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  1. #1

    785 pro motor runs fine but runs slow

    I bought a 785 pro that has aftermarket carbs, expansion chamber, race handlebars and finger controls etc. The boat starts fine and revs good in and out of the water but the top speed is (guess) 30-40 mph. It is a buyer beware EBay purchase. Do I just need to get a service manual and start checking impeller? I don't see any trash inside but have not remomed any grates or covers. Suggestions will be respected and appriciated.


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Cleveland OH
    Welcome to the Hulk walksalone.

    Is your Multi Function Display blinking a red light? and reading low fuel, low oil or overheat?

    Are your RPM stuck around 4200 RPM?

  3. #3
    I'm glad you asked that. It was my second question. The guy raced it and disconnected the display. He said that this was common in race applications, but yes it does feel like it should have a higher rpm than it does. I imagine that I just need to unbolt it and reconnect but wanting a little knowledge from people before I get too far into something I should have left alone. I have the gas mixed 32 to 1 using the highest octane and the gold label oil.

  4. #4
    Also the ski is very quick out of the water just weak mph

  5. #5

    Join Date
    Aug 2006
    Homer Glen Il.
    Post some pics of the motor also is this ski from Ohio ???

    Do a compression test and let us know the numbers

  6. #6
    Will do. The ski is from the Dallas Tx area.

  7. #7
    compression is 115 120 110
    plugs are gapped .028

    thanks for helping me with this

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  8. #8
    compression was 115 120 115

    sorry about that

  9. #9

    Join Date
    Aug 2006
    Homer Glen Il.
    can you post a pic of the rest of the hull i think i might know that boat ,does it have Lake Cities Polaris stickers on it.
    When you start it out of the water do the exhaust valves open let me know you also need to get a tach hooked up .

  10. #10
    I think has the stickers it has some from AZ when you say exhaust are you talking about the cables opposite of the carbs and if so yes they do.
    To hook up the tach will I just raise the readout and hook it up underneath? Also this ski could go cheap there is no water is West Texas

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