Self-positioning idler for a vehicle and related vehicle

The system (20) has a horizontal shaft (52) rotating a wheel (50) at a horizontal axis (B), and a housing guiding a horizontal circular plate (54) in a plane of the plate, where the housing includes upper and lower inner surfaces (70, 72). The wheel is traversed by the horizontal axis. The plate is free to move in a plane horizontal to the interior of the housing. The housing defines a rotationally cylindrical surface (77) that limits the movement of the plate in the plane of the plate, where the cylindrical surface acts as a peripheral inner surface (74) of the housing. An independent claim is also included for a front wheel drive vehicle comprising lateral sidewalls.