Not too long ago, Kawasaki revealed on paper a trimmer, slimmer and what they said was a faster KX250F for 2013. And they recently proved it on the track by giving us and other members of the media a chance to ride the highly revamped motocrosser at one of the premier motocross facilities in the United States - Spring Creek MX in Millville, Minnesota. Over a two-day period, we logged more than eight hours on our designated test bike, which also included some serious off-road time on the track's surrounding trails.
Kawasaki made numerous (30 in all, we're told) changes to the 2013 KX250F. Some of those changes include narrowing the distance between the frame's main spars by four millimeters, designing a flatter seat, gusseting the frame in strategic areas, installing softer and longer grips, and redesigning the radiator shrouds and airbox shape - all in the name of making the bike more comfortable and easier to throw around.
The motor also received some attention. Compression ratio has been bumped up a bit, intake ports have been widened and a new exhaust system has been installed. The header pipe is 30mm shorter and now incorporates a resonator chamber to help enhance low-end power and reduce noise. The muffler is also shorter and a little taller, and the outlet hole his 7mm wider.
The airbox is reshaped and the intake tract to the combustion chamber is straighter and more direct. Photography By: Adam Campbell
Kawasaki made a huge effort to give the KX a slimmer profile, giving it a narrower frame, new side panels, radiator shrouds and airbox. The seat is even flatter.
Like its bigger KX450F brother, the 250's Keihin Digital Fuel-Injection system now comes with three color-coded pre-programmed ignition map couplers - standard, hard (smoother delivery for hard terrain) and soft (harder delivery for soft terrain). The couplers, which are clipped to the frame's steering head and are easily accessible, can be swapped out in literally seconds, and they can be custom tuned with Kawasaki's KX FI Calibration Kit if you are so inclined.
The KX retains its dual injector system, which was introduced last year and did wonders in broadening out the power.
The suspension wasn't ignored, either. It still retains its Showa SFF (Separate Function Forks) but the tubes have been bumped up from 47mm to 48mm, and, as a result, the internal damping components are larger, which Kawasaki says is a benefit because it allows the same damping forces to be achieved at a lower internal pressure, thus allowing for firmer damping response and improved overall fork action.
In addition, the fork's compression rod has been inverted, which puts the cylinder at the top of the fork and the rode at the bottom. Kawasaki says this change ultimately improves bottoming resistance and increases overall rigidity of the fork.
The shock has revised settings to coincide with the chassis changes and new fork, and the swingarm features a longer cast front section and new tapered hydroformed spars for improved traction and stability when hard on the gas exiting the turns. And the chain now rides on a more durable chain pad, which was definitely a weak area with previous models.
After the two-day introduction, our KX had over eight hours on the meter. Photography By: Kit Palmer
Other significant changes include a new pushrod-type front brake master cylinder, new front-brake pad material, a smaller front number plate and a redesigned front fender.
It also has new Dunlop Geomax MX51 knobbies.
Our first impression of the 2013 KX250F was a good one. In fact, it didn't take us long at all to actually fall in love with the KX's motor on the spacious and horsepower-demanding Spring Creek track. It packs a serious punch yet is remarkably easy to manage thanks to its rather wide powerband and robust and bottom end. It pulls hard right from the get-go and never lets up, and it's quite torquey for a 250F motocrosser. It revs out nicely on top and doesn't punish you too much when you hit the rev-limiter, until then it just keeps making power. Very impressive.
The KX's motor is impressive. Photography By: Kit Palmer
And the five-speed transmission works well with the motor.
We never really felt the need to change mapping, but we tried out all three pre-programmed couplers anyway. We found the differences from one coupler to the next are noticeable but subtle. Our favorites at this track were the standard and hard-terrain maps, both offering very manageable yet still aggressive power deliveries. Compared to the standard and hard-terrain maps, the most aggressive soft-terrain coupler blew through the meat of the powerband a little too quickly for our tastes, requiring a bit more shifting. But in ultra-loamy conditions, like we experienced when parts of the Spring Creek track were tilled for our second day of riding, the soft-terrain map was welcomed.
The KX meets the AMA's new 94dB sound level requirements but we doubt by much. The KX seems a little on the loud side while producing a distinctively throaty, and even raspy (at high rpm), note.
We were also impressed with the KX's ergos and trimmer profile. The overall slimmer and smoother profile, not to mention the flatter seat, makes moving around on the bike a breeze. And there is nothing to catch your boot or gear on.
The KX's suspension is hard to fault, at least so far. We're anxious to get the bike on some more familiar turf for further evaluation, but at Spring Creek, at least, we were quite happy with the KX's suspension, front and year. We made only a few clicker changes over the two-day period. The bike feels solid and stable, and turns well but maybe not a quick or as responsive as we would have liked. We had some issues with the bike standing up in the ruts by mid-corner, but after some experimenting fork-tube placement in the triple clamps, making some preload and damping adjustments, and fiddling rear-end sag, we got the bike to stay more planted all the way through the corners.
We even did some off-roading on the KX. Spring Creek also hosts a round of the OMA Series. After riding some of the trials, the race has been added to our must-do list. And the KX will do just fine. Photography By: Adam Campbell
As mentioned, we also got the chance to hit some of the awesome single-track trails that surround the Spring Creek motocross facility. As evident by the deep ruts, many of the trails we rode are obviously used when the OMA off-road Nationals comes to town. As with most highly strung 250F motocross bikes out there, we figured the KX would be a handful on the tight and technical trails but we figured wrong. The KX actually performed surprisingly well. It has enough torque and useable bottom-end to pull you out of the tight spots without having to abuse the clutch. And we were blown away that the motor never once stalled or flamed out, and we certainly gave it plenty of opportunities to do so - like while climbing over some pretty mean logs and roots. We also found the "hard" coupler to be very desirable in the tight stuff.
The suspension worked well on the trails, too, but was, with no surprise, a little on the stiff side overall.
Still, we had a blast tearing up the woods on the KX, trying to do our best Paul Whibley (three-time OMA Champion) imitation. We doubt it will take much effort turning the KX into a serious and very rideable off-road racer.
There were a few other things that stood out in our minds after riding the bike for the first time, like the updated, 250mm front disc brake, which has a much better feel and is much stronger than before.
We welcomed the new, softer grips, but they are, unfortunately, only marginally better than the previous grips. Luckily, they are no longer "cemented" into place, making replacement much easier.
The new Dunlop MX51A front tire seemed to offer sufficient grip, too, at least on this track.
Overall, we left Spring Creek quite pleased with the new KX250F and its powerful motor and improved ergos. We look forward now to riding the KX on other tracks and giving it a thorough testing. We'll have more on the 2013 Kawasaki KX250F in a future issue of Cycle News.
The new Kawasaki KX250F should be available soon with a $7599 MSRP.