Question about Yamaha YZ 250 Motorcycles

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94 Yz 250 Runs Strong and Fast after it warms up a little, smoky and boggy when it first starts. Had Motor checked by Mechanic, he said has slight loss of compression but other than that strong engine. My issue is that after it has been ridden for 20- 30 minutes and I stop in gear(With Clutch in) It makes a Pinging sound until it gets back to Idle. If I put it N it seems to stop right away. It almost seems like the engine is dieseling, but I am concerned it may be in the bottom end i.e the crank bearing. The Bike does seem to blow more oil than most,I think last guy ran at 40 to 1 I have repacked pipe and changed fuel but it seems to be pushing allot of oil out of the pipe, it runs down the pipe and onto swing arm... not sure if this a symptom or not.

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Probably could use a valve job

Posted on Jan 30, 2010

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Posted on Jan 02, 2017

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2 Answers

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1 Answer

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Oct 09, 2009 | 2003 Yamaha YZ 250

1 Answer

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1 Answer

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