Leading link fork setup help

Discussion in 'Hacks' started by drrags, Jul 20, 2008.

  1. drrags

    drrags Dorkus Malorkus

    Joined:
    Jan 23, 2007
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    1,886
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    I drove a Ural Patrol yesterday (bad Arno!) and besides being impressed with the whole rig, I was most impressed with how easy it steered. That lead me to study my front end and start wondering if it is set up properly. I've searched all over the place for any hints on leading link fork setup, but have only found general descriptions of rake and trail but nothing more solid. Can anyone point me to something with a little more meat on it regarding fork setup that uses real numbers? :deal

    Mine is an older Unit front end.

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    #1
  2. tony the tiger

    tony the tiger Long timer

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    edit: removed drrags photo - sorry 'bout that!
    This is who set-up my rig. You could also look through the SCT Yahoo group for info too...
    http://bmwmotorcycletech.info/sidecartech.htm
    Bob may respond in detail if you send him an email, or, alternatively, if you post your question there (SCT).
    What'sa matter with yours?
    #2
  3. oppozit

    oppozit Banned

    Joined:
    Feb 27, 2008
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    341
    It's not the leading link that makes Ural steering light, as the rake and trail is identical to the earlier Ural telescopic forks. It's the 5 deg rake on the triple clamp. Have you tried reducing the trail on your LL by moving the pivot back one hole?
    #3
  4. drrags

    drrags Dorkus Malorkus

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    Neato, I will try that. What I did do was lower the top shock towers about an inch, which raised the rear half of the horizonal tubes to be more parallel with the road. This seems to have reduced the steering effort, but definitely increased the side-to-side oscillation.
    #4
  5. tony the tiger

    tony the tiger Long timer

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    I'd recommend you use the same formula I do when adjusting beer recipes... only change one element at a time!
    That way you'll know which caused what, if'n you know what I mean.
    I'll pop a pic of my LL front end for ya later tonight. (also a UNIT).
    edit: tryin' to add the pics here:
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    unladen

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    unladen
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    laden
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    laden
    All laden pictures taken with an appropriate load...
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    :wave
    TT
    #5
  6. drrags

    drrags Dorkus Malorkus

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    Ok now, that's funny! :rofl
    Thanks for the pics, Tony! :clap

    Well, I couldn't stand it anymore so I dropped the forks and looked 'em over real good. Disappointed that water poured out when I turned them upside down. :cry

    Cleaned 'em up and slid 'em back in the trees an extra 3/8" of an inch and it was a noticable improvement! I got more shake at 35mph though, but whatever.
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    #6
  7. RedMenace

    RedMenace Adventure Sidecar

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    you might contact Unit for more info. It is possible the forks on your rig weren't actually designed for it.Some people try slapping any leading link fork they can get at a garage sale or off ebay onto a bike in the mistaken belief that it it will improve handling merely because it is a leading link. If the fork was designed for a bike with a different rake at the steering head the trail will be wrong for your bike. I don't know where you could get actual numbers aside from the fork manufacturer. You could measure your trail as it sits and check it against the trail of a stock GS(if you can get that spec from BMW) and see how they compare.
    #7
  8. tony the tiger

    tony the tiger Long timer

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    Drrags - if you need contact info I'm sure I have it in da' Bums copious notes and maintenance records (archived at my haus).
    TT
    #8