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  1. #1
    Hydrotherapy's Avatar
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    quick power valve question..gp1200r 2000

    back on deans POS tonight...

    what rpm do the power valves open...??

    other than manualy operatin by the wheel under rubber boot, can they be cycled with engine off to check they work, i.e feeding them 12v and watching..

    when they cycle do they open close or visa versa,

    thanks guys...paul..


  2. #2
    XLTNoob
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    From what I understand, basic operation is this..

    When idling, the powervalves are closed.
    Once the revs reach a certain RPM (mabye progressivly as the rpm's increase?) then the powervalves open.

    Bigger hole for gasses getting out of the cylinder means more fuel can get in the cylinder, which in turn makes more power.

    as for cycling while the engine's off, I've got no clue..*checks his manual*
    *EDIT* Check page 392 and 394 in the service manual.. can't printscreen pages up at work.
    Last edited by Jolly Roger; 07-26-2007 at 04:24 PM.

  3. #3
    Hydrotherapy's Avatar
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    testing results please help

    can any one tell me when the power valves should start to open in rough rpm numbers....
    deans power valves are not opening fully on the water and when they do open the small ammount they do, they only start to try to open at aprox 5800 rpm and never obtain fully open like i have marked after setting cable pully to correct spec from manual..
    and his ski it only reaching 6250 rpm

  4. #4
    All hail the Chief! fullboogie's Avatar
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    Pull the PV motor, open the case, and look for the corrosion on the circuit board right where the 12V wire attaches. It happened to 3 of mine, which is what made me go gas valves. If this is your problem, get a good used motor and seal the two halves of the case with silicone before reinstalling.

  5. #5
    Hydrotherapy's Avatar
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    thanks dave will do,

    the motor cycles for cleaning and i marked fully open and fully closed positions on the motor wheel,on trailer it will open fully with a hard blip of gas, but with the seat off in the water and looking at marked wheel it wont open nearly enough at wot i think holding the ski back to the 6000 rpm mark..
    did yours do the same ???

    thanks for reply

  6. #6
    WE DONT DIAL 911 RDH's Avatar
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    yes they should cycle, open then close, as soon as engine is shut off...

    try unplugging the servo,opening them all the way and going for a ride, see what rpms you get...

  7. #7
    Moderator RX951's Avatar
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    Quote Originally Posted by saltygpr13 View Post
    back on deans POS tonight...

    what rpm do the power valves open...??

    other than manualy operatin by the wheel under rubber boot, can they be cycled with engine off to check they work, i.e feeding them 12v and watching..

    when they cycle do they open close or visa versa,

    thanks guys...paul..
    they open roughly around 4950 rpm

    they cycle [open close] after the ski is shutoff. you can start the ski briefly and watch the servo motor cycle.

    Here is a test to make sure the PV motor works


  8. #8
    Moderator RX951's Avatar
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    Here is a video I took with my phone to show how the cables cycle after it is breifly run then shut off


  9. #9
    Hydrotherapy's Avatar
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    thanks billy your a star

    his does cycle/clean after switch off like yours...

    talked to yam mechanic today and he said the cables can be seen to start moving at 3000 rpm and are fully open postion at aprox 5900 rpm,
    can anyone confirm or deny the above to clarify my findings..
    his pv only moves at 6000rpm on trailer and opens in one go not gradual..just 6000 dam fully open

    with the seat off,on the water,watching pv marked wheel,no movement till 6000rpm and when it does move its only opened half as much as on trailer..
    Last edited by Hydrotherapy; 07-27-2007 at 12:06 PM.

  10. #10
    Duke's Avatar
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    My observation was around 5000 to 5500. It was hard to hold constant rpm when I looked at it. Wasn't very gradual though.

    Have you manually opened them and disconnected the plug to see if it revs out more?
    Last edited by Duke; 07-27-2007 at 12:13 PM.

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