Abstract: A training idler for guiding a travelling conveyor belt so that the belt follows a central path. The training idler includes an axle adapted to be mounted to a conveyor support frame, a steering roller rotatably mounted on the axle and adapted to be aligned generally transverse to a conveyor belt which will ride thereon, and a pivot connecting the roller to the axle, the pivot defining a generally perpendicular pivot axis about which the steering roller is able to pivot. The steering roller has an outer peripheral surface of generally right circular cylindrical form and has a central region and opposite edge regions, the edge regions having a peripheral circumference which is either greater than or less than the peripheral circumference of the central region.