Drive chain RK pitch 520 for off-road motorcycles up to 500cc. The 520MXZ4 is the chain without O-Ring, a result of the new design of the components and the use for its steel production of the new formulation. In particular, the plates have a lightened profile and a thickness of 1.80 mm (internal). Despite its very low weight (more than 10% less than the best competitor) the 520MXZ4 guarantees an average breaking load of 31400N, broadly in line with that of other products with higher weight.