Leading Links

Discussion in 'Hacks' started by Strong Bad, Dec 17, 2014.

  1. Dan Alexander

    Dan Alexander still alive and well

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    Yes, that was where I was going with the thought of using conventional triple clamps. Is the GS headstock to weak to support the weight so more bracing is needed?


    I was worried I was sounding like a babbling idiot ..... oh wait I usually am
    #41
  2. davebig

    davebig Another Angry Hun !

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    http://motocrossactionmag.com/home-page/the-fork-design-that-almost-mad-eit-big

    Mobec Germans always have an idea
    http://mobec-international.com/technical/steeringsystems/03351a9ff30d34e16.html
    Mobec on a R12gs they've spaced the tele way up
    [​IMG]
    Looks like disk and calipers float.
    At this point I'd like to point out we're in an international economy and the Euro and dollar are not very far apart and the Germanic horde speaks english usually with a British lilt.
    Then there's the EML Extensodive front from this thread http://www.advrider.com/forums/showthread.php?t=779654
    [​IMG]
    #42
  3. Strong Bad

    Strong Bad Former World's Foremost Authority Supporter

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    Do you have a link to Pez's thread, please?
    #43
  4. davebig

    davebig Another Angry Hun !

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    #44
  5. bk brkr baker

    bk brkr baker Long timer

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    Dan, can you spot a headstock in this image of a telelever chassis ?


    [​IMG]

    The headstock in this system is replaced by the upper yoke mount and the A-arm. The steering pivots on the ball joint on the end of the suspensions "A" arm and at the upper yoke.
    Quite unconventional and therefore nowhere to mount a conventional set of triple trees.
    I'm sure someone will be able to explain it all better ,as I am not a BMW owner and not a native Canadaian speaker.:D
    #45
  6. Dan Alexander

    Dan Alexander still alive and well

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    :baldy

    What the hell am I thinking?

    Suffering a Man Cold (possibly a strain of Ebola I tell my GF) and I'm spaced out. I've been riding telelevers since I got my new 99 R11S with only 2 years off to ride my Super Enduro, I should know what's under the tank

    Thanks for being gentle with me
    #46
  7. DRONE

    DRONE Dog Chauffeur

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    Kuhunge broke his telelever right at the ball joint. Note that on his rig, the A-arm upper strut (the rigid piece that replaces the front shock) is very short which places the lower fork bridge way up high on the leading link forks. I'm wondering if there is an ideal length for that strut. By having the lower fork bridge so high up, doesn't this put more twisting force onto the telelever than if you used a longer strut that put the telelever in more of a "neutral" position?
    #47
  8. DRONE

    DRONE Dog Chauffeur

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    Here's a picture of Kuhjunge's rig--you can see where the telelever sits way up high--

    [​IMG]

    And FWIW floating caliper and the axle's higher than the pivot, apropos of nothing.
    #48
  9. Bobmws

    Bobmws Curmudgeon At Large

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    And wouldn't a longer strut relieve the more severe angle at the top where the flexible connectors are?
    You would just need a more severe bend on the legs them selves, or a shorter swingarm to get the trail reduction.
    #49
  10. davebig

    davebig Another Angry Hun !

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    Well what can we surmise without an engineer, Strong or FR700's opinions. That would be a slow failure and you should get some warning and a easy fix. I know of a GS that may receive a preemptive strike ! The questions of course how hard has he been bottoming the front end ? Is he still trying to use the rubber bushings at the top ? Onward
    #50
  11. M37cdn

    M37cdn Adventurer

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    That failure looks like it was cracked on one side first then tore away the other side at the point of failure,
    time to add some metal around that area, or build a new telelever out of thicker steel
    #51
  12. DRONE

    DRONE Dog Chauffeur

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    The telelever is all aluminum, isn't it Dave? Either way, yes, it would seem a preemptive reinforcement of the A-arm would be in order.
    #52
  13. cleatusj

    cleatusj Dirt floor engineer

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    From the mind of a hillbilly raised in Texas.

    Is there any reason one could not just use bent legs to move the axle fowrard and just leave the telelever as designed? Might need a stiffer spring.
    #53
  14. M37cdn

    M37cdn Adventurer

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    I was judging that it was steel by the color of the metal and the HAZ ( heat affected zone) of the welds
    #54
  15. davebig

    davebig Another Angry Hun !

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    On the 1100/50 gs and rt they are two pieces of stamped steel with a bushing inside where the ball joint bolts thru. The change steering geometry with different ball joint mount( lower triple clamp)
    The R1200's are cast aluminum and BMW used more meaty casting at the ball joint area between the GS and RT anyway, it appears they use the same casting but place the ball joint differently between the rt and gs, for different steering geometry.DB

    Repair $55 on fleabay http://www.ebay.com/itm/261210631341?_trksid=p2060778.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT
    Add metal and powder coat as needed !
    #55
  16. davebig

    davebig Another Angry Hun !

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    Oh oh this ain't your first rodeo ! I think what your seeing as HAZ is the bushing that the ball joint bolts thru. The telele A-frame is 2 pieces of stamped steel probably contact welded together over a bushing and then bearing mounts added to the other end.
    More Telele info here:http://advrider.com/forums/showthread.php?t=786238&highlight=dedome mine has 40 k miles and one 8 point buck and no issues.
    #56
  17. davebig

    davebig Another Angry Hun !

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    That ain't the craziest thing anyones ever said,I wonder why no one with a big Tig welder hasn't used the parts from several sliders (there's nothing inside them except some bushings to move the axle ahead the way DMC does with the V-Strom links, but with that much welded aluminum it might be courting disaster. Easiest best idea :http://advrider.com/forums/showthread.php?t=786238&highlight=dedome Plagiarized from a French sidecar builder :D

    But this is a leading link thread !!!!!!!!!!!!!!
    #57
  18. DRONE

    DRONE Dog Chauffeur

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    Well, yes, but I brought this up because Strong Bad is trying to figger out LL's for his 1200GS and, after Kuhjunge's failure, it seems like Strong would want to know how to strengthen the a-arm or how to design the LL's to reduce stress on the ball joint. So we are ON-TOPIC!!
    #58
  19. davebig

    davebig Another Angry Hun !

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    That was for me as I was wandering off with Cleatus :D
    #59
  20. FR700

    FR700 Heckler ™©®℗

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    Leverage ratio didn't do it any favours.



    .
    #60