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  1. #1
    crxski's Avatar
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    Stock compression question 787

    Just want to comfrim this, I'm getting 170psi per on each, stock stock 35 hours...? high?

    I checked it cold, I didn't start it for like 15 secs then shut it off and check.

    Then I checked it after a quick 10 sec warm up pulled the plugs check it 160 in each. I was taught to check it after a quick warm up like this.

    Is my gauge off? sounds like it to me?

    I'm going to get the head milled tomorow and starting to think the compression is alittle high?


  2. #2
    Should be 145 - 150. Perhaps some oil is leaking in there.

  3. #3
    crxski's Avatar
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    Quote Originally Posted by Seapoo View Post
    Should be 145 - 150. Perhaps some oil is leaking in there.
    maybe its been sitting for 2 weeks now, I tested it cold first, then started it up for 10sec then tested it again and it went down so would make sense. I tend to choke it out sometimes if I'm not going to ride it for a while.

  4. #4
    Next time start it up for awhille, drive around., park it and test compression with throttle wide open. Post your results.

  5. #5
    crxski's Avatar
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    Oh and I did both tests with throttle wide open

    I think I'll hook the hose up now and let it run for a little bit and recheck it.

    Oh one more question...

    Is there anything I should be asking or requiring to be done when getting the head milled?

  6. #6
    Why mill the head?

  7. #7

    milling

    milling your head will increase your compression as well. the only time you should mill your head is if it is warped or if you are doing high performance work. higher compression makes it harder to tune properly affects performance.

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