First Ride: 2010 Kawasaki KX250F

They say that change is good, but sometimes, no - or in this case little - change is good, too. A prime example of this is the 2010 Kawasaki KX250F, which we got to ride for the first time at Castillo Ranch in California, yesterday, where Kawasaki let loose with its new green machine to the media.

Actually, the KX250F does feature a fair amount of changes for 2010 but nothing too dramatic. Most of the updates involve increasing durability, such as designing a stronger and lighter piston, fine-tuning the bottom end, and making small refinements to the transmission. The radiators are also larger, stronger and redesigned to be more efficient.

The KX did get some performance-minded changes, however, such as reshaping the exhaust header pipe, revising the muffler, and updating the camshaft.

As far as the motor is concerned, the bottom line is: If you liked last year's KX, you'll like this one, too. It performs much like the '09 KX did, which is fine with us, since we loved last year's motor. Like last year, the 2010 KX makes good, useable power over a rather wide rpm range, yet is still a high revver. According to a Kawasaki-supplied graph, horsepower curve is nearly identical to last year's but with a tick more power right off the bottom and in the higher rpm range. Peak horsepower appears to be the same, but it gets there a few Rs quicker and seems to maintain peak power a bit longer, too.

On the track, the bike does appear to be a bit more freer-revving and stronger on top, but nothing too drastic. That's okay, though, because the Kawasaki was already one of the strongest 250Fs out there.

At first, we were surprised - and maybe a little disappointed, too - that the new Kawasaki was not fuel-injected, but, as it turns out, we're okay that, since the Kawi carburates so well anyway. Our test bike ran just fine right out of the crate. If anything, the KX might be a little rich on the mainjet, but we'll put more time on the bike before we start thinking about swapping jets. For now, however, we're quite happy with the Kawasaki's jetting and carburetion in general. We can hold out another year.

Starting couldn't get any easier. With the gentlest of kicks, our bike started up first time, every time. Hot or cold.

In the motor department, we got to let the KX really dig into the loose central coast terrain, where it was pulling our light-weight and heavy-weight riders up the rolling hills of Castillo. The KX pulls hard, and revs to the moon, as we would find out from hitting step-ups in second gear pinned lap after lap. 

Suspension has been updated, too. Both the Showa twin-chamber fork and Showa shock took on some damping revisions. The fork also got Kashima coating on the inside of the outer tubes to go along with the titanium coating on the lower tubes, all to reduce stiction and improve fork action. The steering stem shaft has also been reduced from 24mm to 23mm to reduce rigidity.

As mentioned, the shock gets new damping settings and rides on new linkages with revamped ratios. The swingarm has also been redesigned to reduce rigidity and improve handling.

On the smooth Castillo track there was plenty of deep loam where we could stretch out the KX's powerplant, but it wasn't a good challenge for the Kawie's chassis/suspension, so we'll put our little green machine through more paces before commenting on exactly how the '10 stacks up. For now, we can say it feels quite familiar so far... much like the '09 KX250F which is a good thing since we named it the best quarter-liter motocrosser last year.