Description
Stock reed valves limit your YZ125’s potential across the RPM band—they’re a compromise designed for reliability, not performance. Boyesen’s dual-stage racing reed transforms throttle response and peak horsepower by matching reed stiffness to engine load, giving you crisp low-end snap and maximum flow when it matters most. Pair this with the included Rev-Plate to eliminate stock restrictions and unlock the engine’s full efficiency.
- Dual-stage design
- Lightweight top reed
- Ported bottom reed
- Improved throttle response
- Increased peak horsepower
- Rev-Plate included
- Boyesen patented technology
- YZ125 ’04 fitment
- Bolt-on installation
- MPN: 6119









