R100R mystic cafe build

Discussion in 'Airheads' started by pommie john, Mar 28, 2019.

  1. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    I bought a load of boxes which are supposed to contain a 1992 R100R Mystic. It's missing forks, tank and seat, but most of the rest seems to be there.
    I'm thinking about a cafe/tracker bike. I'm getting too old for clip ons so the street tracker style appeals.

    I've done a youtube video and I'll be doing more as the build progresses.

    So far, I've fitted a set of GSXR forks after a false start with Hyosung GT650 froks which were rubbish, but their triple clamps fit the Suzuki forks quite well.
    47296395_10218240468345339_4324959817132146688_n.jpg

    I've got a nice seat from a Suzuki TR750 race bike and I was going to modify the subframe to fit it, but I think I might build a new subframe simply because the original Mystic subframe seems to be worth a few dollars on ebay.

    I'm not a professional bike builder so I'm sure I'll be making mistakes along the way and I won't be hiding them so others can learn from my errors :)

    #1
    bykpimp, Cogswell, BMW851 and 8 others like this.
  2. 2WheelTraveler

    2WheelTraveler backinthesaddleagain Supporter

    Joined:
    May 29, 2013
    Oddometer:
    578
    Location:
    Tahoe
    Looks like you're off to a good start.
    :lurk
    #2
  3. isheyesheis

    isheyesheis Adventurer

    Joined:
    May 21, 2010
    Oddometer:
    20
    Hi John,
    Great video, looking good already.
    I've a question about the Hyosung triple clamps, what is the offset of them, and the fork bore size for the top and bottom?
    Many thanks
    Stuart
    #3
  4. Boxerbreath

    Boxerbreath 2017.5 GS Black Storm

    Joined:
    Feb 7, 2018
    Oddometer:
    3,899
    Location:
    Lost Angels County
    Nice start. Did I hear you say 'street tracker'? What's a street tracker?
    #4
  5. Kiwiabbo

    Kiwiabbo Been here awhile

    Joined:
    Apr 16, 2014
    Oddometer:
    984
    Location:
    Taihape New Zealand
    It’s a good starting point with the late model boxer. Why not look to make a nice daily rider with it. Kinda like the mystic was but try an ditch some weight. Not exactly sure what a street tracker migh5 be but pretty sure it wouldn’t have a race seat on it. Do like that style of seat though.
    #5
  6. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    A street tracker is a street legal bike on the style of a flat tracker. There’s a thread in old’s Cool for photos of them.
    #6
    EngineerBill likes this.
  7. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia

    It will be suitable as a daily ride, and it certainly will be lighter than the original. I’m trying hard to source a suitable tank. One thing I don’t want is for it to look like a million other cafe racers that have the original big BMW tank.
    #7
  8. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    The Hyosung triple clamps are : lower 54mm, upper 51mm, offset 32mm ( as close as I can measure it) , and the distance between forks centres is 210mm ( again as close as I can measure.

    Edit: The Hyosung clamps have very big lock stops which are square lumps of alloy on the lower clamp. I had to cut them off as they hit the frame gussets. I'll have to drill the lower clamp and bolt some kind of lock stop on there.
    #8
  9. Boxerbreath

    Boxerbreath 2017.5 GS Black Storm

    Joined:
    Feb 7, 2018
    Oddometer:
    3,899
    Location:
    Lost Angels County
    Gotcha. Thought was a cafe bike but whadaiknow...
    #9
  10. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    It's a bit of both really. I'm making it up as I go along :)
    #10
    globalt38 and Pezz_gs like this.
  11. Kiwiabbo

    Kiwiabbo Been here awhile

    Joined:
    Apr 16, 2014
    Oddometer:
    984
    Location:
    Taihape New Zealand
    6158EF9E-2F31-4BDD-942B-73144A4BE546.jpeg ECFE33CC-A3B4-4C5A-9710-6F46B26C2E32.jpeg I used a mono tank, but then I also used a mono frame and modified it to take the paralever. The origonal frame was a little bent. Previous owner had a nice person pull out of a drive in front of him. Front wheel was an egg and the forks steering head all tucked in.
    #11
  12. isheyesheis

    isheyesheis Adventurer

    Joined:
    May 21, 2010
    Oddometer:
    20
    Thanks for that John, I've got a pair of 50mm W/P extremes for my G/S and i'm looking for suitable triple clamps (on a budget!) with a good amount of offset, they might be a contender with some shims :thumb
    Stuart
    #12
  13. MrBob

    MrBob Flammin the Diddle Supporter

    Joined:
    Oct 27, 2005
    Oddometer:
    21,462
    Location:
    Non-locational
    I'm looking for a speedometer for my 94 Mystic, in case you have one you aren't using.
    #13
  14. lemining

    lemining Adventurer Supporter

    Joined:
    Jan 29, 2019
    Oddometer:
    40
    Location:
    Sydney
    I'm looking for speedometer chrome cover if you are throwing your old one out.
    #14
  15. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    I’ll have a look in the boxes but I don’t think it came with a speedo. I’m away for the weekend. Gimme a day or two
    #15
    lemining likes this.
  16. MrBob

    MrBob Flammin the Diddle Supporter

    Joined:
    Oct 27, 2005
    Oddometer:
    21,462
    Location:
    Non-locational
    I'll keep you in mind.
    #16
    lemining likes this.
  17. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    Sorry guys, no speedo or tacho in the boxes.
    #17
    MrBob and Uke like this.
  18. pommie john

    pommie john Long timer

    Joined:
    Apr 9, 2008
    Oddometer:
    1,963
    Location:
    Brisvegas, Australia
    OK, the brake calipers are fitted. I got a pair of Brembos from a friend who's dismantling a 900 Monster. I made a plate from 6mm aluminium which spaces the calipers right in the middle of the discs, but then I wondered if 6mm aluminium is strong enough, so I took it to a local guy who has a water jet cutter. These plates cost $30 each made from stainless.
    I had to decide whether to use Suzuki calipers which would bolt straight on, but needed 320mm discs. That would mean having some discs made to order ( very expensive) or run the BMW discs and make a caliper arrangement to fit them ( much cheaper).

    The gold anodising on the calipers has faded and I'm trying to decide what colour to paint them. The original gold is hard to find in a heat resistant paint. IMG_5045.JPG IMG_5047.JPG
    All through this build, I'm open to comments and suggestions of better ways of doing this.
    #18
  19. Alfons

    Alfons Been here awhile

    Joined:
    Dec 23, 2007
    Oddometer:
    139
    Location:
    Germany
    Hello John,

    I am glued to the screen watching this thread develop.
    As regards the brake discs, I remember dimly seeing some Ducati 320mm disc fitted onto a BMW four-hole hub: This required drilling some new holes for the bolts, but apparently the inner diameter of the Ducati disc fitted onto the BMW hub.
    P.S. : I managed to find the picture:
    https://forum.2-ventiler.de/vbboard...Kreuzpeichenrad&highlight=Ducati+Bremsscheibe

    Best wishes from Germany

    Alfons
    #19
  20. Piggdekk

    Piggdekk love speed, hate rush

    Joined:
    Aug 14, 2015
    Oddometer:
    637
    Location:
    Barcelona
    I've built a few brackets for calipers but they never looked really good. Doesn't matter how they are done they will always look a bit ratty. I was ok with that, but it really comes down for the level of finish You are trying to achieve. My goal building custom bikes is always to get them on the road ASAP, and then refinish as needed, and in that respect your brackets will work.
    As fas as painting the calipers, the gold isn't paint but it's anodising. These Brmeobo calipers do polish pretty well if you got the time to do it, otherwise You can polish them less and then powder coat, maybe same color as the brackets so they are less evident.
    luca
    #20