Internal Combustion Engine

An internal combustion engine comprising:

• a cylinder head;
• a crankshaft;
• an intake camshaft and an exhaust camshaft disposed in the cylinder head;
• a first chain cover disposed in contact with the cylinder head;
• a second chain cover disposed in contact with the first chain cover;
• a chain looped over the crankshaft, the intake camshaft, and the exhaust camshaft, the chain being disposed in a space defined by the first chain cover and the second chain cover;
• and
• a fastening bolt that fastens the first chain cover and the second chain cover to the cylinder head, wherein
• the first chain cover includes an edge portion defining a cutout such that the intake camshaft and the exhaust camshaft are positioned in a space in the cutout,
• a portion of a peripheral edge portion of the cutout is a specific edge portion positioned between the crankshaft and the intake and exhaust camshafts,
• the first chain cover includes a first flange positioned at the specific edge portion and a first boss through which a shaft portion of the fastening bolt is passed, the first boss being disposed adjacent to the first flange, and the first boss being located on the crankshaft side with respect to the first flange,
• the cylinder head includes a second flange that holds a liquid gasket in cooperation with the first flange in such a manner that the liquid gasket is held between the second flange and the first flange, and a second boss into which the shaft portion of the fastening bolt is inserted, the second boss being disposed coaxially with the first boss, and
• a groove is provided in at least one of a position between the first flange and the first boss of the first chain cover and a position between the second flange and the second boss of the cylinder head.