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  1. #1
    Adam's Avatar
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    Gp1200R porting pics

    I have recently ported my GP1200R cylinders , they now are very close to this exhaust port pic from Judge porting. 72% of bore diameter exhaust port width . Having read Gordon Jennings 2 stroke book I was inspired to port the cylinders.
    These are the plug colours and one of my cylinders.
    It pulls extremely hard with 150 mains and 110 lows
    I am running an Advent 1290 CDI on curve 84 .
    I will be doing some smooth water speed runs this week , itís feeling good so far .
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  2. #2
    Hey Adam... cool post man... do you have any detailed pointers on this subject of port timing on these engines?

    I have the PV 1300R engine but I have only managed to lightly remove some casting imperfections, did you get into exhaust port timing or just light massaging and polishing of the cylinders transition areas?

    You can PM me if anything I know some people can be very picky about sharing their results. Regardless looks good and aggressive man. Aggressive shaping of it might need to up the fuel pressure and premix huh? lol

    It's good to see people still messing around with these still, even though they are a pain 2 stroke is like a love hate relationship.

  3. #3
    Adam's Avatar
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    Pm sent

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  5. #4
    Adam's Avatar
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    Just saw this highly modified GP1200R cylinder porting , I believe its close to 99% of bore size . I would love to know what sort of numbers these produced .
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