Abstract: A bidirectional propulsion caster assembly is disclosed for enabling a rider to generate bi-directional motion from a ride-on device. A mounting bracket is attachable to the bottom of the device and defines a pivot axis extending in a generally transverse direction across the bottom of the device. A rocker bracket and caster shaft having a caster shaft axis are attached to the mounting bracket and pivot about the pivot axis along an arc between first and second positions. A wheel bracket is mounted to and rotates about the caster shaft. A wheel is mounted to the wheel bracket for rotation about a wheel axis angularly offset from the caster shaft axis. One or more changeable pivot stops may be attached to the rocker bracket or the mounting bracket and effective to further define the available arc of rotation.