Back to Moto Exhaust

FMF Factory 4.1 — RCT Stainless Full System — Yamaha WR450F (2024-2026), Yamaha YZ450F — (see

Part # 044477
Item #357805
Fits 3 motorcycles
  • Yamaha
    • WR450F · 2024–2026
    • YZ450F · 2023–2025
    • YZ450FX · 2024–2026
Regular price $1,074.99 Sale price$967.49 Save $107.50
/
Shipping calculated at checkout.
  • Low stock - 4 items left
  • Backordered, shipping soon

  • Free U.S. shipping on orders $150+ ($15 flat under)
  • Ships from one of three U.S. warehouses
  • Secure checkout
WARNING: Cancer and Reproductive Harm — www.P65Warnings.ca.gov
FMF Factory 4.1 RCT Stainless Full System — Yamaha WR450F (2024-2026), Yamaha YZ450F (2023-2025) + 1 more, 4-Stroke
Product Details

The Factory 4.1 RCT in stainless steel construction. Same Resonance Chamber Technology and power gains as the titanium system, with a stainless mid-pipe and muffler body for budget-friendly toughness. Shorter length, lighter than stock, and quieter than OEM with FMF's Rapid Tuning System.

  • FMF Resonance Chamber Technology (RCT)
  • 304 stainless steel construction — rugged and corrosion-resistant
  • Shorter overall length for mass centralization
  • Rapid Tuning System (RTS) — sound insert and spark arrestor swaps
  • Quieter than stock with weight savings

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

  • Yamaha WR450F (2024-2026)
  • Yamaha YZ450F (2023-2025)
  • Yamaha YZ450FX (2024-2026)

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.