2012 Ktm 50 SX, Motoworld of El Cajon - It all Starts here! - A real KTM for the smallest of future MX. The 88 lbs. lightweight 50 SX sets the standard in terms of controllability and riding fun. A high-quality chassis with easily applied rotor brakes, top-quality components wherever you look and a powerful, reliable engine with easy-to-operate centrifugal clutch.