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  1. #1

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    Quick dumb tuning question..

    Piston wash is not good on MAG and Center, need to richen the mixture. On my 95 sl 750, is there an air screw? I want to turn this in to richen correct?

    If I can remember correctly...
    Screw in --> More gas (richer)
    Screw out --> more air (leaner)

    am I better off just to replace the main jet...

    *sorry for the brain fart.


  2. #2
    Moderator beerdart's Avatar
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    It is not a air screw it is in parallel with the jet so out is rich in is lean.

  3. #3
    mboley's Avatar
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    Quote Originally Posted by bryan428 View Post
    Piston wash is not good on MAG and Center, need to richen the mixture. On my 95 sl 750, is there an air screw? I want to turn this in to richen correct?

    If I can remember correctly...
    Screw in --> More gas (richer)
    Screw out --> more air (leaner)

    am I better off just to replace the main jet...

    *sorry for the brain fart.
    No theires no air screw.

    NO
    Screw in less fuel.
    Screw out more fuel.

  4. #4
    Moderator beerdart's Avatar
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  5. #5

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    Should I adjust the low and high speed adjusters?!?

  6. #6
    Moderator beerdart's Avatar
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    So we have this nice tuning document from Randy and it DOES work killer.


    Tuning tips for Rookies
    *** YOU must use the tachometer to tune *** Do not trust the peak RPM reading; you must watch the tach while riding.

    Start with the screws set at 1 turn out, and tune with the tachometer for peak Rpm, then stop there and count the number of turns on the high speed screws. Write this down on a piece of paper.. Then turn the high speed screws in all the way and open them to 1/4 turn open. (Now you will be testing starts only, so no more big high rpm trips around the course). You are only turning in the high speeds to allow you to easily tune the low speeds.

    Now check the low speed screws and set them at 1 turn and do a practice start; To test the low speed setting pretend that you just jumped the start and you have to start with no holder. Hold the ski by yourself and hold as many Rpm as you can (don't blow it out first for testing) and then nail the throttle hard.... NO FARTHER THAN 50 FEET , as you are only testing the start response

    If it blubbers like a schoolgirl trying to guzzle a quart of beer, then it's too rich on the low speed screws..
    If it falls flat on the line (like someone punched you in the stomach).. It's too lean on the low speed screws.

    When you like the acceleration off the line, stop there and count the number of turns on the low speed screws. Write this down on a piece of paper.. Then re-set your high speed screw where they show the best peak Rpm earlier and try both a start and a peak Rpm run...
    It will probably "blubber" a little off the line... DO NOT turn in the low speed screws... Instead, go back out on the course and fine tune for peak Rpm again.. The blubbering off the line is caused by having too much fuel in the high speed circuit... Write down your new high speed setting on the piece of paper along with the best low speed setting that you found earlier, this will be your base-line carburetor settings.
    If the high or low speed screws are open more than 11/4 turns, then you need to swap to the next bigger jet.
    If the high or low speed screws are closed all the way, then you need to change to the next size smaller jet.


    *** If no matter what you try, it still won’t leave the line without falling on its face "lean bog"... Then try the next size lower pop-off spring in the carbs... Don't be afraid to try #95 or even #80 gram springs..

  7. #7

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    So what if you go through this, and the ski runs fine, however your piston wash sucks?

  8. #8

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    Anyone know about my last question... I'm going to take it out today to tune it.

  9. #9
    Moderator beerdart's Avatar
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    If you follow the tuning your wash should be good. If not the wash never lies.

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