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  1. #1

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    milling gp 1200 cyl. head

    friend of mine has a 1997 gp 1200 with fresh motor, hes trying to get his head milled for pump gas,is there anyone on the yamaha side that does everyone elses heads? and also looking to see what the best top end prop would be for this ski. any help would be nice. thanks in advance guys.


  2. #2
    Moderator RX951's Avatar
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    JIM PERFORMANCE
    36258 US 19 N. PALM HARBOR, FL 34684
    BUSINESS # (727)786-1177
    CELL # (727)365-5132

    and

    Lowell Horning
    http://www.2-stroke-porting.com/index.html

    and

    GroupK Performance
    http://www.groupk.com/
    Last edited by RX951; 07-08-2008 at 06:59 PM.

  3. #3
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    A good prop for a GP with pump gas compression is the Solas XO. The Solas J is the best top speed prop but the motor needs to be ported + compression to be able to pull it.

  4. #4

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    thanks guys,this is great info, im really impressed with my friends ski. its running on gps 61.9 - 62.0 with a impressive holeshot.

  5. #5
    Moderator RX951's Avatar
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    The ole skool GP's are nice !! and seems to be hard to find today. 97GPsleeper has a very very good running GP and is a very good source of information over them


  6. #6
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    Quote Originally Posted by jamiej View Post
    thanks guys,this is great info, im really impressed with my friends ski. its running on gps 61.9 - 62.0 with a impressive holeshot.

    Your friend is off to a really good start if he is running 62mph with stock compression. Awesome! Long live the GP!

  7. #7
    improvised tmg97gp's Avatar
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    Thumbs up Long live the GP

    I am his friend, I took the GP out again after some more hull & ride plate tweakin and I am now running a solid 62.8 !! several other runs with my GPS put me in the high 62's. I think that this is good for a motor that is stock except for some port work I did myself, and a J prop and Riva ride plate. What other mods. can I do?? tim g.

  8. #8
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    Get the head milled, air filters & primer kit, and fill in the ride plate, and intake grate holes (except the front two). This should get you 65.

  9. #9
    improvised tmg97gp's Avatar
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    head milling = jet changes?

    Will I have to rejet? Or can I richen it up with the high speed screws?
    Last edited by tmg97gp; 07-18-2008 at 07:46 PM.

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