From the July/August issue of ATV Rider Magazine.
The high-performance market was really heating up in 2008 when Kawasaki hit the market with the KFX450R. EFI, aluminum chassis components and exotic designs abounded. It seemed as soon as we finished testing the latest 450, there was another one hitting the market. In 2008, the KFX was impressive, but through the years it has become sort of a middle sibling, perhaps not getting all the attention it truly deserves. So we ordered a unit from Kawasaki to rediscover the machine and see what it has to offer. Kawasaki is one of a small handful of manufacturers offering current model 450s this year. Some manufacturers are still trying to sell off 450s they overproduced a couple years back. Purchasing a current model means it will be worth more in a few years when you decide to sell it or trade it in.
Over the past few years, the KFX has remained mainly unchanged with the exception of a wiring harness and other minor updates. Yet compared to the machines that have come since, the KFX is still pretty state of the art. The engine is based on the 2008 KX450 dirt bike engine that has been optimized for use in an ATV. The four-valve, single-overhead-cam, four-stroke engine features lightweight titanium valves with aluminum valve spring retainers. The valves along with a lightweight forged piston help reduce reciprocating weight. For durability, the piston has a three-ring design with a 21mm-diameter piston pin, and a 32-bit fuel-injection system delivers the vapors via a 42mm throttle body. The task of getting the power of the engine to the driveline is done through a five-speed manual transmission that also features reverse gear. This is a big plus for trail riders and some racers, as is a quick-change cover that makes clutch access easy for a quick clutch swap when necessary.
A stout-looking aluminum frame with removable aluminum subframe keeps the overall weight down without sacrificing strength. The one-piece main frame was built to be rigid and responsive with a single boxed lower front frame rail, which mounts the front gullwing-style steel A-arms as closely together as possible to help reduce bumpsteer. To soak up rough chop and rough landings piggyback-reservoir-equipped KYB shocks are installed with the front suspension. The KYB shocks feature preload, compression, rebound damping and give the machine 8.5 inches of travel, which is a bit shorter compared to other machines in its class. At the back end of the KFX, Kawasaki attached a lightweight rigid cast-aluminum swingarm that works with a linkage and piggyback-reservoir-equipped KYB shock, which like the front features preload, high- and low-speed compression and rebound-damping adjustments providing 10 inches of travel.
Bringing the sporty green machine to a stop is accomplished by the dual hydraulic discs up front and a single hydraulic disc in the rear. The front brakes feature 163mm rotors with dual-piston calipers, which are activated by the reach-adjustable handlebar-mounted brake lever, and the rear brake features a 200mm rotor with a single-piston caliper. Transferring the propulsion or stopping power to the ground, general-purpose Dunlop tires are mounted on a set of high-quality aluminum wheels. The nine-inch rears feature reinforcing rings that greatly increase their durability. Other nice features include the 11⁄8-inch Renthal handlebar, reversible bar mounts (which allow you to move the bar forward or rearward) and a seat cover that is smooth on top and rough on the sides, allowing you to move around easily in the saddle and grip the machine while standing. The dual 30-watt headlights and LED taillight are easily removed for competition purposes.