Abstract: A wheeled vehicle powered by its rider to move about on three wheels. It includes a single front wheel and preferably a pair of rear wheels mounted to an elongated frame. The rear wheels are mounted to the frame by a carriage assembly that facilitates pivotal movement of the rear wheels about two axes. The first axis is a steering axis and the second is a steering control axis. The angle of the steering axis may be varied about the steering control axis. Through this arrangement, the rider is able to selectively control the steering response of the vehicle. If he shifts the steering axis to a position parallel with the ground surface he may maneuver the vehicle in wide sweeping high speed curves by leaning as does a bicyclist. The rear wheels merely track behind the front wheel and the frame tilts about the steering axis. If the rider shifts the steering axis to a position nearly perpendicular to the ground, he may negotiate short radius low speed turns.