Achtertandwiel, atw, kettingwiel, akw 48 tands Derbi GPR, Aprilia RS50 vanaf bouwjaar 2006>, RX50, Sachs Madass 108mm binnenmaat.

52 Tands is standaard achter: Motor Hispania Road50 RX 05-09, Peugeot Road50 XR6 02-06.
53 Tands is standaard achter: Aprilia Road50 RS 06-09, RS 10-1350, RS4 12-1350, RS4 Replica, 12-13Derbi Road50 GPR Nude 04-0550 GPR Nude 06-0850 GPR Racing 04-0550 GPR Racing 06-0850 Senda SM DRD Evo 09-1050 Senda SM DRD Racing 1150 Senda SM DRD Racing 1150 Senda SM DRD Racing Limited 07