Abstract: A transmission includes a body, a transferring gear set, a driving gear set, a reversible gear set, a unidirectional gear set, a wedge and a switcher. The body is mounted on a wheel. The transferring gear set includes a driving shaft and a transferring gear. The driving gear set includes a wheel hub and a driving gear. The reversible gear set includes a reversible sleeve and a reversible gear. The unidirectional gear set includes a follower gear, a unidirectional clutch and a unidirectional sleeve. The unidirectional clutch engages the reversible sleeve to the follower gear when the reversible sleeve is rotated in a first direction and disengages the reversible sleeve from the follower gear when the reversible sleeve is rotated in a second direction. The switcher moves the wedge to engage the recesses of the unidirectional sleeve and the reversible sleeve.

Abstract: A wheeled vehicle includes a main frame, a drive axle rotatably mounted on the main frame, a chainwheel secured on the drive axle, an eccentric shaft secured on the drive axle, a support post mounted on the main frame, a rocking arm pivotally mounted on the support post, and a linking member having an upper end pivotally connected with the rocking arm to move with the rocking arm and a lower end pivotally connected with the eccentric shaft to move the eccentric shaft. The rocking arm has two opposite sides each provided with a pedal. Thus, the wheeled vehicle is driven to move forward by stepping the pedals of the rocking arm upward and downward in a reciprocal manner to provide a different pedalling manner.