'82 centerstand, what's the deal?

Discussion in 'Airheads' started by Bluethumb, Feb 8, 2013.

  1. chasbmw

    chasbmw Long timer

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    My 75 has 2 cross pieces and is a delight to use. The stand on my 82 is a recent replacement (3 years ago) , it's ok on a bare bike and better than the original stand.

    So did Bmw revise the design of the 81-84 stand. They did so with the side stand.
    #41
  2. Rob Farmer

    Rob Farmer Long timer

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    My 78 100/7 has two crosspieces and as yours is very easy to use.

    I've recently bought an 81 that has a stand with a single crosspiece, a checked plate on the left hand foot of the stand for pressing it down with and a folded steel tang for dropping the stand down. I have an 83 R80TIC with a single crosspiece, no chequered plate and a straight steel bar coming out of the side for dropping the stand, very similar to Blues stand in your photograph but without the bend in the side bar.

    The 81 also has shorter springs than the later stand.

    Be nice to get to the bottom of this. I suspect that many of the 81/early 82 machines are fitted with the wrong stands.
    #42
  3. ME 109

    ME 109 Long timer

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    Oh no! That puts my bike right on the epicentre :huh
    (September 81 build)

    If the stand mounting bracket (welded to the frame) is the same, and in the same position on bikes of the surrounding year or so, it can only come down to how long the stand is? Which would come down to how high the front wheel comes off the ground when the bike is on the c/stand?
    On a level surface, my front wheel is about 70mm off the ground.
    #43
  4. boxerboy81

    boxerboy81 Stay Horizontal

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    This centre stand fits my 11/1981 R100RS. Single crosspiece.
    [​IMG]

    It's essentially identical to the one I have on the bike.

    However, modifications have made them different, but it's minor.

    This is the one I have on the bike. Notice the extra bits added to the ground contact area. The foot lowering tang is modified..beefier and more curved to the underside of the exhaust.
    [​IMG]

    The spare is essentially unused, but I suspect it was removed from its original home when the tang snapped. The repair is a little rough.
    [​IMG]

    Hey Jeff, would a little anti-rust paint control that corrosion?
    #44
  5. caponerd

    caponerd Kickstart Enthusiast

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    Bump.
    Too bad the pictures linked above are no longer available.

    I finally decided to deal with the centerstand on my '82 R100.

    I did the welding job on the tops of the legs on mine.

    I wonder about those bushings. Mine were installed with the flanged ends out. Some of the pictures I've seen also show them that way.
    Seems like the wider surface on those ought to bear against the frame.
    Anyone know for sure?

    The bushings on my bike were worn, one way more than the other. It has a spiral groove in it from that side of the stand shifting outward as the stand is deployed.
    Why are the bushings so much longer than they need to be?
    I decided to make up some shims to put on the bushings to fill the extra space.
    With the bike supported so the centerstand can be removed or manipulated easily, I measured the amount of bushing that protudes beyond the tops of the stand legs and made brass washers that are just shy of that thickness.
    After installing them, I found that once the stand is deployed and the weight of the bike is applied, the top of the stand springs outward and applies so much pressure outward that the whole aasembly is stuck together to the point where the whole thing, bolts and all rotates with the stand. Once the stand is folded up, the wahers I made loosen up.
    I had to cut them down to half the original thickness before they would renain free with the stand deployed.
    This wasn't a problem if the bike was raised up on a stand so that no weight was place on the stand.
    I've currently got my centerstand working the way it should, but I'm curious to know if anyone else has noticed this weird phenomenon?
    #45
  6. Prutser

    Prutser Long timer

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    Could be that someone used the bushings from the reinforcement kit BMW used to sell for those bikes.
    They had a kit with longer bushings including a plate that needed to be welded on the outside of the frame.
    That way the frame taps wouldn't bend anymore. The bending of those frame taps is a big reason of those stands going bad.
    If the taps are bend the distance between the pivot points and the stops become bigger. Thats why most of them sink to deep when they are on the center stand.

    I have repaired at least 50 of them using the reinforcement kit. Then they won't breake anymore and even those models are easy to get on and off the stand.

    Nr.19 was the reinforcement kit.

    [​IMG]
    #46
  7. ME 109

    ME 109 Long timer

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    That reinforcement kit is interesting Pruster, did it solve the problem of the worn contact area on the stand, or did that need building up with weld and reshaping?
    #47
  8. Prutser

    Prutser Long timer

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    That depended on how long the owner would wait before they came to the workshop to have it repaired.
    Some needed the welding others didn't.
    Most of the time the frame tabs were bend.
    I don't have pictures because I used to fix those thing 20 years ago.
    #48
  9. ME 109

    ME 109 Long timer

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    Last I saw the frame tabs on my 81 I thought they were in good condition and showed no real wear at the point the c/stand contacts in deployed position.
    Maybe these tabs/mounts changed through the 70's and 80's ?






    First thing I noticed when I fixed my c/stand was how poorly the c/stand utilised the available contact area of the frame tabs. That is why I increased the width of the c/stand with weld.

    My stand repair was maybe 5 years ago and has endured a shitload of ride offs when fully loaded for touring.
    The front wheel up in the air suggests little wear of the repair.
    Many times it's a matter of assume the riding position with feet on pegs, hit the button and ride off the stand and away!

    When these c/stands are worn and the bike goes way back too far, they are ridiculously difficult to get back off the stand.
    Achieving the desired deployed angle of the c/stand is what the weld repair aims to achieve. The ideal angle is not a long way from 'rolling off the stand too easy' .........or don't put it on the c/stand facing downhill. :wink:
    The welded and shaped repair to the c/stand has to contact both frame mounts simultaneously. This is achieved by shaping and trial fitting until it's correct.
    Anything less than equal contact will wear one side away until they are equal.

    Easier said than done.
    #49