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  1. 05-30-2008, 06:46 PM #1
    dirtracer4
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    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
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  2. 05-30-2008, 06:49 PM #2
    800AMSOIL4U
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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.
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  3. 05-30-2008, 06:51 PM #3
    canadaxp
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    PROX should be .005, no tighter. Do not even think of going .003

    SQUEEEAAAAKKKKKK
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  4. 05-30-2008, 08:19 PM #4
    96XPSS
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    If piping it set it up at .006" and make sure you measure from the skirts.
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  5. 05-31-2008, 10:21 AM #5
    dirtracer4
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    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.
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  6. 05-31-2008, 02:02 PM #6
    water worx
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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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