Answer : There are two types of controls of Achiever Coaxial motor system. They are Throttle controlled and Pedal Assist. Throttle controlled means you use a throttle to control power and speed. To get started, simply twist the throttle to accelerate and hold it to maintain speed. Pedal Assist means that power is applied automatically. Once you start pedaling, a torque sensor picks up your movement and power integrates seamlessly while you ride. Just pedal and go. Once you quit pedaling, the power is deactivated and you need to pedal again to re-activate pedal assistance. For people who prefer full control, a throttle is a nice option since it operates just like a motorcycle. But if you're looking for simplified operation, pedal assist is great because it does all the work automatically. Keep in mind: you have to pedal for power to be applied with pedal assist. With a throttle, no pedaling is required at all. Please Note: PedElec including a throttle may be illegal in some countries.