Used by team Yamaha Pro racers; This stabilizer is extremely adjustable and rugged. This Precision Stabilizer was designed for the Yamaha YFZ450R 2009 and on and comes with all hardware needed for an easy installation and mounts up to your YFZ in approximately 20 minutes; no drilling, welding, or grinding needed. The Pro stabilizer has a built in reservoir to compensate for thermal expansion. The stock steering stem diameter for the YFZ is 1.25". All known after market stems will fit.