Internal combustion engine

摘要

Disclosed herein is an internal combustion engine (E) having a crankcase (335) in which a crankshaft (336) and a transmission (M) are accommodated, the transmission (M) having a plurality of gears for shifting, an input shaft for inputting a rotational drive force from the crankshaft (336), and an output shaft to which the rotational drive force is transmitted from the input shaft through the gears, the rotational drive force being further transmitted from the output shaft to a drive wheel. The internal combustion engine (E) includes rotation detecting devices (401 and 402) for respectively detecting the rotational speeds of the gears (49c and 49d) included in the transmission (M), the rotation detecting devices (401 and 402) respectively having detecting portions (401a and 402a) opposed to the gears (49c and 49d) rotating with the rotation of the input shaft (28) and positioned in the axial direction of the transmission (M).