Abstract: A cam drive gear for an engine is described where the distance between the axes of a crankshaft and an idle shaft bearing an idle gear thereon can be made smaller, thereby contributing to a reduction in the size of the engine. In addition, a valve-operating system drive gear for an engine is also described where it is possible to restrain a cam chain from chattering at its portion wrapped around a drive sprocket.

Abstract: A V-type, multicylinder internal combustion engine with multiple isolated crank chambers formed by partitioning a space inside of a crankcase with multiple support walls for supporting a crankshaft, and multiple oil outlet holes, respectively communicating with the isolated crank chambers to separately discharge oil from the multiple isolated crank chambers, uses a single scavenging pump to discharge the oil from the isolated crank chambers rather than connecting multiple scavenging pumps, respectively, to the oil outlet holes. The engine includes an oil collecting pan mounted on a bottom wall of a crank chamber covering the multiple oil outlet holes respectively communicating with the multiple isolated crank chambers for collecting the oil passed through the oil outlet holes. The oil collecting pan has an oil reservoir with an oil outlet opening, and a single scavenging pump for drawing the oil stored in the oil collecting pan through the oil outlet opening.

Abstract: A cam drive gear for an engine is described where the distance between the axes of a crankshaft and an idle shaft bearing an idle gear thereon can be made smaller, thereby contributing to a reduction in the size of the engine. In addition, a valve-operating system drive gear for an engine is also described where it is possible to restrain a cam chain from chattering at its portion wrapped around a drive sprocket.

Abstract: A V-type, multicylinder internal combustion engine with multiple isolated crank chambers formed by partitioning a space inside of a crankcase with multiple support walls for supporting a crankshaft, and multiple oil outlet holes, respectively communicating with the isolated crank chambers to separately discharge oil from the multiple isolated crank chambers, uses a single scavenging pump to discharge the oil from the isolated crank chambers rather than connecting multiple scavenging pumps, respectively, to the oil outlet holes. The engine includes an oil collecting pan mounted on a bottom wall of a crank chamber covering the multiple oil outlet holes respectively communicating with the multiple isolated crank chambers for collecting the oil passed through the oil outlet holes. The oil collecting pan has an oil reservoir with an oil outlet opening, and a single scavenging pump for drawing the oil stored in the oil collecting pan through the oil outlet opening.

Abstract: A lubricating oil feeding apparatus of an internal combustion engine can adjust an amount of oil fed to each bearing and provides for a reduced number of parts for a shaft portion structure of a starter driven gear. In the engine, a balancer shaft is synchronously rotated with a crankshaft. The crankshaft and the balancer shaft are rotatably supported on a split surface of a crankcase by plain bearings. Parallel oil passages communicate with oil holes provided in the plain bearings for exclusively feeding lubricating oil to at least the crankshaft and the balancer shaft. The opening areas of the oil holes provided in the plain bearings of the balancer shaft are smaller than the oil holes provided in the plain bearings of the crankshaft. An outer portion of a starter one-way clutch can also be integrally fitted on a rotor. A driven gear of the starter is connected to a starter drive gear of a starter motor by intermediate gears. The diameter D.sub.