Japanese National Series: more Yamahas

Discussion in 'Trials' started by heffergm, Mar 11, 2018.

  1. VxZeroKnots

    VxZeroKnots Long timer

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    Most racing is like that, it also looks like they either don't have a cross-your-line rule or it isn't strictly enforced.
    #21
  2. heffergm

    heffergm Long timer

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    They do have the cross your line rule. As with most high level national series, it really only applies if both wheels are on the ground. Meaning, if you're near your line and you throw a big rear hop to cross it, it isn't considered crossing your line. It seems to be a bit of a loophole ;)
    #22
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  3. motobene

    motobene Motoing for 46 years

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    Bingo. That's a work around regarding the formatting issue.

    It isn't easy to shrink heads and do so reliably. HRC and Beta have done it well. What helps is trials motors do not have to be as robust as motors needing to make maximum power, which the inclined Yammer motor is targeted toward.

    I wonder how Yamaha dealt with typical low total inertia of the braap! motor? The center cases on these can be designed for smaller cranks.

    I don't know the WRX motor intimately, however.
    #23
  4. heffergm

    heffergm Long timer

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    If I had to guess I'd say they didn't bother. It's the fastest revving (up and down) thing I've ever heard (on a trials bike).
    #24
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  5. Norman Foley

    Norman Foley Devotee of the Husqvarna

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    I just looked back at Trials Magazine UK's issue on '17 Japan Trial GP. There is a short piece on the Yamaha TYS250F. The editor John Hulme is an old friend of Mr Kimura, the Yamaha Trials project leader. They go back to the Majesty and TY Mono days. Kimura said the engine is a YZ, not a WR and that the long head pipe is to tame the power. He won't reveal the actual capacity of the engine or the weight of the bike. The '17 bike had a Scorpa 2T rear section, including the silencer. You can see in the '18 vids and pics, that the silencer is now a more 4T enduro type.
    Pretty hard to shrink the head on a twin cam, compared to Honda and Beta single cam designs.
    #25
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  6. motomofo

    motomofo Been here awhile

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    From what I’ve seen from following Sherco07 on Instagram (if you don’t follow this, you should), one of the guys is riding with the old school, five valve head... with the intake and exhaust in the “proper” position. Basically an updated, old Scorpa I suppose.
    #26
  7. heffergm

    heffergm Long timer

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    Yeah, that's last year's bike that Nozaki and a guy I don't recognize are on this year. It's a standard layout but it's still a WR based engine.
    #27
  8. motomofo

    motomofo Been here awhile

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    Didn’t Kuroyama ride the reverse head bike last year? That would make the standard bike from two years ago, at best.

    The thing that’s crazy to me is the way the engine cases hang down really low, with that curved skid plate.
    #28
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  9. heffergm

    heffergm Long timer

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    I don't think he did, but I'll go look...
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  10. heffergm

    heffergm Long timer

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    Yup, you're right . It was the reversed head in 17 for Kenny. The old frame fooled me.
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  11. heffergm

    heffergm Long timer

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    This is great, from a few years ago. No one makes it through in the event, do they all come back after to try it some more:
    #31
  12. Norman Foley

    Norman Foley Devotee of the Husqvarna

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    '17 bike with older silver frame and Scorpa 2T silencer.

    '
    [​IMG]
    '18 bike with new black frame and WR Enduro type silencer.
    [​IMG]
    #32
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  13. Norman Foley

    Norman Foley Devotee of the Husqvarna

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    '18 bike left side...
    [​IMG]

    Left side of '18 bike, which shows top engine mount in natural aluminum....
    [​IMG]
    #33
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  14. lineaway

    lineaway Long timer

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    Everything about that engine is just so wrong for trials.
    #34
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  15. Ymirtrials

    Ymirtrials Been here awhile

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    So wrong but they seem to make it work just fine....
    #35
  16. KevinBB

    KevinBB Trials Addict (I drank the kool-aid)

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    Yes, I follow him on IG - On IG he goes by Shiverkye - really good guy!!
    #36
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  17. VxZeroKnots

    VxZeroKnots Long timer

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    Do any of the trialGP big names ever come to these events? Seems like a way better use of time than xtrial. Do these guys ever compete in FIM events?
    #37
  18. Norman Foley

    Norman Foley Devotee of the Husqvarna

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    Japan round of Trial GP has a ton of local wildcards, compared to other rounds. At least the top 5 Pros ride the Trials GP Class and others ride Trials 2 and Trials 125.
    #38
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  19. lineaway

    lineaway Long timer

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    The Japanese terrain is terrible, That is why you hardly see any riding besides Motega Raceway. The Jap riders are pretty crazy. And most GP riders like to stay in Europe.
    #39
  20. VxZeroKnots

    VxZeroKnots Long timer

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    Always a ray of sunshine :lol3
    #40