RFX Pro Series Elite Aluminum Sprocket - 420 (Manufacturer part number: FXRS 56-51 99BU): a sprocket designed for off-road and motocross competition. CNC machined from 7075 aluminum, it features 51 teeth with a 420 pitch, an optimized CAD profile to reduce weight while maintaining precise geometry. The blue anodized finish and laser-etched RFX logo give it a race look on your rear end.
- Material: CNC machined 7075 aluminum.
- Number of teeth: 51 — 420 pitch, compatible with lightweight motocross machines.
- Mud evacuation grooves to limit accumulation and promote even chain wear.
- CAD profile for a balance of mass/stiffness and tight tolerances for precise coupling with the chain.
- Color: anodized blue — RFX color code per model and also available in silver.
- Stiff design engineered to limit torsion under heavy use.
Designed for motocross riders who want a lightweight, precise, and mud-resistant sprocket. Suitable for KTM 65 SX (2022, 2023) and KTM 60 SX (2000) models — check the pitch and bolt pattern before installation. Ideal for replacing your stock sprocket and achieving a race finish on your bike.
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