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  1. #1
    Chrisrokc's Avatar
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    Piston Washing and other questions

    Hey whats up, long time since I last posted. Been busy with life and stuff, but I ride still when I go to the lake with friends or family.

    Haven't modded the gpr in a long time. Anyways this last weekend I had a small problem. The gpr was running good. 74 mph with a 1200 grate, just a thrown on FF plate, large nozzle, and r&d turning nozzle at 7160rpm. Ran like that for two days then on the end of the last day it was wanting to die on me like it had too much oil or too much gas. Low idle, would go if I gassed it, would go 72-74 mph if I hammered it on and off for a period of time. Sometimes it was just stuck at a low rpm even if I went WOT. No abnormal noises or clicks.

    I get home and I remove the plugs. One is really clean and the other two look really lean. Pressure was the same in all cylinders. Remove the head and the piston wash in two of the cylinders looks lean and the other looks good.

    Small note of possible importance is that it MAY have had too much oil in the premix. I am not for certain, but it was smoking a lot. I forgot if I had premixed the gas in the tank since I added 9 gallons and added an extra 28oz or so to be certain. Might have had 28oz of extra oil in the system.

    Anyways I attached pics. I think I want to up the compression since I have the head off and maybe I will send the cylinders out to have a more aggressive port done to them too.

    Thoughts?

    Thanks for the help guys.

    http://gallery.me.com/chrisrokc#1000...or=black&sel=7

    ^^ Pics!


  2. #2
    "just sayin".. jetdave56's Avatar
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    Chris did that spark plug pic #412 came out of cyl #1 (pic #413)..is that right?

  3. #3
    Chrisrokc's Avatar
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    Spark plug from 411 came out of cylinder 1 in 413. The spark plug from 412 came out of cylinder 2 or 3. The other spark plug looks identical.

  4. #4
    Happily Self-Employed WFO's Avatar
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    may be water intrusion... need more pics

    look for a chatter pattern on the cyl walls

  5. #5
    Chrisrokc's Avatar
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    I will post up some pics of the cylinder walls tonight. I looked for just a sec and there is some slight wear, but saw nothing significant on the first look.

  6. #6
    Happily Self-Employed WFO's Avatar
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    look for something like this
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  7. #7
    Chrisrokc's Avatar
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    I posted up some cylinder wall pictures. No evidence of chatter on the walls.

  8. #8
    Happily Self-Employed WFO's Avatar
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    top of #1 looks "cleaner" and lots of rust on the #1 front bolt holes and pipe mount bolts

    just saying

    look at your head gasket real good

  9. #9
    Chrisrokc's Avatar
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    You do have a point. I just now noticed that. Thanks for pointing it out. Taking pictures of the head gasket now. Is it possible I was ingesting water and didn't have any chatter?

  10. #10
    Happily Self-Employed WFO's Avatar
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    Quote Originally Posted by Chrisrokc View Post
    You do have a point. I just now noticed that. Thanks for pointing it out. Taking pictures of the head gasket now. Is it possible I was ingesting water and didn't have any chatter?
    tipically the water washes the oil away, and leaves a chatter... but since you were running extra oil...

    hard to say

    a couple spots on the edges of the #1 piston looked a little cooked from what I saw too

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