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  1. #1
    ecpChris's Avatar
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    What could be causing slow speed?

    I went riding today for the first time since sept.
    07 gpr milled head by jim, 1200 grate, ppk, 14/20, box stock R&D plate, airbox mods, d-plate, blue ff, jetworks, efi set 4417. air temp 46 water temp 40.
    Top speed 66.2?? wtf
    one thing that i did notice although i dont think i can attribute to slow speed was the tube for cooling passage #3 on the head popped off. when i pulled the seat the hull was full of water and there was exhaust smoke.
    would that alone cause such a slow speed? anything else i could be missing?
    also on takeoff ski cavitated a little. thanks


  2. #2
    ecpChris's Avatar
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    oh yeah and i weigh 196 and rpms were 7150 (commercial tiny tach)
    i think when the hose popped off the rpms were shooting up to 10000 on the tach and the ski was sputtering up top.

  3. #3
    PuprleNuprleGPR's Avatar
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    Has your tunnel been reinforced? A cracked/leaking tunned will cost you about 5mph

    Edit - Just checked that your only top speed mods are the prop and rideplate. The FF, D-plate, and 1200 could probably negate any top speed gains...

  4. #4
    ecpChris's Avatar
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    i have milled head and efi as well as f/a

  5. #5
    Moderator beerdart's Avatar
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    You have #3 dumping into you hull and you are loosing speed?

  6. #6
    WATER WOODY's Avatar
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    How much water in the hull? Did you fix the leak and go run the ski hard? Water ingestion is no good.What speed/rpm did it normaly run? PV's opening?
    Last edited by WATER WOODY; 03-23-2008 at 07:28 PM.

  7. #7
    Duke's Avatar
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    If there was exhaust smoke inside the hull you lost your FF or something. Just the smoke alone will kill your speed. Need to tear everything apart and inspect.

  8. #8
    ecpChris's Avatar
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    by the time i realized there was water/smoke/#3 hose off i was idling back to the trailor. Im going to tear it apart and try again next week

  9. #9
    ecpChris's Avatar
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    and in addition I have no baseline. Last year my ski was completely stock except for dplate and grate. This was my first time out after all the mods

  10. #10
    www.eastcoastpwc.net Scott's Avatar
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