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 quantitative one-way oil gas lubricant system and a method for a 4-stroke engine, including a preceding stage quantitative oil intake orifice that is connected to a lubricant case on a wall of a crankcase of the 4-stroke engine, and a final stage quantitative airflow orifice disposed at a cylinder cover of the 4-stroke engine, are provided. A diameter of the preceding stage quantitative oil intake orifice D.sub.1 and a diameter of the final stage quantitative airflow orifice satisfy an equation: D.sub.1/D.sub.3=0.8-1.5, wherein a one-way connected oil gas lubricant channel is disposed between the preceding stage quantitative oil intake orifice and the final stage quantitative airflow orifice. A lubricant oil sucked from the preceding quantitative oil intake orifice by the crankcase flows along the oil gas lubricant channel and lubricates the engine parts that the channel passes through in turns. Finally, a minute quantity of waste oil gas that flows out from the final stage quantitative airflow orifice is introduced into a cylinder of the 4-stroke engine and is to be burned completely. The supply quantity of the lubricant oil may be controlled, and no extra lubricant oil gas may flow out from the final stage quantitative airflow orifice, therefore, the quantitative and one-way lubricating is realized.

A cam shaft drive device includes a chain, a guide lever, a chain chamber, which is provided in a cylinder head, a support bolt, which pivotably supports the guide lever, the support bolt including a head portion, a male screw portion, and a shaft portion, which is inserted through the support hole of the guide lever, an insertion hole, which is through which the support bolt is inserted, and a female screw hole, which is provided in the rear wall and into which the male screw portion is screwed, wherein a length from a rear end to a front end of the shaft portion is longer than an axial distance from a front end of the support hole to a front end of the insertion hole in a state where the guide lever abuts on the rear wall.

A thermoplastic engine cover for an internal combustion engine has a plurality of mounting holes for mounting the thermoplastic engine cover to an internal combustion engine. At least two datum locator formed on or arranged on the thermoplastic engine cover. At least one through opening configured to receive a rotatable shaft of the internal combustion engine. The at least one through opening has an internal diameter sized to provide an annular clearance gap between the seal carrier and an adjacent circumferential wall of the at least one through opening, to allow final positioning of the seal in the annular clearance gap to a final position in which the seal and seal carrier are positioned in a dimensionally correct position relative to the at least two datum locators. The seal carrier is then welded to the thermoplastic engine cover.

A heat insulating structure of an internal combustion engine (engine 1) includes a cylinder-head-side heat insulating cover (30) and a cylinder-block-side heat insulating cover (40). Each of the first side walls (32) of the cylinder-head-side heat insulating cover (30) is disposed outwardly of, and is spaced apart from, a corresponding one of the second side walls (43) of the cylinder-block-side heat insulating cover (40) in the width direction of the vehicle. The lower edge of each of the first side walls (32) is positioned below the upper edge of the corresponding one of the second side walls (43) to overlap with the corresponding one of the second side walls (43) when viewed from the side of the vehicle.

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.

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.

Methods and systems are provided for a vehicle component cover. In one example, a vehicle component cover may be adapted to conceal vehicle components within an engine compartment, and the cover may include an embedded support structure having a plurality of notched sections. The support structure may deform at the plurality of notched sections to increase an energy absorption characteristic of the vehicle component cover.

In an oil filter attaching structure for a vehicle-mounted internal combustion engine, an oil filter of the engine is installed in a filter case integrally formed with a crankcase cover of a crankcase. The crankcase cover is mounted on a side surface of the crankcase so as to cover an end of a crankshaft supported by the crankcase to extend in vehicle widthwise directions. An internal combustion engine accessory and a transmission clutch device are disposed inside of the crankcase cover in respective positions forward and rearward of the crankshaft. The oil filter and an oil supply port are disposed inside of the crankcase cover in respective positions upward and downward of the crankshaft. The oil filter attaching structure efficiently utilizes the space for making itself smaller in size and for better maintainability.

Methods and systems are provided for a vehicle component cover. In one example, a vehicle component cover may be adapted to conceal vehicle components within an engine compartment, and the cover may include an embedded support structure having a plurality of lock orifices positioned to align with a plurality of openings of a solid encasement. The plurality of lock orifices are adapted to couple in locking engagement with a plurality of extensions of an emblem of the cover.