This disclosure describes a configuration of an unmanned aerial vehicle (“UAV”) that will facilitate extended flight duration. The UAV may have any number of lifting motors. For example, the UAV may include four lifting motors (also known as a quad-copter), eight lifting motors (also known as an octo-copter), etc. Likewise, to improve the efficiency of horizontal flight, the UAV also includes a pivot assembly that may rotate about an axis from a lifting position to a thrusting position. The pivot assembly may include two or more offset motors that generate a differential force that will cause the pivot assembly to rotate between the lifting position and the thrusting position without the need for any additional motors or gears.