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  1. #1
    SideFX's Avatar
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    Question 140/139 cyl pressure..fair, good,?

    Hi guys, recently took a reading and got 140 and 139 psi compression on the cylinders. (650)
    Thing is I'm not sure what the spec is or what a low/good reading would be.
    If someone knows, please pass it this way .)

    Thank you.
    Peter


  2. #2
    IF ITS SUNDAY DALE LETS RIDE EL bicho MMP's Avatar
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    good very good

  3. #3
    Water Bum Rodneyae's Avatar
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    Good numbers.

  4. #4
    SideFX's Avatar
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    Quote Originally Posted by Rodneyae View Post
    Good numbers.
    Thanks for the reply guys, but still curious on what they would be if it was a fresh build. 150? 147? 500?

  5. #5
    96XPSS's Avatar
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    Quote Originally Posted by SideFX View Post
    Thanks for the reply guys, but still curious on what they would be if it was a fresh build. 150? 147? 500?
    A fresh build would be less compression, because the rings hasn't seated yet...

    There is too much variation in gauges to worry about 5 lbs less on your gauge. You probably have excellent sealing, as excellent is around 145 lbs stock.

  6. #6
    SideFX's Avatar
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    Quote Originally Posted by 96XPSS View Post
    A fresh build would be less compression, because the rings hasn't seated yet...

    There is too much variation in gauges to worry about 5 lbs less on your gauge. You probably have excellent sealing, as excellent is around 145 lbs stock.
    Thanks for that information 96XPSS. Reason being for my question was that since she's a cougar, I wanted to have a benchmark to measure from and keep record of since the craft came without a recorded history.

    Thanks again to everyone

  7. #7
    96XPSS's Avatar
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    Gotcha. You'll get many, many hours before the compression will start to drop. Happy riding...

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