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Thread: gpr upgrades

  1. #1

    Join Date
    Jun 2011
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    gpr upgrades

    i have started an upgrade project on my 1200 and i did a compression test on the motor and i got readings of 95psi on cyl #1, 110 psi on cyl#2 and 105 psi on cyl #3 i have been told that the comp on a stock gpr should be in the 110 to 130psi range. i pulled the cyl head off tonight and the gaskets look pretty good for a ski that is 12yr old. i can't see any cracks or any signs of corrosion on the gaskets , the pistons had hardly any carbon buildup on them though all three had some discoloration on the domes of the piston. i'm wondering if i should dig into the motor aliitle farther to try to find where the problem is but i am new to this stuff and really don't have alot of experience with engines and troubleshooting. can any one lend some advise as to what i should do or what i should be looking for?i have been planning on doing carb upgrades and pump upgrades on it this year. l i also removed the cat converter and installed the d-plate and sensor chip for the exhaust. rich.allen


  2. #2
    Ya Boy Trevor bajaeater's Avatar
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    did u ever think its just worn out pistons rings?

  3. #3
    Almost's Avatar
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    How many hours are on the ski? If you have more then 100 hours you might be due for a top end rebuild.

  4. #4
    I would tear it down and just go over everything before its to late and $$$$$$$$$

  5. #5

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    Jun 2011
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    according to the hour display the ski has about 80 hours on the motor , my brother-in-law was the original owner and i know that he has never had any engine work done, is it at all possible that the engine could lose comp back through the reed valves or maybe some kind of internal leak? the cylinder walls are clean on all three.what is involved with a top end rebuild. Thanks

  6. #6

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    Thanks for the advice

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