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  1. #1

    Factory carb setting for high/low speed adjustment.

    Does anyone know where I should set my carbs? All the way in and how many turns out for each adjustment?

  2. #2
    I wanna go FAAAAASTer!! CDW78's Avatar
    Join Date
    Mar 2010
    Might be helpful to know on what kind of ski, first?

  3. #3
    Wow. I guess that would help.

    It is a 1998 GP800 with the 44mm I Series Mikuni's. I just ordered rebuild kits including a new needle and seat. The machine is a little hard starting when cold so I hope this rebuild and a few adjustments will help. I just dissembled the power valves and cleaned them up and rplace the o-rings etc. I am going to replace the fuel/oil lines this weekend. I greased the PTO and pulled the cone off the jet and re-greased it. I will change the plugs and fuel filter. What else do you guys recommend?

    I guess I also need the proper/factory carb adjustments? I will will mark down where they are currently at and go from there. From full seat I need to know how many turns out. Are both cylinders adjusted the same? From my understanding the main jets vary a bit from one another (155 and 157).


    It is my first time rebuilding carbs so hope all goes well. I did print the service manual from Mikuni for reference. Any tips one might have on the removal/disassembly and reassembly would help.

  4. #4
    I wanna go FAAAAASTer!! CDW78's Avatar
    Join Date
    Mar 2010
    Id check the oil lines if not already premix. replace if needed or dbl clamp.
    Rebuilding the carbs arent really that big of a deal, take your time and make sure you pay attention to what you take out and put back in!!
    Do 1 @ a time too

    Sure some one else will chime in with more info...

    I got this from the the thread below - hope it helps.

    800 - Low Speed – 2-1/4 +/- ¼ (M),1-7/8 +/- ¼ (P)
    High Speed – 1/2 +/- ¼

    1.2 Needle/seat
    157.5 Mag main jet
    155 PTO Main jet
    85 Mag Pilot jet
    90 PTO Pilot jet

    Of course it doesnt tell you what pop off should be.

    That is your stock 800 settings...seems a little steep on the low side,but thats what the manual says,thats what it says for the jets and N/S also.

  5. #5
    Thanks for taking the time to reply. I am going to do the oil and fuel line this weekeng. Does the oil pump require bleeding after replacing the lines or just hold the pump wide open upon start up. I will mix the first tank to be safe and to make sure oil is being used.

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