Steering: Pepin knew the Lithium Hawk would have to be registered as a motorcycle, so he opted for handlebars instead of a rack-and-pinion system; he was worried that the regulatory authorities might not approve a steering wheel. The handlebars he used initially were difficult to turn at low speeds, so he had to entirely rebuild the front of the chassis. (When he had the vehicle inspected, the regulators said they would have been fine with a steering wheel.)
Brakes: The vehicle has hydraulic brakes, but Pepin mainly relies on a regenerative braking system to stop. When he wants to accelerate, he twists the handlebar throttle toward himself, and to slow down, he turns it away. This sends a signal to the motor controller to slow the rear wheel. The Lithium Hawk’s motor behaves as a generator, and the controller captures the excess energy that’s produced and routes it to the cells, extending the vehicle’s range.
Performance: Pepin has driven more than 2,000 miles in the Lithium Hawk, and he says it out-accelerates practically every other vehicle on the road. He can jump from 45 mph to nearly 70 in about two seconds. At this point he won’t estimate the actual range of the vehicle, in part because it’s a skeleton. Had he decided to enclose the Hawk in an aerodynamic shell as he initially planned, the range would increase significantly at highway speeds.single page
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.