1 // New motors. Zero has continued to develop its motor technology, and this year debuts something called an IPM, for internal permanent magnet. In this and the previous Zero motors, the spinning part of the motor carries a series of permanent magnets. Attached to the case of the motor, which is finned for passive air cooling, is a series of coils that induce a magnetic field when power is applied. Before, the Zero motor had a series of magnets bonded to the circumference of the rotor, spinning with a minuscule air gap between them and the windings. Now the magnets are embedded into the rotor, which helps wick away heat and allow the motor to run cooler under all conditions. (A clever design of the rotor's facing surface helps move a small amount of air around inside the housing.) Last year's Zero S could be run into heat-management mode after several miles of high-speed running, which first results in a warning light and then a reduction in power to keep the motor from overheating. Supposedly, the 2016 Zeros all have much greater thermal headroom.