What's happening in this video?

Discussion in 'The Perfect Line and Other Riding Myths' started by indr, Jul 6, 2013.

  1. indr

    indr .

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    #1
  2. omeoxlv

    omeoxlv Been here awhile

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    Havent slow moed it or anything but would guess not going that quick in first place and (most important) stood up!
    He caused it by giving full throttle and then backed right off.
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  3. DSM8

    DSM8 Where fun goes to die....

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    Perfect example of a highside but was going slow enough he did not get tossed off bike. Good save on his part.
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  4. markie*mark0

    markie*mark0 Adventurer

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    poor control in the first place, if you watch carefully you can see the on/off of the throttle, combine that with the weight transfer of the bike and the rear looses traction.

    highsides tend to kick you out of the seat, the good thing with that is all of your body weight is instantly transferred to your pegs, this means the centre of gravity is put as low as possible to make the bike more stable.

    combine the lucky kick out of the seat with an instinctive "turn into the skid" and he saves it.

    Work on positive throttle control for next time and this wont happen
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  5. DAKEZ

    DAKEZ Long timer

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    He cut the throttle and used the clutch to help the rear wheel regain traction... And let the bike have the freedom to right ITSELF.
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  6. DAKEZ

    DAKEZ Long timer

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    :fpalm weighting the pegs does NOT lower the center of gravity.


    :rofl
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  7. superhobie

    superhobie Soil Sampler

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    Never touched clutch :huh
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  8. rocker59

    rocker59 diplomatico di moto

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    To answer the OP's question, when the rear end kicks out, do not chop the throttle. Slowly roll off the throttle as the rear end comes back in line.

    If you leave too much throttle, the rear will wash out and you'll low side. Chop the throttle too quickly and it will snap back in line and high side you.

    Practice sliding a dirtbike and you'll see what I mean... Though, it's not really something you can practice for on the street.
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  9. JimVonBaden

    JimVonBaden "Cool" Aid!

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    It started by braking and unweighting the rear tire. Watch closely and you will see the front squat.

    As for the save, back on the gas lightly by reflex, and standing up to weight the rear again. It is a common theme on Mulholland Drive!

    Jim :brow
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  10. lnewqban

    lnewqban Ninjetter

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    He didn't.
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  11. rocker59

    rocker59 diplomatico di moto

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    I just re-watched the vid and didn't see his fingers on the brake (or the clutch).

    The slide was throttle induced. There are hundreds of vids on the web of bikes doing the same thing at the same spot on that road.

    He rolled on too much throttle on the exit and lost rear traction, putting him into a power slide. He then chopped the throttle a little too quickly and almost high sided when the rear end came back in line.
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  12. rocker59

    rocker59 diplomatico di moto

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    Well, at least he held on tight during the rodeo.
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  13. JimVonBaden

    JimVonBaden "Cool" Aid!

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    You are right, same effect though. I could see his wrist as he let up on the throttle.

    Jim :brow
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  14. lnewqban

    lnewqban Ninjetter

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    Yes, more or less, ......................and he was lucky that the surface upon which the recovery happened was still slippery, allowing the rear re-gain traction gradually.

    This guy was not as lucky:

    http://www.triumph675.net/forum/showthread.php?t=40391
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  15. Navy Chief

    Navy Chief Long timer

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    Great photo sequence of exactly what happens during a highside... Glad the rider was okay.
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  16. lnewqban

    lnewqban Ninjetter

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    [​IMG]

    This is what the rider stated after the fall:

    "Interesting. I see where folks note I chopped the throttle. Yet the slide sideways continues for some distance and time beyond that point. Thoughts? Did the rear end get light with the momentary chop, which in turn caused the rear wheel to spin faster and more sideways instead of immediately hooking up? If I had not chopped, would it had hooked up sooner possibly saving the highside? Funny thing is I didn't think I had chopped the throttle really, in my mind when it was happening. But from the photos, apparently, I did. I know I was (in my mind) not panicking, but instead I was looking at my next apex point (the 9/10 complex at Chuckwalla is an "S" bend curve that leads from a left turn to a right turn, which is why my eyes are then looking to the right) for that split second trying to will myself to get straight and get there, but to no avail.

    As a side note: The throttle chop was only one of several mistakes in that corner for me it seems. First was poor line selection that put me in an area of the track that full of fine dust. In the first few photos, you can see the trail of dust as my knee puck slides. Reason: I was experimenting with going deep into the corner for a different line through the 9/10 complex. Obviously not a good move. At least I can now attest to that. Second problem seems to me was that I didn't have my body mass far enough off the side of the bike, which increased lean angle of the bike itself in an already off-camber corner. If I had the bike just a little more upright at the same speed, maybe I could have had more contact patch on the track and avoided the slide to being with.

    Oh well, at least I have some cool pics to teach my kid what "not" to do at Chuckwalla."

    http://forums.superbikeschool.com/index.php?showtopic=2165

    The problem is not that the rear tire skids sideways (while the rear of the bike gets lower), the bike can continue rolling on the front tire in a controlled manner (flat track racing, motorcycle dragging).
    The problem appears when that rear tire suddenly regains grip and stops slipping (rolling or locked) to start rolling without slipping.

    If that contact patch of the rear tire is significantly out of alignment with the contact patch of the front tire at the moment it regains grip, a violent re-alignment of those and kick-up of the seat happens.

    Racers are trained to stand up from the saddle, so that violent snap up doesn't kick them on the butt and catapult them to a high side.

    Note that for that for that sudden regain of grip or snap happens, 1) the contact patch of the rear tire needs to be unloaded (from torque or brake) and 2) it needs to be skidding over a surface that can provide good grip.
    In the case of the OP, the first thing happened (rider rolled-off throttle reducing torque to the tire), but not the second (surface was still slippery).

    MSF courses teach to keep the initial load on the tire constant during a rear skid as long as the rear tire is way out of alignment.
    That initial load can be excessive rear brake (keep it locked-up) or excessive torque (keep or slowly reduce throttle).
    If you let go either one while both tires are aligned, no highside fall will follow.
    If you, like the rider in the OP's video did,
    let go either one while both tires are way out of alignment but on a slippery surface or dirt, no highside fall will follow either.
    :muutt
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  17. JDK111

    JDK111 Been here awhile

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    He eased off the throttle just enough to stop the low side from continuing (he didn't touch the clutch) and steered in the direction of the slide just enough to stop the high side from happening when the rear wheel gained enough traction for the bike to RIGHT ITSELF.
    Dude knew what he was doing.
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  18. sphyrnidus

    sphyrnidus born to ride

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    If he knew what he was doing, he wouldn't have put himself in that situation :jerko
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  19. JDK111

    JDK111 Been here awhile

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    Funny ... I must have missed the part of the vid where he crashed :lol3
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  20. markie*mark0

    markie*mark0 Adventurer

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    ok douch bag, maybe a bad explanation, but getting out of the seat and onto the pegs helps the bike work less and become more stable.
    #20