FMF Factory 4.1 — RCT Titanium Anodized Full System — Yamaha WR250F (2020-2021), 4 — (see

The Factory 4.1 RCT incorporates the latest in FMF Resonance Chamber Technology (RCT) — both internally and externally. A patent-pending shape enhances and refines the exhaust pressure wave for optimal power output while lowering the sound level. Constructed from aerospace-grade titanium with a carbon end cap, the system is shorter, lighter, and quieter than stock.

• FMF Resonance Chamber Technology (RCT) for power + quieter operation
• Aerospace-grade titanium construction with carbon end cap
• Shorter overall length — less crash-damage exposure, mass centralized
• Rapid Tuning System (RTS) for easy insert and spark-arrestor swaps
• Quieter than stock with huge weight savings
• Manufactured 100% in Southern California

Fitment: 4-stroke bike specific — fits the following models:

• Yamaha WR250F (2020-2021)

This is a 4-stroke exhaust. It is engineered for the 4-stroke engine architecture above and physically will not fit a 2-stroke bike. Verify your engine type before purchase.