K&N’s new RK Series Filter Kit features the K&N High-Flow Filter, along with a matching free-flow backing plate and breather kit as well.

The RK Series Filter Kit also features a built-in and dyno-tuned velocity stack as part of the design.

The RK Series Filter Kit retains the stock air- cleaner cover, although K&N does provide a laser-etched
“High Flow” center beauty ring as well.

he first–or certainly second–thing many Harley buyers do right after taking delivery of their new bike is put on a K&N High-Flow air filter. Combined with one of those aftermarket or factory-performance free-flow backing plate kits it’s a wise move. A stock Twin Cam Harley is so restricted on the intake side (and the exhaust, too, when you get down to it) that this simple change reaps huge benefits.      That free-flowing K&N High-Flow filter element coupled with a less-restrictive backing plate lets that new V-twin breathe to its full potential. In less than a half-hour’s time a rider can have a bike that’s more responsive and a lot more fun to ride.
     And now–finally–K&N is offering the complete package to get that very-necessary job done. The new RK Series Filter Kit includes not only that K&N High-Flow filter element but also the matching free-flow backing plate and breather kit to go with it.      No more grabbing one part from here, one part from there and another from somewhere else. The Harley-Davidson rider’s almost-mandatory free-breathing air cleaner package can now be found at one place…K&N.
     This K&N RK Series Filter Kit is pretty special, too. The backing plate and breather package is designed to be a perfect match–and complement–to that High-Flow filter element it mounts. The K&N backing plate is constructed entirely of powder-coated billet aluminum, it’s free-breathing and completely eliminates the need for any unsightly external breathers. And, get this, there’s a built-in and dyno-tuned velocity stack that’s part of the design. If there’s a company that knows a thing or two about maximizing airflow it’s K&N, and all those decades of know-how has filtered, if you’ll excuse the term, straight into the new RK Series Filter Kit for Twin Cam Harleys.
     The RK Series Filter Kit retains the stock air-cleaner cover, too. K&N does include a laser etched “High Flow” center beauty ring should you care to use it, but you can keep the stock Harley beauty ring should you want to. Your choice. Either way, the result is vastly improved breathing and filtration, increased performance, enhanced rideability and a good chance for improved economy, too. If you can keep your right hand out of the throttle and all that newfound power now on-hand.
     The RK Series Filter Kit is available for all 1999 through 2005 Twin Cam Harleys (with the exception of the older Magnetti-Morelli FI models). Drag Specialties has it, and one call gets it.