has left its KFX450R well enough alone but it continues to hold the favor of many sport ATV riders for one important reason – reverse. There are certainly other features and characteristics about the KFX that make it different from other sport quads, but the 450 class is increasingly devoid of four-wheelers that back up. It’s definitely one of our favorite attributes, but there’s much more to this green meanie.
“The big bonus on this for me is that it has reverse,” says Gibson. “Any quad in the woods definitely needs the ability to back up.”
Kawasaki uses a 449cc engine with DOHC but only four titanium valves compared to Yamaha’s five. Bore and stroke are similar at 96mm x 62.1mm. The Kawi employs a 42mm Keihin throttle body for its digital fuel injection (DFI) system. One tester noted that the YFZ fuels a little cleaner, but the KFX runs great and comes to life easily with its electric start. Neither quad offers a backup kick start, and the KFX eats batteries with a vengeance.
The five-speed transmission places reverse below first gear, so the rider actuates with a reverse-lock release lever and then taps down into reverse. As for the rest of the transmission, the gears are relatively close together which makes upshifting a seamless affair, even when poorly timed. But, in order to hang with the YFZ it almost needs a sixth gear, or rather wider spacing between the existing five cogs. First is very low and most tight trail riding can be done in second. Spacing them out, or simply adjusting the final drive ratio would give the KFX a bit longer legs. As it is, the Kawi shifts well and is well suited to the engine character. The 450R puts power down to the ground with authority from off-idle all the way through a robust midrange. Once the revs get into the upper limits, the Kawasaki stops accelerating and falls off quickly. Short-shifting works best and the green ATV as an easy clutch pull. It makes for easy launches and works well for less experienced riders.
The torquey engine uses strong bottom-end and midrange punch to keep the Kawasaki feeling lively on the trails.
“All around this bike is money,” adds Hutch. “It’s got reverse, it’s got the best bottom end, the best midrange, it’s a narrow width and it has kind of a stubby wheelbase. When you’re out in the woods, this thing is super-agile.”
That agility also won over our other testers. In the dunes and on fast sections it equates to a tendency to oversteer, but switchbacks and situations that require instant corrections favor the green quad. Where the narrower track is more difficult to span ruts, it’s better at holding a high line around them, and can squeeze past obstacles. Narrower front tires help turn the Kawi quicker but the Yamaha’s front treads have a traction advantage in the dunes as it slides more uniformly front-to-rear. Our riders commented on a shorter wheelbase, but it’s only 0.6 inches shorter at 49.4 inches. The punchy, tractable engine and lighter weight (392 lbs. claimed wet) helps give the sensation of closer-set wheels.
Where the Yamaha gets praised for its roomy layout, the Kawasaki is a much tighter seating arrangement. Most of our testers wished for more space and noted that the fenders create stopping points for moving around the cockpit. However, compact ergonomics are only a bummer if you’re a tall rider. The Renthal Fatbar handlebars are closer to the rider’s lap and create more of a hunched position when standing. Also, the footpegs aren’t quite as stout as the Yamaha’s
“I’m a short guy. When I get in here, everything is right there,” says Ken in reference to the controls.
Kawasaki's aluminum chassis is very stiff which helps with high-
speed cornering, but also transfers jolts to the rider.
“It’s a little less-aggressive riding position,” adds the slightly taller Gibson. “The riding compartment is a little cramped. Nothing that is uncomfortable.”
The aluminum chassis is designed to be very stiff and makes use of a similar single-tube lower design as the Yamaha which allows for longer lower A-arms. The rear piggyback Kayaba shock is adjustable with high/low compression and rebound. Our testers were happy with the performance of the rear end with its aluminum swingarm and 10 inches of travel, but weren’t quite as pleased with the front end, its 8.5 inches of travel and dual-rate springs.
“The faster you go, the more the suspension rattles you. It’s constantly shaking,” says Hutchison regarding the front end.
The shorter overall suspension travel isn’t the issue so much as the rigidity of the Kayaba shocks. Both front components are piggyback units with high/low compression, rebound and preload adjustment. In order to absorb the larger impacts blowing through the stroke and bottoming, we have to run the shocks fairly stiff, and the compliance on small trail garbage is not comfortable. Bumps are transferred to the rider and it takes a lot of effort to control the handlebars.
Even though the Kawasaki isn’t a special edition version it still has some nice features, plus a lower MSRP ($8099), like the Renthal bars
, LED brake lights, heel cups, skidplates and lapped front and rear fenders. The fender design allows for individual replacement when damaged or for a smaller profile during sand riding. Kawasaki also equips the
Kawasaki uses clean features like compact headlights and
reinforced rim plates to add value to a well-roundad package.
KFX450R with an easy-to-use parking brake.
“Imitation is the sincerest form of flattery,” muses Hutchison. “Finally they’ve got the Yamaha-style parking brake which just makes this thing even better.”
Our riders also liked the Kawasaki’s headlights better, not necessarily because they shine brighter, but because they proved more durable and are tucked away more effectively to shield from abuse. Our Yamaha had a light housing broken simply from vibration, which was a bummer. They’re also physically larger than the KFX’s which exposes them to roost and debris. The Kawi has workable lights that are relatively well protected.
As it turns out, the Kawi’s strengths are its usable engine with reverse and agile handling, while cramped ergos and rough suspension hold it back. The Yamaha is opposite with amazing rider comfort and stellar suspension, but a high-rpm engine that only goes forward. Either of these sport ATVs can be the right choice depending on where you ride.
With a big push in recent years for motocross-specific quads, there has been a slight loss for hard-core 450 riders who need or want to take their machines away from the track. Our Southern Oregon area is a perfect example. The two public motocross tracks within an hour drive both shut down during the winter due to mud and snow, and you can bet damn well that our ATV population isn’t just packing it in with a shrug of the shoulders. With a slight bias toward our tight trails, we were very pleased to find that the MX-model Yamaha is still plenty capable of heading away from groomed jumps. The most aggressive of our testers preferred the Yamaha overall, but the other two riders would happily adopt either into their personal garages. All of the riders agreed that the YFZ is still a valuable ride off the track, and the Kawi impresses with its easy-going, hard-working nature.