RFX Pro Series Trials Rear Sprocket Current Beta Gas Gas Montesa Sherco Underwear Riding Strategically positioned laser perforations for 3012856RK Strategically positioned laser perforations for additional airflow and optimum ventilation D brand drive chains and aluminium rims are all manufactured in Kaga Beta Year Pitch Part Number Rev 3 125 200 00 08 520 FXRS 91 43 Rev 3 250 270 00 08 520 FXRS 91 41 Rev 3 4T 250 00 08 520 FXRS 91 42 Evo 2T 125 09 19 520 FXRS 91 43 Evo 2T 250 290 09 19 520 FXRS 91 41 Evo 4T 250 300 09 19 520 FXRS 91 42 Gas Gas Year Pitch Part Number TXT Trials 02 19 520 FXRS 91 42 Montesa Year Pitch Part Number 4RT 05 19 520 FXRS 91 42 Sherco Year Pitch Part Number 250 300 02 19 520 FXRS 91 42 Scorpa Year Pitch Part Number SY250 11 13 520 FXRS 91 42 Tighter Tolerances improve performance