Motorcycle and Car Performance Accessories. K&N Performance Air Filter Yamaha YZF-R6 1999 – 2005. This K&N Air Filter is designed to fit model years Yamaha YZF-R6 1999 2000 2001 2002 2003 2004 2005. For over 40 years K&N has been designing and manufacturing performance air filters for motorcycles. They provide a high, virtually unrestricted air flow while maintaining filtration levels critical to ensure long engine life. Designed as a direct replacement for the stock motorcycle air filter element, K&N s washable and reusable pleated media air filter provides a large filtration area for a better throttle response, more horsepower and long service intervals. Fuel management modifications are not normally required for increased performance. Designed to provide increased horsepower and torque. Pleated media provides a large filtration area offering long service intervals. Multiple layers of woven cotton gauze media offers excellent filtration. Application specific base seal and sealing bead. Made in the USA for over 40 years. Washable & reusable, pre-oiled and ready to ride!