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Extreme bike wobble

Discussion in 'Motorcycles & Boats' started by Ershank, Aug 30, 2004.

  1. Ershank

    Ershank Formula Junior

    Aug 26, 2004
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    Jason Z
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  3. bimmer32five

    bimmer32five Formula Junior

    Nov 3, 2003
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    i think that's called a tank slapper. Ways to prevent it are getting a steering damper. Bumps in the road can cause it.
     
  4. teak360

    teak360 F1 Veteran
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    Nov 3, 2003
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    I believe that was at the Isle of Mann TT. Definitley an OH SH*# moment.
     
  5. Ershank

    Ershank Formula Junior

    Aug 26, 2004
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    I wonder how easy it is to slap a steering damper onto a ZX-10r...
     
  6. tvrfreak

    tvrfreak F1 Rookie
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    It's easy. Cheap ones are $100. Good ones $200. Fancy ones $300.
     
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  8. Ducman491

    Ducman491 Formula 3

    Apr 9, 2004
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    From what I understand there are several things that can cause it and several more to counter act it. The cause and remedy that I tend to believe in are when the front end gets light and then tries to find traction. I have read that you need to stay on the throttle and ease off of it slowly. Having never experienced a tank slapper myself I have no real frame of reference, however, I do think that once it starts to go lock to lock your best bet is a quick prayer and hope your nurse is cute.
     
  9. UroTrash

    UroTrash Three Time F1 World Champ
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    Front gets light, wheel lifts slightly, touches back down in a slight tangent to the line of travel causing a sudden jerk in the opposite direction, followed by a similar, and maybe bigger movement to the other side ended by slowly coming off throttle and allowing the clip ons some leeway, i.e. no death grip, or alternatively, you can end it as shown in the vid.

    Hard to imagine someone in the TT without a damper, likely just dialed down too far for quicker response through the tight stuff.
     
  10. Ershank

    Ershank Formula Junior

    Aug 26, 2004
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    So the point of this is.... make sure when you're accelerating hard, to bring that front end down carefully...? Would a steering damper help you in that situation?

    And the best thing to do would be to stay loose and let off the thottle?

    Thanks
     
  11. F308 MAN

    F308 MAN F1 Rookie

    Jan 19, 2004
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    The incident was most certainly at the Isle of man TT.
    The guy involved is a big mate of mine, Paul (Orrible) Orritt.... he stays with us, when visiting the island (he obviously, no longer races)
    He sufferred multiple fractures and lost a finger. He has fully recovered over the last four years, but the stomach has expanded somewhat.
    The incident in the film was only a mile from the start, and despite travelling downhill, one is still accellerating at that point... we think he hit a bump in the road which eventually caused the horrendous tank slapper. Full credit to the marshall who went immediately to pauls' assistance

    I shall let him know of his fans in the USA.
    regards, david.....isle of man
     
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  13. lamar

    lamar Formula Junior

    Feb 9, 2004
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    hello david
    i am a big fan of this race and i almost saw your friend's accident live on eurosport and always wondered how this guy was and i am really happy to learn that he is now ok
    my best wishes to him and maybe i will meet you when i go to see the races one of these days
    herve
     
  14. Ducman491

    Ducman491 Formula 3

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    Glad to hear he is okay. I try to catch the TT highlights on Speed each year. When I saw this clip a few years ago, it looked as though it could have been fatal.
     
  15. UroTrash

    UroTrash Three Time F1 World Champ
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    Damper would help if it's not let all the way out. I bet its hard to deal with a tight damper on such a varied road course as the TT so I bet they let them out. Just guessing. Anyone with personal experience on the TT?

    Off throttle VERY gently.
     
  16. ART360

    ART360 Guest

    Tank slappers are usually caused by the front end getting light, then coming back down, slightly off the direction of travel. Solution: pick the front end up off the road, i.e., get on the gas, pull on the bars, seem counter intitutive, but it works. Used to be a problem at Laguna, turn 1 is on the front straight away and is off camber, etc. Solution, wheelie until you need to brake for turn 2.

    This poor guy fell in the worst place at the TT. I was there with Ducati in 88, and sure didn't like it.

    Art
     
  17. UroTrash

    UroTrash Three Time F1 World Champ
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    I agree, see post #7. Only prob is when you get a slapper started usually you are running out of road.

    Art, how is your recovery going? ribs are hurtin' things!!
     
  18. ART360

    ART360 Guest

    I'm going to practice on the cart tomorrow, that'll tell me how well they've healed.

    Art
     
  19. F308 MAN

    F308 MAN F1 Rookie

    Jan 19, 2004
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    Thanks guys for the comments re paul.....i shall print the thread and send it off to him.
    Dampers are a necessity here.....the top boys have an adjustable unit, controlled from the bar grips.....the poor boys have to set for an 'average' throughout the course, similar to suspension settings.
    Anybody ever visiting the TT ???, then you must give us a shout for at least a beer.
    cheers for now, david
     
  20. ART360

    ART360 Guest

    Dave:

    Will be there in 07. I'll drop you a line then. Bringing the plane over, so we won't have to ride the packet.

    Art
     
  21. SteveNSX

    SteveNSX Rookie

    Jun 18, 2004
    40
    Steering dampner will slow but will not prevent a tank slapper.
    You don't panic and put forward pressure on the bars. I have
    had such violent slappers on the track in which the force caused
    the brakes calipers to be compressed to the point I did not have
    brakes until I gave them a quick pump. Lightweight, high hp short
    wheelbase bikes are most prone. The late 90's GSXR 600's were
    notorious!!
     
  22. F308 MAN

    F308 MAN F1 Rookie

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    ....as wre the suzuki TL 1000's ....d
     

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