Description
Stock reed valves limit your engine’s breathing potential, costing you power from idle all the way to peak RPM. Boyesen’s dual-stage reed design has been laboratory-validated to outflow standard reeds across the entire operating pressure range, delivering measurable gains in throttle response, acceleration, and top-end performance. If you’re serious about extracting every bit of power from your Kawasaki or Yamaha 620, upgrading to racing-spec reeds is one of the most cost-effective modifications you can make.
- Dual-stage reed design
- Laboratory flow-tested
- Increased flow velocity
- Optimized startup performance
- Enhanced mid-range acceleration
- Improved top-end power
- Kawasaki/Yamaha 620 fitment
- Bolt-on installation
- OEM replacement reed set









