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  1. #1

    How far off the limiter should the impeller be pitched ?

    Hi there

    Out riding yesterday and the ski (2010 FXHO) felt like it was holding back at WOT.

    It was light chop (about a foot) and thought it was coming unhocked and loosing drive but now I am wondering whether the impeller needs repitching.

    The best I can describe it was like hitting slushy snow when skiing, gliding nicely then the ski grabs/slows then off again.

    The TTO showed 7780max rpm. Its attached to cylinder 1 and wondering whether I should move it as that the first cylinder to go when the limiter kicks in.

    Any advice appreciated?


  2. #2

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    Test ski in smooth water at wide open throttle watching constant tachometer reading, the max rpm reading can some time be a spike reading and not the actual top constant rpm which is what you use to select your prop pitch/ rpm's .

    Pitch your prop to be 100-150 rpms less that what your rev limiter setting is.
    Tommy Jordan
    Last edited by K447; 02-16-2017 at 01:10 PM.

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  4. #3

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    And if your close to your target RPM in either direction you can always tune with a bigger / smaller nozzle.

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  6. #4
    lets race.... mikeFZR's Avatar
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    Quote Originally Posted by 2fast4u View Post
    Test ski in smooth water at wide open throttle watching constant tachometer reading, the max rpm reading can some time be a spike reading and not the actual top constant rpm which is what you use to select your prop pitch/ rpm's .

    Pitch your prop to be 100-150 rpms less that what your rev limiter setting is.
    Tommy Jordan
    Agreed. And while youre WOT if you see your RPMs keep dropping by 200rpms or so and then climbing back up and then falling back down, you’re on the soft limiter.

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