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Low compression good leakdown?

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35-40psi compression but the leakdown held fine. Im thinking bent conrod? Any input? You can hear the engine cranking too quickly it will not start. Sounds fine cranking no strange noises. 

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Well yes, to have compression that low and no leak down possibly the piston is not going to the top of the bore.  More likely is the cam timing is off and a valve is closing late or one of the tests is inaccurate.

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a friends was riding it said oil started leaking everywhere (oil all over the chain & rear wheel and everywhere) i dont see any holes in the case. How would I diagnose a bad decompressor? I also thought timing may have jumped, ill have to give a look at that also. 

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Why is it that all the relevant information is never given up front.  We don't even know what motorcycle we are diagnosing.  Oil all over the chain? An E model? or S with the oil separator removed? or counter shaft seal or nut or ????.

A auto decompressor that will not disengage will not lower the compression to under 100 psi.

I'm going to speculate a serious ring problem and the leak down test is wrong.  Maybe a counter shaft seal failure that pumped all the oil out and now seeing the result of no oil.

Question - is there any oil in the motor?  If no oil on the dip stick, drain and measure the oil that comes out of the frame and motor sump.

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