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Thread: Above 8500 rpms

  1. #1
    ercBOOSTED's Avatar
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    Above 8500 rpms

    If I plan on going above 8500 rpms, do I just need to do the valve train upgrade or should I be doing other internal upgrades?


  2. #2
    philip_gpr's Avatar
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    how much above 8500?

    wth the reflash, R&D set the rev limit at 8750 so they obviously feel we can safely run at least to 8750 without any valvetrain work

  3. #3
    RUSH.'s Avatar
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    I am running stock valve train over 8500 but I wouldnt recommend it.

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    MPower's Avatar
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    Quote Originally Posted by philip_gpr View Post
    how much above 8500?

    wth the reflash, R&D set the rev limit at 8750 so they obviously feel we can safely run at least to 8750 without any valvetrain work
    Why would that mean R&D thinks its okay to not have valvetrain work? I wouldn't assume that at all.

  5. #5
    speedskixp's Avatar
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    I'd be looking at going with forged internals if planning to run over 8500. Keep in mind that 8500 in the water can meen over 9000 when coming unhooked.

  6. #6
    zx11rider's Avatar
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    wish Yamaha would built them with forged internals, Yamaha produce other motors which redline at 13000 Plus that stay together.....

  7. #7
    SHOBiz's Avatar
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    Quote Originally Posted by speedskixp View Post
    I'd be looking at going with forged internals if planning to run over 8500. Keep in mind that 8500 in the water can meen over 9000 when coming unhooked.

    Damn straight and that could pop that engine real quick

  8. #8
    JD 1's Avatar
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    deff dont need forged internals. Forging the motor is a easy $10K job remember.

    depends where your rev limiter is set?

    If you want to set the limiter up at 8700 and run around at 8550to8650 you will be fine as is.

    We have a FZS with stock motor that we plan on running all year with a 17lb charger at 8700. It will be a test dummy to see how far we can take a stock block. Ive yet to see a sho motor seize/blow up due to "to much boost" or over reving.

    The Riva valve train is a great kit but needs a Professional install to successfully accomplish, keep that in mind.

  9. #9
    KamikazeGPR's Avatar
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    Question. What would motivate R&D to change the original rev limits on the R2 reflash from 8400 to 8750. Knowing it's pushing the limits on the cast internals for long term use?

    8500rpm seems to be the consensus as to what is acceptable for a rec rider long term. To the people that have already gotten the R2 reflash. What are your rpm's with the 155mm skat 13/25 and the skat 160mm 13/23 or less.

    With the stock ecu. We know the rev limit is 7750. so we use props to keep us at 7700 or less. What can be done when your rev limit is set at 8750 to possibly get the rpm's down to the 8500 range?

    The reflash and inter cooler are my next mods. But, I'm not about to pull the pin on a grenade in my ski. I still owe $10 grand on it.

  10. #10
    SHOBiz's Avatar
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    Quote Originally Posted by JD 1 View Post
    deff dont need forged internals. Forging the motor is a easy $10K job remember.

    depends where your rev limiter is set?

    If you want to set the limiter up at 8700 and run around at 8550to8650 you will be fine as is.

    We have a FZS with stock motor that we plan on running all year with a 17lb charger at 8700. It will be a test dummy to see how far we can take a stock block. Ive yet to see a sho motor seize/blow up due to "to much boost" or over reving.

    The Riva valve train is a great kit but needs a Professional install to successfully accomplish, keep that in mind.

    Despite me having a valve drop even I don't think that is true. We don't all need to run off to a shop to have the valve train upgraded.

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