2011 Kawasakikx250f

2011 KawasakiKX250F

CW RIDING IMPRESSION

Now with EFI, SSFF and more MSRP

RYAN DUDEK

cycleworld.com/kx250f

IS IT TIME TO SAY GOODBYE TO CARBURETORS FOREVER? IF THE excellent performance of the fuel-injection system on Kawasaki’s new KX250F is any indication, the answer is yes. But even though the bike’s Keihin EFI may steal the headlines, its new Showa Separate Function Fork (that has its springing and damping in separate chambers) comes in a close second.

Our first chance to try the new green machine was near the Potomac River at Budds Creek Motocross Park in Mechanicsville, Maryland, where it took less than a single lap to begin to

feel the benefits of the KX’s Digital Fuel Injection. The batteryless system was designed to fire the engine within three kickstart-generated rotations of the crankshaft, and we found that to be the

case most of the time—but did encounter the occasional 10-kick startup a couple of times throughout the very hot day.

Although the engine has plenty of oomph, the 43mm throttle body meters that power to the rear wheel in a very precise and predictable manner, providing an excellent interpretation of what the rider has requested with the twistgrip. The engine always offers crisp response and smooth, linear acceleration from low rpm all the way to the rev-limiter. That wide spread of torque allows the rider to roost out of deep, loamy comers without the need to shift quickly on exit. And speaking of changing gears, transmission engagement is exceptionally positive without the slightest bit of notchiness or stickiness, so shifts through the gearbox always are effortless and sure-fire.

"Although the engine has plenty of oomph, the 43mm throttle body meters that power to the rear wheel in a very precise and predictable manner, providing an excellent interpretation of what the rider has requested with the twistgrip."

Kawasaki has been heeding the advice of its contracted pro riders, Chad Reed and Ryan Villopoto, both of whom prefer thin steel engine-mounting brackets on their factory racebikes rather than the traditional thick aluminum pieces. So for 2011, the showroom-stock KX250F has the steel brackets, which Kawasaki claims provide more lateral flex for lighter handling characteristics. A 1mm reduction in fork offset, from 23.5 to 22.5mm, is intended to improve front-

tire bite in comers.

Then there is the Separate Function Fork, which not only has the usual compressionand rebound-damping adjusters but now also includes adjustable spring preload. To achieve this, all the damping valves are housed in the left fork leg, and the spring resides in the right leg.

While the addition of another adjustment circuit offers the rider more frontsuspension tuning capabilities, it tends to make the actual fine-tuning process a bit more time-consuming than is with a typical MX fork. Once back on home turf, we spent a full day at Glen Helen Raceway playing with setup to find an ideal setting, of most importance trying to get the bike balanced front-to-rear. We found it best to get the shock dialed in first before making significant changes to the fork. Surprisingly, the fork is very sensitive to adjustments, whether it’s preload, rebound or compression; before finding the fork’s sweet spot, we went from harsh and twitchy to overly soft. Our optimal preload setting ultimately was right in the middle of Kawasaki’s recommended 45 to 55mm sag range. Once that was set, we ended up adding three clicks (stiffer) of compression and one more click of rebound (slower).

After a long day of testing, we were very satisfied with the performance of the Separate Function Fork, but we’re not convinced that at this stage, it offers much of an advantage over a conventional fork. It has a lot of potential, though, and with further development, it is likely to be even more effective when fitted to future models.

All of the upgrades to the 2011 KX250F resulted in a $300 bump in its suggested retail price, up from $6999 to $7299. That makes it the most expensive of the Japanese Lites-class MXers by $100. But is it worth it? Can the newand-improved KX unseat the 250-shootout-winning Honda CRF250R? We’ll have to wait and see. □