Motorcycle Repair: reasons for oil in air filter, crankcase breather, airbox

Question
Besides having to much oil in the motor can you get oil in the air filter from a severe angle on the vehicle or dropping the bike?

Answer
Sure. If the bike is a 4-stroke it has a crankcase breather and tube that usually connects to the airbox. If the bike has been laid down there is a good chance of oil running into this tube and getting into the airbox.

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