Patent ID: 7159582

Claim:
In an internal combustion engine configured to be mounted to a vehicle having a drive clutch, wherein the engine comprises a crankcase and an air-intake system, the improvement comprising a blowby gas control system for the engine, said blowby gas control system comprising: a fresh air introducing channel for introducing fresh air into the crankcase; a blowby gas return channel for returning blowby gas from the crankcase to the air-intake system; a blowby control valve provided in the fresh air introducing channel or the blowby gas returning channel for selectively restricting gas flow through the channel, the blowby control valve having an opened state and a closed state; and a controller for controlling operation of the blowby control valve, said controller being in electronic communication with the blowby control valve; wherein the controller is programmed to switch the blowby control valve from the closed state to the opened state, with the drive clutch engaged, when the vehicle starts traveling.