Patent ID: 6941908

Claim:
An internal combustion engine, comprising: a cylinder head; an intake valve slidably supported by said cylinder head; an exhaust valve slidably supported by said cylinder head; a first clearance adjusting mechanism for actuating said intake valve, said first clearance adjusting mechanism, setting a first valve clearance when the engine is in a first state, where both said intake valve and said cylinder head are in a cold state, and changing a second valve clearance, when the engine is in a second state, where the engine transits from the cold state to a hot state, after a cold start of the engine, such that an open timing of said intake valve is advanced and a close timing of said intake valve is retarded; and a second clearance adjusting mechanism for actuating said exhaust valve, said second clearance adjusting mechanism opens and closes said exhaust valve at fixed predetermined timings regardless of a temperature of said exhaust valve and said cylinder head.