SuperSprox 520 Front Sprocket Yamaha Fz-09 / Fj-09 / Xsr900 / Tracer 900 Features Real Factory Team specification parts from the company supplying real factory teams Ultra-hard surface layer (0.5mm) reduces friction to prevent power loss caused by chain drag Made from Scm-435 Carbon Free steel and impregnated to guarantee zero breaking risk and extended sprocket life Fully lightened with radial holes for off-road and street applications