Provided is an apparatus for supplying lubricant to a timing chain installed in an engine, the apparatus including an injection hole configured for injecting lubricant from an oil pump, and an inner cover having a guide groove configured to receive lubricant injected from the injection hole and guide the lubricant toward a engagement place between the timing chain and a sprocket, wherein the inner cover has a guide groove provided at a position facing an injection hole of a counter surface portion that is spaced apart from a cylinder block and faces the guide groove.

A front cover (7) is made of a resin material such as a synthetic resin and is attached to an internal combustion engine body so as to cover the front surface of the internal combustion engine body. The front cover (7) is formed with a mounting part (21) made of a resin material and protruding to the forward side of an internal combustion engine. The mounting part (21) is formed in an elongated hollow shape along the cylinder axial direction of the internal combustion engine. The mounting part (21) is equipped with a vehicle body attachment part (23) for attaching the internal combustion engine to a vehicle body. The vehicle body attachment part (23) is formed integrally with the mounting part (21). It is thereby possible to reduce the weight and number of components of the internal combustion engine.

A chain cover includes a first member, which is made of a hard plastic, and a second member, which is made of a material different from the hard plastic. The first member includes a back face, which faces an engine main body. The second member is joined to the first member. Only the back face of the first member includes a groove, which receives a seal member. The seal member provides a seal between the first member and the engine main body.

To provide a chain guide assembly frame capable of efficiently collecting the oil that adhered to various parts of the chain guide assembly, and guiding the collected oil to predetermined locations, to allow efficient use of oil, with a simple structure. The chain guide assembly frame includes driven sprocket holding portions, a fixed chain guide, and a pivoting chain guide holding portion on a main body. A drive sprocket holding portion is provided at a position lower than the driven sprocket holding portions. The main body includes a concave and/or convex oil passage that extends from an upper part toward a lower part to guide the oil toward above the drive sprocket holding portion.

An internal combustion engine 31 for a motorcycle includes a supercharger 63 arranged above a crankcase 81 positioned below a front cylinder head 92 of a front bank 31A and a rear cylinder head 97 of a rear bank 31B. In the internal combustion engine 31 for the motorcycle, the crankcase 81 is covered with a case cover 116 from the outside in a vehicle width direction, and the supercharger 63 is supported by a supercharger supporting portion 116a provided above the case cover 116.

An internal combustion engine includes a cylinder head, a crankshaft, intake and exhaust camshafts, first and second chain covers, a chain, and a fastening bolt. The first chain cover having a cutout includes a first flange positioned at a specific edge portion of the cutout, which is positioned between the crankshaft and the camshafts, and a first boss through which a shaft portion of the fastening bolt is passed. The cylinder head includes a second flange, and a second boss into which the shaft portion is inserted, and which is disposed coaxially with the first boss. The liquid gasket is held between the second flange and the first flange. 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.

An engine cover system, includes a metal engine cover having an opening that receives a radial shaft seal including a seal lip adapted to engage a shaft, and a plastic film adhered to the metal cover over top of the radial shaft seal.

A chain cover includes a first member, which is made of a hard plastic, and a second member, which is made of a material different from the hard plastic. The first member is formed by insert molding with the second member as an insert. A first joint surface is formed in a peripheral portion around an insertion hole. The first joint surface is joined to the first member. The first joint surface includes a first joint portion, which includes a lattice-shaped recess portion, and a second joint portion, which includes grooves. The grooves extend in a direction in which the peripheral portion extends, while being arranged in an intersecting direction, which intersects with the extending direction. The second joint portion is provided to be closer to a space adjacent to the peripheral portion than the first joint portion. - - -

A front cover (7) is made of a resin material such as a synthetic resin and is attached to an internal combustion engine body so as to cover the front surface of the internal combustion engine body. The front cover (7) is formed with a mounting part (21) made of a resin material and protruding to the forward side of an internal combustion engine. The mounting part (21) is formed in an elongated hollow shape along the cylinder axial direction of the internal combustion engine. The mounting part (21) is equipped with a vehicle body attachment part (23) for attaching the internal combustion engine to a vehicle body. The vehicle body attachment part (23) is formed integrally with the mounting part (21). It is thereby possible to reduce the weight and number of components of the internal combustion engine.

A chain cover includes a first member, which is made of a hard plastic, and a second member, which is made of a material different from the hard plastic. The first member includes a back face, which faces an engine main body. The second member is joined to the first member. Only the back face of the first member includes a groove, which receives a seal member. The seal member provides a seal between the first member and the engine main body.