Sanyo Eneloop Electric Bicycle Bike CY-SPA600NA Brake Charge System: Depressing the rear brake lever transforms the motor into a generator that is capable of charging the battery. This creates energy whenever the brakes are applied while riding. Auto Mode: In auto mode, the bike automatically adjusts to the environment's riding conditions, whether it be a flat surface, uphill or downhill. Auto Mode allows you to increase your riding distance up to 1.8 times longer. Power-Up Mode: Ride More Comfortably with Powerful Assistance The built-in Power-up mode increases the output ratio of the power assistance motor, allowing you to comfortably ride uphill with very little energy expended pedaling. Two-Wheel Drive: A Smooth Start The unique SANYO drive configuration makes it easy to ride in confidence. The front wheel is motor-driven and the rear wheel depends on pedaling force, which prevents wobbling starts and grips the road.