K&N users would probably be surprised by the amount of air filtration testing and scientific research that goes on in K&N facilities as well as in independent laboratories. As the leader and originator of the high flow performance air filter we are always looking for new ways to provide excellent protection and maximum power for your car, truck, motorcycle, and just about anything else with an engine. In 2005 more than 1600 vehicles were tested by K&N's R&D group on dynamometers in the US, United Kingdom, and the Netherlands. In addition to these power and torque tests, we also performed more than 110 filtration tests and more than 1,200 air flow tests with our in-house state-of-the-art test equipment. Select one of the links below to read or listen to more information on air filters and the science behind their design and function.

K&N Replacement Air Filters are designed to fit right into the standard OEM airbox. No modifications are required by the owner, no jet changes or adjustment of the carburetors is anticipated or suggested. Customer modification of the standard airbox - removing the cover, drilling holes into the side or top will have a drastic effect on smooth carburation. Modifications will cause the standard system to run lean and reduce horsepower. Keep your motorcycle standard and the new K&N Replacement Element will be good for the life of the engine.