We didn't make any secret about it. We loved the 2009 Kawasaki KX450F. It won our 450MX shootout and we've ridden the wheels off it for a year. Kawasaki just released the 2010 version and the news is good. It's pretty much the same bike that we loved all along.
There are a handful of mechanical changes. The clutch received a lot of attention, the piston is lighter and the radiators are thicker. Plus there are some mild changes to the suspension and EFI mapping. But in the big picture it's the same bike. When the 450 came out last year it was staggering. The technological center piece was the EFI system. It's similar to the no-battery Keihin system that Suzuki introduced the year before, but in 2009 Kawasaki had the distinction of having done it better.
The new Kawasaki 450, like the 2009 KX450F, starts easily. In fact, we'll go so far to say it starts easier than any non-electric-start 450, carbureted or not. Another thing that the Kawasaki does better than other EFI bikes is the smooth throttle response down low. It's not hurky-jerky like the '09 Honda and it's tough to stall. That alone makes it the best EFI 450 for off-road work.
But make no mistake about it, the Kawasaki is fast. It makes a ton of power in the middle and on top. The new bike is even faster than the old one, and that verges on being too much to handle. We never asked for a bike with more snap, but we did want a longer interval between piston changes. Kawasaki technicians seem to be confident that we got that. Another very small issue was the clutch. The 2009 KX had a very mushy engagement over a long throw. It also had a short life with the stock springs. The new KX's clutch feels a little more solid. The pull is the same and at this point we don't know if the plates will last any longer.
In handling, it's exactly the same bike, but with stiffer suspension. Both ends have the optional heavy springs from lasty year. The KX is still stable and sticks to its line through the turns. It turns well, but it's never been the most agile-feeling bike in the world. It's a big motorcycle. The '09 version tipped the fabulous DB scale at 235 pounds without fuel. That's heavier than the Honda, Yamaha and even the electric start KTM. It's still lighter than the Suzuki and Husqvarna.
We were pleased with the new rubber. The 2010 Kawasaki 450 will come with Bridgestone 404 rear and 403 front tires. These are tires with larger cases, much like Bridgestone introduced on the RM-Z450 in 2008 with the 401A and 402A. The idea is to provide a cushier ride. In the front, the concept goes back as far as the old 20-inch tires of the past. We like the concept for its off-road application and full-time motocross guys like it too.
We're going to keep riding the new Kawasaki over the next few months searching for ways to make it better and exploring some off-road set ups. You can read about it in the November issue of Dirt Bike.
The KX450F isn't the lightest bike in the class, but it handles good. Mark Tilley had no trouble in the air or on the ground
If you liked the old KX450, you'll like the new one. And everyone liked the old one.
The Kawasaki's brakes are good, but not the best. A 270mm Braking rotor would put in in the same league as a KTM.
Kawasaki gave the bike a slightly different color scheme, but all the plastic is interchangable with that of the 2009 version.
The motor is incredible. It's fast, smooth and even starts easily.
One thing that didn't change for 2010 is the sound level. The KX is the loudest 450 you can buy.
New clutch plates and a tougher basket are aimed at getting more life from the stock KX clutch.