Motorcycle Questions? Ask a Mechanic.
a couple possibilities come to mind.
Have you flooded it at all? If you flood the system, you can loose your compression and by adding oil you now helping the rings seal again.
and than you have to find out why it flooded.
If its not flooded than it could be a ring problem, and again the oil is heloing to seal the engine. in this case, the engine will have to be torn down.
I highly doubt that it is a valve problem as a burnt valve cannot be sealed by adding oil.
I hope this helps you in the correct direction.
Since this is a 4 stroke there is no reed system.
Ive had small engines flood to the point of no compression. i would try a little bit of oil to get the compression back , put a clean spark plug in and see if it starts. either way if its a valve or rings, than you will be rebuilding the engine.
compression is always mechanical. the oil is providing a temperary seal. the only way it will be simple is if you flooded it. than the oil will seal the rings again. the simple fix for that is to turn the engine over with the spark plug out and a bit of oil in the plug hole. Yes it will be a little messy but it will expell the excess oil out. than pop a clean plug back in it and try to start it. you will have to do this a few times as the plug will likley foul a few times. if its just flooded than it will start with a bit of efffort. if its a valve or ring problem , than its an engine teardown unfortunatly
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