2021 Kawasaki KX450

The 2021 Kawasaki KX450 is an excellent and well-rounded package with subtle updates that make it even better.

With competition as fierce as it is in the full-size motocross category, the three consecutive victories that Kawasaki has garnered with the KX450 in the Dirt Rider’s comparison is nothing short of impressive. The 2021 model took another win this year because, simply put, it does everything very well.

Despite two previous victories, Kawasaki R&D kept plugging away at improvements, as the model also sees performance and ergonomic updates for 2021. This includes a new coned disc-spring hydraulic clutch, larger-diameter clutch plates with a revised friction material, piston skirt that utilizes a new dry film lubricant coating, and new Renthal Fatbar handlebar.

Priced at $9,399, this model is tied with the Yamaha YZ450F and GasGas MC 450F as the second cheapest model in the 450 four-stroke category. The Suzuki RM-Z450 is $400 cheaper at $8,999.

The KX450′s liquid-cooled, DOHC, single-cylinder 449cc engine is characterized by its quick-revving, reactive engine character and controllable power delivery. In the Dirt Rider comparison Andrew Oldar said, “It makes decent power throughout the rpm range, is very lively, and has a super-crisp throttle response. The KX450 doesn’t have the most torque, hit, or over-rev, but is a user-friendly engine that is controllable and predictable.”

On our in-house dyno, the Kawasaki KX450 recorded 52.4 hp at 9,600 rpm and 32.6 pound-feet of torque at 7,000 rpm.

The Nissin hydraulic clutch makes the pull extremely easy and remarkably light when working through the five-speed transmission.

The aluminum perimeter frame and Showa suspension work well together to absorb impacts and are firm enough to respond well to rider inputs. Overall, Dirt Rider’s Andrew Oldar wrote the KX450 “is very maneuverable, corners easily, and is able to change lines at a moment’s notice while still being stable and predictable at speed,” all of which make it the best-handling chassis in the class.

The Kawasaki is fitted with a Nissin two-piston caliper and 270mm disc out front and a Nissin one-piston caliper and 250mm disc out back. The latter pairing drew some complaints because it was a bit touchy and easy to lock up.

Real-world miles per gallon is not currently recorded. The KX450, like the Yamaha YZ450F, has a 1.6-gallon tank, which is smaller than the 1.7 or 1.8 gallons of fuel its competition can hold.

The Kawasaki KX450′s Ergo-Fit allows for handlebar, footpeg, and seat adjustments, but that’s not the only reason the bike’s ergonomics are comfortable. The bike’s thin structure and flat seat allow for ample rider movement, and the new Renthal Fatbar 839-bend handlebar improves the rider triangle compared to the previous setup.

The KX450 is fitted with Kawasaki’s launch control as well as three optional EFI couplers, the latter of which seem outdated since the bike’s competitors have a handlebar-mounted engine map select button.

Warranty and Maintenance Coverage

Warranty is not available for this model.

The Kawasaki KX450 offers an enjoyable ride, improved ergonomics, great suspension, and an easy clutch pull, all for an agreeably priced, well-rounded package.