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  1. #1
    h2jim's Avatar
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    rpms up mph down

    Here's the riddle of the day. I was running 8000 rpm @ 78.8 mph. Increased rpms to 8300 and now running 76.3. Nothing has changed on the hull. Same rideplate and trim tab settings. Nothing changed. I can't figure it out.


  2. #2
    jetskibum1's Avatar
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    Your not into your limiter are you?

  3. #3
    rangermtb5's Avatar
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    How did you increase rpms??

  4. #4
    Fat Man, Little Boat Region8Ultra250X's Avatar
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    cavitation?

  5. #5
    westy's Avatar
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    Check your shoe

  6. #6

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    I know its been asked but what did you do to increase the RPMS?

  7. #7
    iron head's Avatar
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    new motor old engine had a crack in the block. RPM are down because of heat

  8. #8
    iron head's Avatar
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    Jim check the nose cone wedge

  9. #9
    h2jim's Avatar
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    My ECU is a Riva 8650 limit. Last year the ski ran 85.2 mph @ 8600 rpm. This year the best I could get was 78+ @ 8000 rpm. We discovered my block was cracked. After a new engine was installed the revs are back up. Today got to 8400 rpm but could only muster up 78.0 mph. Nothing has changed on the ski as far as rideplate and trim tab setup. It's running great and the rpms are good but the speed isn't. I'm lost as to how this is possible.

  10. #10
    h2jim's Avatar
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    It cavitates badly out of the hole sometimes and sometimes it doesn't.

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