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  1. #31
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    Quote Originally Posted by rotaryboots View Post
    How is that stroke measured? From piston head to?
    Stroke is just the measurement from bottom dead center to top dead center, you drop a thin 12" rod into the plug hole and rotate the engine by hand until its the farthest into the plug hole as it gets.

    Mark that point with a sharpie and then rotate the engine over in the same direction until it reachest the tallest point and make another mark.

    Yank the stick out and measure the distance, thats your stroke.

    Sean

  2. #32
    Replacement ECM installed, no change...

  3. #33
    Probably going to pull the case cover and check the crank sensor wheel.

    Even if it was a 1200, a 1500 ECU would run rich but still rev normally? I'll be checking the stroke later today.

  4. #34
    If I give it quick revs it will bounce off 6K rpms then settle back on 4-4500rpms and bounce between 4&6 with a backfire each time.
    This last test blew the crossover pipe off the first water box outlet.
    Thought maybe I had a plugged secondary water box and ran an exhaust hose outside the Hull and started it; was louder but no change.

    I'm thinking timing and/or a lean condition.

    Ive read there are different cam sensor lobes between the years, but in the thread I read, it wouldn't run unless they matched the timing for that engine.
    Last edited by rotaryboots; 08-17-2019 at 03:41 PM.

  5. #35
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    The cam timing needs to be checked, the only lobe difference was if you had swapped zx12r cams in and only if it was a 2000 year model cam.

    Sean

  6. #36
    Checked it once, but I'll do it again with the crank sensor cover removed and take pics.

    The endcap that has the one sensor love on it varied between two years according to this thread:
    http://greenhulk.net/forums/showthre...=271340&page=4

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  8. #37
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    Quote Originally Posted by rotaryboots View Post
    Checked it once, but I'll do it again with the crank sensor cover removed and take pics.

    The endcap that has the one sensor love on it varied between two years according to this thread:
    http://greenhulk.net/forums/showthre...=271340&page=4
    Weird, never seen that before. The really odd part is that you can run a 2013 tune on a 05-13 engine, I do that when I flash the ecus for the new temp sensors.

    Sean


  9. #38

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    I see you found the post I was referring to. Hope this helps you. Please keep us posted.

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