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  1. #1

    What is the piston clearance on a 785?

    Anyone have a manual handy? Need to know what the stock specs are on piston clearances for the 785. Installing ProX's


  2. #2
    800AMSOIL4U's Avatar
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    std: .003-.005" 0.075-0.13mm
    limit is .008" .20mm
    This is what I have listed in my 97 785 book
    Last edited by 800AMSOIL4U; 05-30-2008 at 06:52 PM.

  3. #3
    canadaxp's Avatar
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    PROX should be .005, no tighter. Do not even think of going .003

    SQUEEEAAAAKKKKKK

  4. #4
    96XPSS's Avatar
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    If piping it set it up at .006" and make sure you measure from the skirts.

  5. #5
    From my measurements, the piston has about .00475 clearance built in. I didn't have a manual and wasn't going to assume that was it. Thanks for the info guys.

  6. #6
    Tool Bag water worx's Avatar
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    There is no "built in" clearance.

    You take the size of the piston & make the bore .0055 bigger than the size of the piston.

    I set my ProX up at .0055.

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