A transmission for a walk-behind wheeled vehicle, the transmission being of the type including at least one casing (2) housing a driver member (3), equipped with rotary drive motor means (4), a rotary driven member (5), two wheel drive shafts (6A, 6B) in alignment, two clutch mechanisms (8) each of which is disposed between the driven member (5) and a wheel drive shaft (6A； 6B), each clutch mechanism (8) being activated by the driven member (5) being driven in rotation forwards, and deactivatable by the wheel drive shaft (6A； 6B) with which it co-operates being driven in rotation forwards, when the speed of rotation of the wheel drive shaft (6A, 6B) is greater than the speed of rotation of the driven member (5). The rotary drive motor means (4) for driving the driver member (3) in rotation are motor means that can be controlled to rotate in two directions of rotation, and each clutch mechanism (8) is of the type that is deactivatable merely by the driven member (5) being driven in rotation in the backwards direction.
