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rmz 450 blowing oil out the crankcase

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so i took my bike out for the first time this year never made it around the track once and oil mixed with gas starting pouring out the crankcase vent. i checked the oil level it was good brought it home did compression test gauge said i 80psi anybody got any ideas on the problem??

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Blowby from leaky rings would be one thing that comes to mind.  I am not familiar with that engine and would ask you two questions:  What other vents are on the engine (higher ones especially)?  Had you checked compression previously,  and if so did you use the same method (did you block out the compression release etc)? 

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Compression release is also know as the auto decomp on the RMZ's. it is a weighted shaft on the exhaust cam, when the engine is tuned over, the weight swings outward and it moves the shaft which is an oblong shape and in turn, the oblong shape opens the exhaust valve which "releases compression" making it a lot easier to start. You will have to remove the valve cover to access it. It is possible I'm my experience, for some fuel to slip past the rings after it has sat for a long winter, usually a good heat cycle gets them working better again. However if the compression test was done properly, 80 PSI is pretty low. You say it was "pouring" out, how much are we talking? If the oil level was still fine after it was pouring out, is it possible you put too much oil in? Are you positive it was fuel in the oil?

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it wasnt leaking at idle when i gave it 3-4 good shots it started puking out it smelt like gas abit but i check the hose for the crankcase vent and right on top were it loops around the intake it had a big hole in it dont know if this would effect it??

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