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  1. #1
    Rhoup's Avatar
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    Hot Rodding A 787

    Is there any way to hot rod the 2 stroke rotax 787 to run with the supercharged 4 strokes?

  2. #2
    Team Bilford's Avatar
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    No.
    I had a Group K Sleeper Kit 787 XPL that would run 60. Anything more than that and you give up a tremendous amount of reliability.

  3. #3
    Rhoup's Avatar
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    How do I get it to run at least 60?

  4. #4

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    What ski is the motor in? If a GTX, it will be hard to get anything over 60 mph without bigbore and aftermarket pipe. If your ski is an XP or SPX, then not so hard to break the 60 mark. The next problem is keeping hull planted in water. There is a ton of information covering modifications of the 787 engine. It was, in its day the hot ticket and tons of aftermarket support for racing. But that was over 20 years ago.

  5. #5
    Rhoup's Avatar
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    It's a XP


  6. #6
    Pacer's Avatar
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    What is your goal?

  7. #7
    Pacer's Avatar
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    It is impossible to run a 785 with the four strokes. If you mod it, and get 4 stroke competitive speed out of it, the engine won’t last as long as a four stroke. If you get the speed and reliability, you won’t have the fuel range of a four stroke.

  8. #8
    Fat Man, Little Boat Region8Ultra250X's Avatar
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    cut your losses and buy a 4 stroke. for what you'll spend to make the 787 to even come close you can pick up a used 4 stroke for around the same price.

  9. #9
    Rhoup's Avatar
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    Quote Originally Posted by Pacer View Post
    What is your goal?
    60 or close to it

  10. #10

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    Find a spec II Factory Pipe(brand name not oem) Put it on stock 785 in your 96 XP. Cut head to 155-160psi, .060-.065" squish, rejet the stock carbs with Prok F/A's, add 88/85 R&D nozzles with an X0 prop. It should run 62mph @ 7200 rpm on premium pump gas.

    There is enough posts covering all of this in very specific detail. The internet is your oyster.

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