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  1. #1

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    GP1200R - New Build - Question

    Hello All - Just finished the break in on a new build (66V) and have a question. Here is the list of mods:

    New OEM pistons, Crankworks-TW, OSB cut stock head to 150PSI, OSB carb builds set to recipe for F/A with no chokes, free flow, Jim's cut Riva plate, Riva intake, Riva tabs, R&D nozzle, Solas 13/19

    40:1 Premix - Currently running pump gas at 91 octane - Was disappointed I couldn't get 93 - Will from this point forward.

    Now - The concern:

    All is well on the bottom and middle - pulls real nice! On the top end, the Tiny Tach maxs out at 7680. Dropped the HSAs 1/8, and the RPM max'd at 7350. So I went up 1/4(an 1/8th past the original setting), again max'd at 7680.

    I guess the rev limiter is set at 7680? Stock CDI.

    It seems like at WFO there is more left, but it isn't getting it. It almost feels like a flutter(whatever the hell that is). It does the same on the hole shot, hits 7680, levels off, but feels like there is more there.

    Where should I be looking? Protec CDI for more RPM? Re-prop ( if so what pitch)? other? Or it's just fine and I'm being too anal?

    Thanks for any insight!


  2. #2
    SMLaker's Avatar
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    What does the speedo say at 7680? curious... how about GPS speedo?

  3. #3

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    No GPS, but the stock speedo is around 63. That's partly why I think there is more there. Last year before the build, with a scored #3 cylinder, and before the compression bump, Jim's cut plate and removing the choke plates, I was hitting 68 on the stock speedo.

  4. #4
    Julian's Avatar
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    WFO would'n mind being mistaken with WOT

  5. #5
    Happily Self-Employed WFO's Avatar
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    stock rev limit is around 7450

    I dont think your tach is correct

  6. #6

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    I'd believe that. It's just a cheap little thing, but the fact that it read the same on two different HSA settings kinda leads me to think I've hit the rev limiter. Is a re-prop the right thing here? If so, what pitch should I be looking at? Thanks

  7. #7
    Happily Self-Employed WFO's Avatar
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    13/19 should work with your mods

    rev limit on that one drops the power valves, so you are going to feel it

    I'd get the tach working correctly then go from there

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