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  1. #1

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    what caused this ???

    what do you think caused this its from a 94 slt750 that was rebuilt over 5-8yrs ago the compression was 110 / 110 / 30(mag cyl.)

    and the head... can it be reused??
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  2. #2
    Moderator beerdart's Avatar
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    Looks like water intrusion.

  3. #3

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    whats up beerdart... that could be it.. on the head it feels like a chunk of metal or something is sticking up not sure though

  4. #4
    Watcon's Avatar
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    Whats wrong.

    You need a new crankshaft!

  5. #5

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    Quote Originally Posted by watcon View Post
    you need a new crankshaft!

    hey watcon whats brings you to that conclusion

  6. #6
    Race, wreck, repeat delagem's Avatar
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    Something metal went through that combustion chamber. Randy is undoubtedly thinking it's one of your crankshaft bearings coming apart.

    I had a similar problem a few years ago, I posted pics, took the head to Sharps Marine, several local shops, but the only person who diagnosed it correctly was Randy. He did it by looking at one of my spark plugs, saw fragments of the crank thrust washer, if I remember correctly.

    Interestingly, you've got low compression. I didn't have that. So is it possible your ring broke apart, caused the damage on its way out, and maybe your crank is fine?

    Heads for these models are cheap to free, I wouldn't reuse it. But when my 650 was going thru this same phase, I sanded the sharp edges and reused the head several times.

  7. #7

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    thanks i will pull the cylinder and check the rings if they are broke then i might just roll- da- dice..

  8. #8
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    Quote Originally Posted by nick34 View Post
    hey watcon whats brings you to that conclusion
    Nick,Randy came to that conclusion from many years of being one of the top Professional tuners in the country. Don't roll the Dice. Pull the engine and tear it down and check it all out. Putting the time to just change a cyl, piston and still having problems,will cost more in the long run then doing it right the first time.

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