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  1. #1

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    compression test

    I did a compression test on my 2002 GTXdi both cylinders are 105 lbs. can someone tell me what is the range where they should be could not find in shop manual.


  2. #2
    PEST!'s Avatar
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    Thats because compression is to subjective. Many things can alter it. Leakdown is better but they dont have it either. It sounds low. They are the same so unless it was down on power or hard t start I would do nothing

  3. #3

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    compression

    I was just curious thinking of getting something new for the wife, like to know what the general condition of the engine is. I've had no problems with the ski starts right up and runs great.

  4. #4
    King_Of_Fun's Avatar
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    It seems like the the formula was: compression ratio x 14.7 psi (at sea level. So an engine with a 8.4:1 compression ratio would be around 125 psi at sea level. Although, the biggest factor is having an accurate compression guage, and testing the compression with a warm engine and throttle wide open... Ron

  5. #5

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    compression

    I'm not sure that is right I beleive on that engine the compression is only 6-1 which would make the compression 88.2 at best and if my gauge is right I had 105 in both cylinders.

  6. #6
    SeaGoat's Avatar
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    Don't believe I've ever heard of an engine with only 6-1 cr. It's gotta be higher then that.

  7. #7
    GTXX's Avatar
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    it's very difficult to determine wha the actual mechanical compression ratio on a 2 stroke. if they are both the same and it runs good, don't worry about it.

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