Boyesen's patented dual-stage reed design incorporates a specially shaped top reed and a ported bottom reed. The top reed is lightweight and resilient for crisp throttle response at partial throttle or low RPMs. The stiffer, bottom reed is ported to provide maximum flow and horsepower at higher RPMs.
Fits: Honda CR250R 1979-1980 1986-1989 Kawasaki KDX200 2007-2008 Suzuki RM250 1987-1988