'81 R100 questions from a new member

Discussion in 'Airheads' started by R100, Jan 29, 2013.

  1. R100

    R100 R100 UK

    Joined:
    Jan 28, 2013
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    19
    Location:
    UK
    Firstly hello everyone,

    I'm a long time rider and motorcycle wrencher from the UK. I've just bought my first BMW, a 1981 R100. She's in great, well ridden condition with an RS fairing retro-fitted.

    For now I have a couple of questions that I haven't been able to find the answers to.

    Firstly, as I've found is common, she has lost her center stand. Being a metal fabricator I was hoping to fab one up but wondered if anyone could give me some dimensions. Distance between the holes, overall height, the difference between the width top and bottom and the diameter of pipe used would be the most useful. I fancy I can make some improvements along the way too but If not I'll take the plunge and buy one.

    Secondly can anyone tell me is the older style dual seat (the chunkier one with chrome grab rail from the 70's /7 models) will fit in place of the standard 80's seat used on the R100 and RS/RT models without modification?

    Any help will be much appreciated. Thanks!
    #1
  2. disston

    disston ShadeTreeExpert

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    I think the seat with a chrome grab rail is a /6 item and that does not fit a /7 let alone an '81 bike. You might buy the grab rail and fit it to a seat that fits your bike? I don't really know about '81 seats. I think there are changes about that period. And with the RS fairing you have a seat with a cowling is appropriate?

    Plenty of used center stands around. Buy one. Once you find the center stand that fits you can measure it. There is an after market stand made by Reynolds called the Ride Off stand. Some of us really like those and you can usually find one but they aren't made any more. Maybe you could start a business of building Ride Off stands? We might buy a few.

    Welcome to the Asylum. You are now one of the Inmates.
    #2
  3. DaveBall

    DaveBall Long timer

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    The "mattress" style seat from any early /7 will fit. The mounting is pretty much the same. I took a "mattress" style seat off a 77 R100/7 and installed the cowl seat from an 82 R100. Fit just fine. So going the other way should be just as easy.

    As to a centre stand, it would be much easier for you to try and find one on EBay. But, you will have to remember that the 1981 year was a change over year for centre stands and only ones for 81 will fit. I know, as I tried both 1980 and 1982 stands, and could not get them to fit properly on my 81 R100RT. I eventually found a brand new stock stand on EBay that some guy had taken off when new as he had put on the Reynolds Ride-Off stand. I did the opposite, as I prefer the stock stand.
    #3
  4. Padmei

    Padmei enamoured

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    #4
  5. Mark Manley

    Mark Manley Long timer

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    If you can get hold of one the later centre stands off of the monolevers are a lot easier to use and fit straight onto the older bikes, I am thinking of the ones with splayed rather than parallel feet, see if you can try one before buying.
    #5
  6. 100RT

    100RT Long timer

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    I agree that the 81 was a unique year and the center stands were not designed properly. I have a Reynolds ride off on my 81 R100RT. You have to have the proper model number if you want to get a Reynolds stand.

    Yes the bench seat will fit on your bike BUT you can not use the seat fairing or the tool tray that is bolted on top of the rear fender.

    A friend of mine actually put the bench seat on his 82 RT and cut and fitted the back part of the seat fairing to make it look better. Being the crafty type he also built a set of spoked wheels for the RT along with many other custom touches.
    #6
  7. Paul_Rochdale

    Paul_Rochdale Been here awhile

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    Why bother? A new stand on eBay will cost you about £25 so not worth the bother IMO.
    #7
  8. R100

    R100 R100 UK

    Joined:
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    Thanks for the replies. Finding a reasonably priced stand is proving difficult. Motorworks here in the UK seem to supply the right one but want £125 for it which seems a little steep. Are there any other stands that are known to fit or can be modified? How about the R100GS stand which is available for a much more reasonable price?

    As for the seat, yes the one that's fitted is correct for the bike but is in a bad way and I've always liked the other style. Am I right in thinking that some R100s still had the older seat in '81? USA models perhaps? This advert from 1981 suggests so. The second pic is what I have fitted at present. Anyone shed any light on this?

    [​IMG]

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    #8
  9. Rapid Dog

    Rapid Dog bikes, booze, broads...

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    That's a Denfield saddle and yes it will fit your '81. They all have the same hinge system. Cowled dual, 3/4 solo RS, and dual with the grab rail will fit the frame/hinges.

    Check ebay.uk or www.motobins.co.uk/

    [​IMG]
    #9