Boyesen Power Reed Dualstage Yamaha 4 Tops 4 Bottoms Includes Metal Plates Mini Mechanical stop on the tip

Mechanical stop on the tip

KX450F 13-18

SC 250 15-22

and flank protection

Yamaha YZ426F 00-02 rear

Boyesen Power Reed Dualstage Yamaha 4 Tops 4 Bottoms Includes Metal Plates Mini Mechanical stop on the tipOne reed petal is NOT enough! Boyesen's revolutionary dual stage reed design delivers more usable power than stock. Stock single stage reeds operate most effectively within a relatively narrow RPM range and are limited because of the single stage design. Boyesen's one soft reed on top of one firm flow through reed gives you a wide range of intake control, plus increased intake velocity. Your original reeds can't possibly duplicate that performance.