Africa Twin Front end conversion / engineering

Discussion in 'Australia' started by atgreg, Jul 7, 2007.

  1. atgreg

    atgreg Africatwinarama Super Moderator

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    Another option;

    One of the few US guys with an AT has fitted earlyish USD CR Forks, he said it wasn't a big job, but he does run an engineering shop. Aparently the bottom bearing & stem is the same as the AT but the top of the stem and top bearing are bigger, he machined the top of the stem to fit the At bearing, runs a supermoto disc and had them valved & sprung to suit

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    #21
  2. OldDog

    OldDog aka Hugh Jarse

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    Curses you've seen straight through my cunning plan!:rofl
    #22
  3. Andrew2

    Andrew2 Team 250

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    Is there nothing that Pezz has'nt got dibs on:rofl
    #23
  4. atgreg

    atgreg Africatwinarama Super Moderator

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    Got an email back from a German "expert" on the Honda Dakar bikes, interesting



    Hi Greg,
    nice to hear from you.
    At the RD04 Marathon there is a regular AT fork with stronger springs and only one brakemounts on the left side,
    I think it is an RD03 fork with a transalp or RD03 wheel with 276mm brake disk (from Transalp PD06), Transalp brake shoe and 15mm axle diameter.
    the RD03 Marathom there is a stock fork with stock wheel and brake disk, only stronger fork springs.
    At the NXR are handmade forks from HRC, but also with 43mm diameter.


    So the Honda Dakar bikes used 43mm forks, Im surprised the works NXR's didn't use bigger forks even though it was the late 80's / early 90's. XR forks might not be to bad after all
    #24
  5. atgreg

    atgreg Africatwinarama Super Moderator

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    maybe this is what I need !!!!

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    #25
  6. atgreg

    atgreg Africatwinarama Super Moderator

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    Well the bits for my beast are coming together;

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    just waiting fo the tricky bearings that match the CR stemm to the AT steering head
    #26
  7. crash n bern

    crash n bern Long timer

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    One way to go about it would be to buy a secondhand or aftermarket set of tripple trees to suit a CR Honda, machine them to fit your bike, then machine them to fit the forks. Or you may be lucky and find they are the same diameter. Or cut your steering head off and weld on a new one to suit the ktm forks.
    #27
  8. JustAL

    JustAL Armchair Adventurer

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    Damnit Greg! Those shots of your forks give me wood!

    No wonder I work parts for a living!
    #28
  9. atgreg

    atgreg Africatwinarama Super Moderator

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    yeah, I was over at Pezz's yesterday and he was pretty excited to, we did some measuring and it looks like the CR forks wont be to hard to fit to the AT. I decided to go with the CR forks and Pezz has the WP extremes, he made me an offer I couldn't refuse.

    The forks and clamps I got on ebay for $US54 , :evil , $US100 postage but still just less than $AUS200 so heaps cheaper than from a wrecker here.
    #29
  10. Andrew2

    Andrew2 Team 250

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    Where can you buy the 640 copy front fairing from.
    #30
  11. atgreg

    atgreg Africatwinarama Super Moderator

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    Race motorcycles in Alice springs
    #31
  12. Andrew2

    Andrew2 Team 250

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    Thanks Greg.
    #32
  13. JustAL

    JustAL Armchair Adventurer

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    You can't tell me that shit! I'm suppposed to be saving for a whirlwind US tour and a concrete driveway!:rofl
    #33
  14. atgreg

    atgreg Africatwinarama Super Moderator

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    Operation CR Kayaba fork has started. A big thanks to Pezz and his neighbour for the machining, I owe you big time !!!:clap :freaky

    just to remind you, Im fitting up a 96 CR250 front end to my AT

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    The CR stem is 4mm bigger in diameter than the AT stem

    Original CR stem

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    Machined down to fit the AT bearings

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    Cutting the threads for the nuts

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    Done and the AT nuts fit, excellent

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    The stem will be pressed back into the triple clamps tomorrow, then Ive just got to wait till the forks come back from being revalved and sprung and we can bolt it onto the bike and sort out the steering stops and a plate to mount the ignition and sort out some sort of front mudguard.

    I'd really like to still have a low front guard, any ideas for a low guard to suit USD forks ??
    #34
  15. ozimick

    ozimick destination unknown

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    Kato 640 ADV front guard maybe ??
    #35
  16. atgreg

    atgreg Africatwinarama Super Moderator

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    Good thinking, must be a few lying around after high guard conversions
    #36
  17. atgreg

    atgreg Africatwinarama Super Moderator

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    Does anyone make a repo 640 or 950 front guard ??
    #37
  18. Dr AT

    Dr AT Long timer

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    . Do you want mine to see how it fits ? (pm me). Personally I'd steer away form the 640 guard - it's too short at the back and on the 640 you get stuff coming up under the chin of your lid. I guess on the AT you sit a fair bit further back so it might not be a problem.

    At least it would give you an excuse to paint the AT orange:evil
    #38
  19. atgreg

    atgreg Africatwinarama Super Moderator

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    Excellent, forks are ready to be picked up, stem is in the clamps, Im getting hold of a 640 Adventure low front guard to try and fit up to the showas, thanks Ozimick !!:clap , hopefully by new year it will all be together.

    Im a little concerned about the USD fork seals not lasting as long as Im used to, any thoughts ??.

    Has anyopne used the neoprene seal savers ??
    #39
  20. Dr AT

    Dr AT Long timer

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    I used seal savers on the 400 :cry that I sold to Jason:cry , before seal savers I got 2-3 months, after I got 6 years out of the seals. Have to say they seemed to help, although I did notice every 6 months the fork oil would go off with water in it. My suspension guy reckons they force water past the seals, but I reckon it's just that without them you replace the oil every 2-3 months when the old seals blow????

    you're still not going to get the 15 years honda seals last for, although they are honda forks so who knows?
    #40