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  1. #1

    Loss of RPM and Speed

    I have a 1998 GTX Limited and the max RPM I can get out of the ski is 6200 and 52 MPH by speedo and GPS. The ski used to run at 6850 - 6900 RPM. The machine also now has a small miss in it below 4000 RPM I have tried the following with no difference.

    1. Wear ring is is fine no problems or major grooves in it. The Impeller is in good shape a few small nicks in it but nothing serious. I removed and the replaced the pump.
    2. Removed and cleaned the Raves. No change
    3. Checked the bellows in exahaust and the ring clip was off replaced it still no change.
    4. Changed the slonoid (Regulator) not sure of the name the one that the two lines of the Raves go to. No change
    5. New spark plugs no change
    6. Checked all fuses no problem

    Any suggestions of what to try next would be great.


  2. #2
    Forgot also had the carbs off and cleaned

  3. #3
    Moderator Snoman's Avatar
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    How old is your gas??? Could it be possible you got some water in your tank???

  4. #4
    Gas is new went through 3 tanks since the problem.I also ran it very low to make sure there was no water in it and cleaned the fuel filter.

  5. #5
    Moderator Snoman's Avatar
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    Did you check your cylinder compression??

  6. #6
    125-130 both cylinders

  7. #7
    speedskixp's Avatar
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    Does it have the grey tempo fuel lines? If so they need replaced. If not make sue you can blow through all of the lines. Try bypassing the fuel selector. Somethimes they get clogged. I know you said you cleaned the raves but have you tried to run it with the caps off to see iff your rpms come back? I would say to check the throttle position sensor in the throttle cable but I dont think your ski has it. Also ther should be a line going from the rave sylonoid to the rear of the ski. Make sure you can blow through it freely. It should come out in your pump tunnel via a small fitting. Also check for exhaust leaks.

  8. #8
    speedskixp

    Yes it still has the grey tempo lines on it. I have read lots about them being the cause of ski's blown up? I will check when I get home if I can blow through all with ease. You mentioned Fuel selector not sure what you are talking about. Please elaborate. Running the machine with the caps off you are refering to the red caps on the raves. Just take them all the way out and then go for a ride? There are no exhaust leaks that I can tell already checked that.

  9. #9
    speedskixp's Avatar
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    Replace the tempo lines before you do anything else. By fuel selector I meen the on/off/reserve selector. As for the rave I meen you take the caps off being careful not to lose the spring. Then with the seat off go ride it. It will be a little tuff to get going at first but if you reach down with one hand and manualy push down on one of the raves it should take off. Then release the rave. Go wide open and see if you get your rpms back. if you do then you know it is rave related.

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