An output shaft (12) comprises an output shaft main body (12A) connected to a variable transmission unit (U) and an output shaft downstream portion (12B) downstream in the power transmission direction from the output shaft main body (A), and because a dog clutch (55) is arranged between the output shaft main body (12A) and the output shaft downstream portion (12B), when the output shaft main body (12A) becomes fixed and can no longer rotate, the fixed output shaft main body (12A) is prevented from locking the drive wheel (W) by the dog clutch (55) disengaging and cutting the output shaft downstream portion (12B) off from the output shaft main body (12A), allowing the vehicle to be safely driven to a repair shop without trouble.