RFX Race Sprocket 15 Teeth — Manufacturer reference: FXFS 37-15 55ST. Designed for motocross use, this RFX front sprocket is intended for transmissions equipped with a 420 pitch chain. Its silver finish and standard version make it a sleek and reliable part for replacing or adjusting your final drive ratio.
CNC machined from alloy steel and then case-hardened to achieve a high hardness (≈60 Rockwell), this sprocket offers tight tolerances for precise engagement with the chain and the rear sprocket. The machining ensures a smooth surface to limit premature wear, while some RFX models feature lightening holes to reduce mass without compromising strength.
- Brand: RFX
- Number of Teeth: 15
- Material: Case-hardened steel
- Chain Pitch: 420
- Color: Silver
- Version: Standard
Compatible with motocross models such as YAMAHA YZ 65 (2024–2026) and other machines accepting a 15-tooth sprocket in 420. Easily replaces the original sprocket to adjust your gearing, optimize traction, or restore expected engine behavior on the track.