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  1. #1

    It takes a village

    Ok 94 SL 750
    New SBT with 2 ½ tanks through it
    Fresh genuine rebuild kits with new needle and seats
    Triple pump, new line
    18psi pop off, stock air box with the black rubber thing
    Stock everything except Vforce reeds
    There’s my plug after one tank.
    Speedo says 49mph and 5500rpms is all she will do, this pisses me off because my other ski, a $400 junk ski from behind a warehouse with 150 hours will do 6000rpms and jumps out of the water no problem. Mine on the other had can’t be nailed from a dead stop, and just doesn’t seem to have to power that the other one has. To me it seems like the new motor should be running away and leaving him.
    Anyway that plug was ran with the carbs at stock setting plus about a ¼ turn out on the highs just to be on the safe side, and it still looks very lean to me.
    I just went out and played around with the lows and I cant get it right, ½ out on the lows it falls on its face any more out and it bogs.
    Help me please!
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  2. #2

  3. #3
    Saving the Manuals every day.. TheBlueMartin's Avatar
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    Isn't 18psi to low for a stock air box? I'd think your high speeds are coming on early

  4. #4
    casey67's Avatar
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    Black plug=rich
    White plug=lean

    Low speed mixture adjusting screw= low rpm adjustments (take off)
    High speed mixture adjusting screw= high rpm adjustment (3500-4000rpm + )

    engine run at low speed=plugs show low adjustment
    engine shut off at high rpm=plugs show high adjustment

  5. #5
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Are the carb adjustment needles damaged?

  6. #6
    johnsonmtz's Avatar
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    When you say you can't punch the throttle.....what happens?

    Does the ski just nearly (or actually does) die?
    - If it just falls flat with an UUUGGHHHH sound that means it's lean on the low end.

    Does the engine blurble and have a boggy sound?
    - If it sounds like blurble, blurble, blurble and then finally comes out of it and goes that means it's rich on the low end.

    Do you have the carbs adjust properly for low and high speed screws? If you're running too rich on the top end that will kill your WOT RPM.

    You should be seeing somewhere around 6200 RPM on an SL750.

    KJ

  7. #7
    Needles are not damaged checked that, its deff lean on the low end no doubt but richening up the needles does nothing and according to mukuni tuning guide your low speed needles should really only adjust your idle mixture and your pop off pressure has more to do with your take off. The plugs really worry me, I put new ones in it after this pic and the still come out with that bright ass shiny base ring, and no one can seem to tell me what that means. I sure as hell have never pulled a plug and found no color or build up on the base ring. And it’s not running "bad" I can go out and run all day, have fun do spins and stuff I just don’t want to burn this thing up.

  8. #8
    Saving the Manuals every day.. TheBlueMartin's Avatar
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    If your plug is clean as new after running it, its being washed off by excess fuel. You need to lean it down until it gets dark in color.

  9. #9
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    Take a look at the piston wash thru the spark plug hole,that will give you the best indicator what is happening. Also some oils leave very little residue on plugs. The flat off the threads tell you nothing on rich or lean.

  10. #10
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    I know what the manual says, but the low speed screws DO have a hand in your take off.

    What size needles and seats do you have in there now?

    Are they new?

    What is your pop off pressure?

    What's your fuel pressure at idle and WOT?

    Are your carbs in sync?

    Does applying the choke help or hurt?

    Are your reeds good?

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