Stud Length: 115mm. This product is suitable for the Yamaha DT 50 R (DT) 00-02 E1 (AM6) [5BK/ 5EC/ 5BL/ 3UN]. CVT Roller Sets. Racing Planet UK specialise in scooter parts and small capacity motorcycle parts, with everything from electrical parts, braking, cables and mirrors to engine, transmission, exhausts and accessories.