Patent attributes
A powertrain assembly having an improved engine configuration includes an engine and a transmission incorporated in a crankcase of the engine. The engine also comprises an oil pump and a water pump. The transmission is a cartridge-type shift drum transmission, which can be attached to or detached from a transmission attachment face which is a side face of the crankcase. The oil pump and the transmission attachment face are arranged in substantially non-overlapping relation in the side view of the engine. The water pump shaft is substantially coaxial with the oil pump shaft, and the water pump is positioned below a drive sprocket on the transmission countershaft so as to be overlapping while eliminating interference between them, allowing a close arrangement of components.
