520 Motorcycle Front Rear Sprocket Kit Fit For Betamotor 250RR 350R 400RR 450RR 498RR 520RR 525RR Fit For Betamotor 250RR 350R 400RR 450RR 498RR 520RR 525RR enduro motorcycles; compatible with output shaft splines, rear hub bolt layout standard 520 drive chain direct bolt-on assembly without grinding or frame ; enables quick full drivetrain overhaul for trail race self-cleaning curved tooth grooves discharge mud grit dirt efficiently; lower chain friction to deliver linear torque for climbing fast offroad acceleration induction treated carbon with thick reinforced tooth roots; outstanding abrasion resistance under muddy rough terrain continuous high-rev riding manufactured to OEM dimensional standards with uniform tooth pitch symmetrical mounting holes; tight seamless meshing with chain to cut vibration extend full drivetrain life