Abstract: A powered scale model vehicle having a transmission with a forward gear and a reverse gear. The transmission is shiftable between the forward gear and the reverse gear. The vehicle has a radio control receiver, a sensor and a microcontroller. The receiver is adapted to output a throttle signal and a shift signal to the microcontroller. The sensor is adapted to obtain a vehicle speed measurement. The microcontroller is electrically coupled to the receiver and the sensor. The microcontroller may be adapted to control a timing and execution of a forward/reverse shift on the transmission based on at least the vehicle speed measurement, the throttle signal, and the shift signal, for example.

Abstract: A forward/reverse transmission, shiftable under servo-control, includes a movable clutch bell and a free-wheeling, one-way centrifugal lock-out clutch that permits a gear change from forward to reverse or reverse to forward only while the engine is operating at or below idle speed. The centrifugal lock-out clutch includes a spring-loaded pawl which is yieldably biased by a compression spring and held in a non-interfering, shiftable position when the engine is being operated at or below idle speed. As the engine rpm increases above idle, the centripetal acceleration force overcomes the bias force of the compression spring and the pawl is extended radially outwardly for engagement with a torque transfer pin. In the radially extended position, the pawl is disposed for interference contact against the clutch bell housing, thus preventing clutch engagement/disengagement.

Abstract: A forward/reverse transmission, shiftable under servo-control, includes a movable clutch bell and a free-wheeling, one-way centrifugal lock-out clutch that permits a gear change from forward to reverse or reverse to forward only while the engine is operating at or below idle speed. The centrifugal lock-out clutch includes a spring-loaded pawl which is yieldably biased by a compression spring and held in a non-interfering, shiftable position when the engine is being operated at or below idle speed. As the engine rpm increases above idle, the centripetal acceleration force overcomes the bias force of the compression spring and the pawl is extended radially outwardly for engagement with a torque transfer pin. In the radially extended position, the pawl is disposed for interference contact against the clutch bell housing, thus preventing clutch engagement/disengagement.

Abstract: This invention provides and improved apparatus and an improved method of adjusting the tractive torque at the driven wheels of a scale model vehicle employing an enclosed friction driven differential. The invention's improvements allow this adjustment to be accomplished without disassembly of the driven axles, or removing any member of the differential's enclosure to gain access to the internal adjusting components.