K&N 04-09 Yamaha XT660R/XT660X Super Replacement Air Filter - YA-6604

K&N off-road replacement air filters are ideal for extended use in dirty and dusty off-road riding and provide clean carburetion even at high altitude. Generally, no jet changes are required with just a K&N filter element. K&N replacement air filters are washable and reusable and provide high air-flow with excellent filtration.
Installation Instructions