Abstract: A self-centering idler assembly is disclosed for a troughing conveyor belt. The idler assembly comprises a support frame and a gravity influenced pendulum cradle rocking supported on the frame for pivotable movement about a generally horizontal axis. A pair of rollers is rotatably mounted to the pendulum cradle along inclined axes above the horizontal axis. So constructed, bidirectional movements of a troughing conveyor belt supported upon the pair of rollers cause the cradle and inclined rollers to swing and bidirectionally train the belt.