Patent ID: 7621248

Claim:
An internal combustion engine, comprising: a combustion chamber formed between a cylinder block and a cylinder head opposite to a top portion of a piston slidably fitted in the cylinder block; and an intake path extending from an inlet pipe separately or integrally connected to the cylinder head and communicating with an intake valve port that opens to a top surface of the combustion chamber to be opened/closed with an intake valve; wherein the intake path is provided with a pair of throttle portions arranged with an interval in an air flow direction of the intake path and an expanding portion positioned between the throttle portions, wherein a throttle body is arranged upstream of the pair of throttle portions, and wherein the throttle portions are provided to a bent portion of the intake path formed in a substantially U-shape in section as viewed in a projected plan orthogonal to an axial line of a crank shaft and parallel to a cylinder axial line.