K&N is the official air and oil filter sponsor of the 2014 Cycletrader.com Rock River Powersports Yamaha racing team seen here with team rider Ben Lamay
Yamaha began the four-stroke motocross revolution in 1998 and was ahead of its time. Many diehard fans of the tried and true two-stroke MX bikes laughed at the idea of a four-stroke motocross machine until Doug Henry successfully raced one in the 1998 Supercross series and they could laugh no more. The 1998 Yamaha YZ400F changed the face of motocross but was far from perfect. For years Yamaha, and its competitors, would work to iron out the wrinkles of four-stroke motocross technology until the two-stroke was nearly made extinct. In 2010 Yamaha introduced another revolutionary YZ-F, taking motocross motorcycle design to another level of forward thinking. The 2010 YZ450F wasn’t well received but for 2014 Yamaha worked hard to address the flaws inherent in the 2010-2013 models. Also, fresh for 2014 was the all-new YZ250F that is just as radical as the 2010 YZ450F motorcycle. This time though, Yamaha took hard learned lessons from the previous four model years of the YZ450F to make the 2014 YZ250F and excellent race bike right out of the box.
Replacement K&N air filter, number YA-4514XD, is designed to fit inside the stock air filter box of 2014-2016 Yamaha YZ-F models and includes a support frame for even sealing
Despite the forward thinking mass centralization technology built into the engine, suspension, and chassis of 2014, 2015 and 2016 YZ450F and YZ250F models, Yamaha equips these machines with a uninspiring air filter made from foam. 2014-2016 YZ450F and YZ250F owners can now equip their motocross bikes with the high-flow air filter technology incorporated into K&N replacement air filter, part number YA-4514XD. The new replacement K&N air filter YA-4514XD, is designed to fit into the stock air filter box without any need for modifications. K&N replacement air filters are made with specially woven cotton gauze. Because cotton, by nature, is more breathable than foam, K&N replacement air filters can flow more air than a typical foam air filter. More air can result in increased acceleration, improved throttle response, and more power.
The 2014-2016 Yamaha YZ450F and YZ250F models have a unique air filter box located at the front of the seat as seen here on David Pulley’s 2014 Supercross bike
It would be false to assume that an increase in airflow with a K&N air filter comes at the expense of filtration efficiency and engine protection. K&N engineers placed filtration efficiency and dirt retention at the top of the priority list when developing air filter number YA-4514XD for the 2014, 2015 and 2016 YZ450F and YZ250F models. K&N knows that a YZ450F or YZ250F will be raced in some of the most extreme conditions on the planet. This is why K&N paid extra special attention to the design of replacement K&N air filter YA-4514XD.
Perhaps the most important feature used in YA-4514XD is the four layers of our special tight weave cotton gauze sandwiched between wire mesh to form extra deep 1-1/4” pleats. Four layers of 1-1/4” deep pleated cotton filter media allows YA-4514XD to outflow the stock air filter, hold more dirt for long service intervals, and offer 97.44% overall filtration efficiency. K&N Yamaha YZ450F & YZ250F air filter YA-4514XD for 2014-2016 models utilizes an application specific support frame to ensure even pressure around the entire sealing surface.
K&N performs filtration efficiency testing following the ISO 5011 protocol with ISO coarse test dust to guarantee that our air filters will provide high airflow without sacrificing engine protection. Calling this test dust coarse is almost preposterous, as 22% of the dust is rated at 10 microns or less. To provide perspective, a human blood cell is typically between 6 and 8 microns across. K&N has made these detailed airflow and dust retention test results available for viewing.
Part number YA-4514XD can be washed and made like new using one of the K&N Recharger air filter service kits. Recharger, 99-5000, includes 12 fluid ounces of air filter cleaner and a 6.5 ounce aerosol bottle of air filter oil for quick and easy application. Recharger, 99-5050, differs in that it includes an 8 ounce squeeze bottle of K&N filter oil for a more precise application. K&N air filter oil is key to trapping dirt and providing high levels of engine protection, yet it doesn’t have that gross sticky texture like foam air filter oil.
It isn’t just K&N that thinks highly of the new YA-4514XD replacement air filter for 2014-2016 Yamaha YZ450F and YZ250F motorcycles. David Pulley, a privateer who raced the 2014 Supercross season in the 450 class, had this to say of his YA-4514XD air filter “Filter is awesome! Better throttle response and more hit on the bottom. It's working great! Sounds really good too.” Additionally, the Cycletrader.com Rock River Powersports Yamaha professional and amateur race teams used YA-4514XD with excellent results.
Air filter YA-4514XD for 2014 and 2015 YZ450F and YZ250F models is backed by a one year limited warranty. Replacement air filter YA-4514XD is designed to provide increased performance, reusability, and long air filter service intervals without any need for modifications or tuning for the following Yamaha YZ-F and WR-F motocross racing motorcycles:
2016 YAMAHA YZ450F 450
2016 YAMAHA YZ250F 250
2016 YAMAHA WR250F 250
2015 YAMAHA YZ450F 450
2015 YAMAHA YZ250FX 250
2015 YAMAHA YZ250F 250
2015 YAMAHA WR250F 250
2014 YAMAHA YZ450F 450
2014 YAMAHA YZ250F 250
A full list of K&N's Yamaha YZ450F air filters and Yamaha YZ250F air filters are available on KNFilters.com.