to overhaul. Do you have a thread of your build?
    #22
  3. Marine72

    Marine72 Adventurer

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    I do : 84 r100 my way
    You will see I got blasted just like you and probably more. All be it my initial concept was quite different. That changed not because of the inmates but personal choice of a more classic look. I can fab a new bolt on shorter subframe to achieve the look I want while keeping shock mounts close to original. Mine is mechanically sound so the only work I have is cosmetic and new electronics. Mock it up, test ride, then tear down for paint. It is hard, but be patient. I want mine done yesterday but at times I have to step back, think on it and do more research. If you get stumped put it in a thread. I’ve gotten a wealth of info and ideas from these guys.

    RJ
    #23
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  4. Kiwiabbo

    Kiwiabbo Adventurer

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    Your bike and your ideas. My only comments would be what do you want out of it at the end of the day. I’m with one of the others on here. Make it rideable. They need fenders to sto both you and the bike getting covered in crap. Have fun. Look at a lot of pictures and ask heaps of questions. I started with a wreaked bike and then bought reclaimed parts to make the bike. It was a project with my father. He’s the clever bugger.
    The good thing about BMW is a lot of parts can be shared between models with no or limited modifications. This one is a real mix of bmw models. 0BF82AF6-98B4-45D6-B4B5-320A5343B3FA.jpeg
    #24
  5. theDQG

    theDQG Adventurer

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    Thanks for sharing.. very simple concept, how did you hide the wiring? Is that a fabbed rear seat subframe?
    #25
  6. Kiwiabbo

    Kiwiabbo Adventurer

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    The subframe is basically a modified mono sub frame as is the mainframe. it was shortened, added braces and the battery box was biffed up under the cowling. The seat is a shortened s seat with different mounts. The wiring has just had all redundant stuff removed and clipped up as per usual along main frame and sub frame. Dads latest photo photos 136.jpg
    #26
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  7. Kiwiabbo

    Kiwiabbo Adventurer

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    That was our basic concept at the start. get what we wanted and get it together in a rough form. Ride it and make any other changes.
    1 the concept.jpg
    #27
  8. shovelstrokeed

    shovelstrokeed Long timer

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    The makings of a fine bike with cafe looks can be had right from the BMW parts books. They were called the R100CS. No need to chop anything up.
    #28
  9. nmalozzi

    nmalozzi airheaded

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    There’s a difference between “cafe looks” and a “cafe bike”. Cafe bikes are minimal and stripped down to bare essentials. Something a CS is not, or any other factory bike. In fact there’s really no such thing as a “factory cafe bike.” Which I know you didn’t explicitly say, but that phrase is an oxy moron none the less.
    #29
  10. Kiwiabbo

    Kiwiabbo Adventurer

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    So basically have one of those too....in a away 161B1115-5ABA-40D9-A867-367C6411BEF7.jpeg
    #30
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  11. shovelstrokeed

    shovelstrokeed Long timer

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    I know, Nick, I've been around a little longer than most. When executed by a craftsman with an eye for balance and utility, they can be both pleasing to the eye and functional. When hacked apart by some schmuck with an angle grinder, they serve neither purpose.
    Those R90S bikes were the design inspiration for the R100CS
    #31
  12. nmalozzi

    nmalozzi airheaded

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    I fully understand and appreciate the relationship between the r90S an the r100CS. In fact I’d happily accept either into my garage. I also agree that a schmuck with an angle grinder can ruin a bike, but that’s not exclusive to BMWs or Cafe bikes. The point I was trying to make is that an S or CS is not a Cafe Bike. I feel they are factory sport touring bikes. However, I’m not here to argue what they are. I’m here to argue what they aren’t, and they certainly are not cafe bikes.
    #32
  13. BMW851

    BMW851 Piston Broke

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    shovelstrokeed, I think that may read and be a little more model correct in saying the R90S became the R100S in '77 or there abouts, which in turn became the R100CS in '81 or so, having owned both of the latter models, fairly sure I can get away with saying that.

    As to hacking up a perfectly good RS, not keen on the idea at all, but it's your bike to do what you want with and tell us all to bugger off, but as others have suggested, I'd keep the fairing and other parts, and try and do it in a way that that allows for it to be returned to original, it will be a good selling point when that time comes, an "can be easily returned to original with all original parts available" statement will attract a much wider range of buyers.

    And here's a hint, I was planning to do an S style conversion on my pristine '88 R100RS Monoshock and graft on a 1st model RS 3/4 seat, but circumstances changed and the bike was sold before that happened, if they hadn't, well a Pearl White S would have been fairly purdy motorbike.
    #33
  14. bmwloco

    bmwloco Long timer

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    Been on BMWs for damn near 40 years now.

    Cafe bike and BMW have never occurred in the same sentence - only in the last decade.

    It makes me laugh. Any idiot knows that Cafe bikes are built Triumphs or Ducati... BMWs are never fast, just go far.
    #34
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  15. shovelstrokeed

    shovelstrokeed Long timer

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    There are cafe bikes and the modern interpretation of the cafe bike. Yes, there is a difference. The original cafe bikes were built to do the ton from one cafe to another or a round trip to the same cafe. Doing the ton had a different meaning back then, it was to average 100 mph for the trip, not just to reach 100 mph which was pretty much a difficult task back in the 50s and early 60s. The bikes were stripped to the bone to gain a bit of acceleration which had very little to do with gaining top speed. They found out about aerodynamics later and started imitating the road race bikes of the day.
    Here in modern days, the same ignorance of aerodynamics holds sway and bikes with all their naughty bits hanging out and missing or chopped fenders are classified as "cafe" bikes. They are more properly called bobbers but even that term has been ruined by the no fender, minuscule seat and straight pipe crowd.
    One trip through Craigslist Shitheads will prove my point.
    #35
  16. theDQG

    theDQG Adventurer

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    In keeping with the goal of modifying the frame as little as I can, I have been looking for a subframe that will take a cafe seat that requires no alternation but simply bolts on. So far I have found 2 or 3 excellent candidates but they are all in the UK. Are there any outfits in the US that makes something like that? Thanks in advance.
    #36
  17. Marine72

    Marine72 Adventurer

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    I found all the UK options when I began my search as well. I found that they were either way to expensive or the design was not what I was looking for. How handy are you at fabrication? I decided to build my own bolt on to fit my seat. It takes time but in the end no one will have one like it. I can incorporate a new battery location and a tray for the motogadget blue and wiring. I’ve just started mine. I bought an extra long frame hoop from eBay and bent it to follow the line of my seat and meet up to the front mount location. I still need to fabricate front mount tabs to weld on the modified hoop. Bottom mount tabs are finished. Once front mounts are completed and bolted to the frame I can fit the down tubes and weld to bottom mount tabs.

    446C0945-8953-4E62-A56B-E1123CF84774.jpeg
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    8575E55B-42A1-44FD-B73E-416C48EA5C4C.jpeg
    #37
  18. eight90eight

    eight90eight Long timer

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    So how do riders tolerate the seats on these cafed bikes? And if they can be ridden for only a couple hundred miles, what's the point? I keep thinking, "OMG, my aching back, wrists, neck." My old S type retains the good ergo adjusted to me over the many years and can go through several tanks, all day long, turn key hot rod with tent, tools, spares.

    As for going a hunnerd miles an hour, it would take a hellova Brit bike to accomplish that feat back in the day, if you could hang on with numb hands, maybe with an uncalibrated speedo. FWIW, IMHO.
    #38
  19. nmalozzi

    nmalozzi airheaded

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    One doesn’t build a cafe bike and go tour with it. That’s not the point.
    #39
  20. Kiwiabbo

    Kiwiabbo Adventurer

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    And yet I’ve done a few weekend rides with over 800k weekends on mine. You get used to it and you have a few “cafe” breaks along the way. The old man took his 1200gs so room for gear for both of us in the panniers. All good fun
    #40