TrialsTires and How They Work

Discussion in 'Trials' started by kwisn, Sep 8, 2009.

  1. kwisn

    kwisn One Happy Dog

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    #1
  2. 10K

    10K Trail Runner

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    GooGoo GaaGaa[​IMG]
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  3. kwisn

    kwisn One Happy Dog

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    Thanks.
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  4. jjustj

    jjustj cum petris et choris

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    on my 450 exc, wish they would do the same ride and vid witha knobbie! lol:uhoh
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  5. motomotard

    motomotard Adventurer

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    very cool
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  6. kwisn

    kwisn One Happy Dog

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    "I made this video clip a couple years ago when there was a lot of mis-information about how a trials tire worked and what PSI to use. This might be useful to you at some point.

    The key point that people keep missing is that this is a RADIAL PLY tire and the real work is done by the tire body. The knobs just add some edges for a little more bite, but it’s the flex of the tire that matches the shape of the ground that does most of the work. The spaces between the knobs are calculated to give just enough room for the knobs to close as the tire conforms to objects. You can see how this works in the video. When you spin this tire, the tread can no longer match the shape of the ground, but do a quick dip in the power and the tire will “hook up” again.

    Pumping the tire up above 6 PSI stiffens the body and makes the tire more “round” with a much smaller foot print and then overworks the knobs. At 3 to 6 PSI, the knobs and tire body work together. Guys that pump this tire up to 10 PSI or more and then do burn-outs are missing the point completely.

    I have some more training videos on this site that we have been using to help new people to the sport get a good start with some of the most important fundamentals. I’m not sure if this link will show my other clips or not. If not, you can let me know and I can direct you to them if you are interested.

    Later,
    Curt Long "

    Copied from an email sent to me from the trails/recreation manager for the Entiat Ranger District out of the Okonagan and Wenatchee National Forest. Great guy, Randy. Thanks!
    #6
  7. Seth S

    Seth S Will _____ for _____

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    I run a rear trials tire now and then on my woods bike...currently a 320 lb KTM 690 and I run about 12 psi in the tire and it still works very well on the bigger bike. The only drawback is that the bike goes much faster than a trials bike and sees pavement now and then...so tread block loss becomes an issue. Still cool to see the video.
    #7
  8. prsdrat

    prsdrat Been here awhile

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    That video shows exactly what the old llantero described to me when
    I asked what tire pressure to run in Baja. As stated by him, "with
    lower pressure, the tire envelopes the rocks." Just as the picture shows.

    Great vid.
    #8
  9. Pro_Marinero

    Pro_Marinero Carbon Sasquatch

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    Curt is 2Ply on here and is a veritable Yoda of trials knowledge. I've ridden with him a few times and I always go away learning something, yet realizing how much I suck.

    The reason why the Entiat people have it is that he's worked hard to show them that a trials bike, when ridden correctly, is NOT at all like an MX bike when it comes to trail damage. I won't go into detail as to what they told him, but they came away highly impressed with how incredible these bikes are to ride on trails while not damaging them at all. If any WA guys get the chance to ride with him, do it. He's one smart cat. :thumb
    #9
  10. Seth S

    Seth S Will _____ for _____

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    Yes i agree. With the rear trials tire on an enduro bike your footprint and trail impact is minimal....its to the point that when you come to an intersection and don't wait for your buddy they have a hard time finding your tracks.
    #10