A pedal-drive system for propelling multi-wheeled cycles includes two pedal level arms connected to a pair of two-bar linkages, which are drivingly attached to corresponding crank pins on each respective side of a common drive spindle, perpendicular to the cycle frame. The linkages rotate the said spindle per each pedal's downward stroke so that when one pedal arm is all the way down, the opposite pedal's crank pin is already beyond full up position, thus ensuring continuous rotation of the drive system. A sprocket on the spindle drives a chain, that drives a sprocket on a back wheel. For higher speeds, a typical bicycle multi-sprocket-cone and speed changing chain-derailleur may be incorporated. The pedal system may be used for small to large manually powered cycles, particularly scooters and bicycles, and may also include an auxiliary electric motor and battery for propulsion.