Patent ID: 7565891

Claim:
An engine for a vehicle comprising: a crankcase having a crank room for housing a crankshaft, the crankshaft extending in a crankshaft axis direction; and a transmission room formed rearward of the crank room and partitioned from the crank room by a partition wall, the transmission room housing a gear transmission having a gear train for backward movement and reserving oil of the engine, wherein the gear train for backward movement has a reverse drive gear provided on an input shaft of the gear transmission, a reverse driven gear provided on an output shaft of the gear transmission, and a reverse idle gear provided on an reverse idle shaft so as to be coupled with the reverse drive gear and reverse driven gear, wherein the input shaft and the reverse idle shaft are arranged so as to be separated into the upper side and the lower side of a reference line connecting an axis of the crankshaft and an axis of the output shaft, and wherein the reverse idle gear is arranged entirely in a space surrounded by the reverse drive gear, the reverse driven gear and the partition wall when viewed along the crankshaft axis direction.