Ryan Nitzen | December 2, 2023
The Kawasaki KX450 is one of the most anticipated 450cc motocrossers of the 2024 model year. Essentially, the green machine is new from the ground up—engine, frame, bodywork, electronics, the works. According to Kawasaki, its goal was to build on the strengths of the outgoing KX450, which was a well-liked motorcycle during its previous 2019-2023 generation, and make it more of an “all-arounder” race bike. Did they nail it? Let’s find out.
Photography Kit Palmer
What’s Changed? | 2024 Kawasaki KX450 Review
For one, the airbox. It has been completely reformed. Previously, the air intake design routed air around the rear shock. Now, it routes the air more up and over the shock for a straighter, downward shot into the cylinder. Paired with a new center port exhaust system that aligns straighter with the intake ports, this new intake design, Kawasaki claims, is better streamlined and efficient, resulting in a smoother and more consistent engine character with a “boost of performance.”
The air filter element is radically different, too. It’s completely flat. It slides into position and is held in place via two clip-in mounts. No tools are needed to access or remove the filter element, accomplished through the left side panel.
The 2024 Kawasaki KX450 is essentially new from the ground up.
The KX’s aluminum perimeter frame has several revisions to accommodate the center exhaust port and new intake tract system. A new, shorter Showa rear shock has been slightly repositioned in the frame. Despite being physically shorter, the shock did not lose overall stroke length. A cool new feature is the adjustable upper engine mounts that Kawasaki offers as an option. Kawasaki says the adjustable mounts change the feel of the bike’s overall handling characteristic.
Gone are the old-school plug-in DFI coupler system. It’s been replaced by a large ECU switchgear on the left handlebar with three buttons that control two engine modes (Normal and Mild) and three traction control levels (Low, Strong and Off). It also houses the kill button. It’s the same unit you see on the Honda CRF450R. The buttons’ lights are off in the standard settings but turn on when you start pushing. Holding both buttons together puts the bike into launch control mode, which shuts off once you click the transmission into third gear.
The bike’s air intake system has been reworked from beginning to end. The airbox is radically different and maintenance friendly.
You also get Kawasaki’s Rideology Smartphone App. With the app, you can fine-tune the engine character to your liking as you could with Yamaha’s early version of its Power Tuner App with a grid pattern for ignition and fueling. You also have other convenient features like a maintenance log and real-time data, including air temperature, throttle position, coolant pressure and more. You can also log your bike setup notes, such as track conditions and suspension settings.
However, one of my favorite updates is the ODI lock-on grips that replace the previous grips that were literally molded to the throttle tube. The new grips complement the new Brembo lever that operates the new Brembo front brake system. Kawasaki retained the Nissin hydraulic clutch and, surprisingly, its anorexically skinny lever.
The KX’s engine couplers have been replaced by this—a new, easy-to-use handlebar controller. It also houses the traction control adjustability and the kill button.
Let It Ride | 2024 Kawasaki KX450 Review
I was anxious to ride the ’24 KX450 for the first time. The KX450 hasn’t scored outside the top three of my shootout picks since its revamp in 2019, and I wondered if that could change with the latest, highly updated model. After riding it for the first time, I doubt it.
The most notable difference between the outgoing KX450 and the incoming is power. The 2023 KX450 wasn’t known for having that pull-your-arms-off type of power. The ’24 is no different. But power delivery is, if you can believe it, even smoother from bottom to top. There’s no real hit in the power curve. Instead, it pulls you along smoothly like a luxury sports car rather than a tricked-out hot rod. They’ve mellowed out the pop from the bottom end while extending the over-rev limit at the top of the rpm range. As a result, I could carry gears longer than before when attacking the steep uphills and long straights at Glen Helen Raceway, where I rode the bike.
Brembo is now responsible for the KX’s front braking.
No shame in my game. I admit that I always opt for the “smoother” map when riding 450cc motocrossers; 450s are just so darn fast! But with the mild map, the bike feels tame. Dare I call it a KX350?
I felt out of character, wanting actually to try the aggressive map on a 450, but I did. In the normal, “aggressive,” mode, the punchier power brought the KX to life and felt on par with other bikes in its class. Yet, the KX450 still felt manageable. With such controllable power, you can ride this bike closer to its limit. The KX450 is by no means slow. Overall horsepower is still the same, just delivery and character are smoothed out.
The easily adjustable maps and traction control are a welcomed addition to the KX, especially in the varying conditions of our test day. Rain began to fall on the deeply ripped Glen Helen soil, allowing me to put the Kawi’s traction control system to the test. You can certainly feel the differences, and it is an excellent option to have at your disposal. TC isn’t for everyone all the time, but it can be for everyone some of the time.
The rider cockpit is on point and comfortable from the get-go. It still has a square-edge seat, and the footpegs feel larger than some OEM offerings. The Renthal Fatbar has a nice, neutral bend and gels well with the overall rider triangle. Pair that with the new ODI grips, and the Kawi feels right at home from the get-go. My only complaint is the mismatched clutch and front brake levers. I got used to it, but it reminded me of the days when you’d slap on an old random lever from the toolbox so as not to forfeit your day at the track.
Even though the 2024 KX450 put on some weight, it’s still a relatively agile machine.
The KX450 feels agile despite gaining approximately five pounds (I am told). The bike seems shorter than the previous generation, which aids in its nimble character yet doesn’t seem to take away from the higher-speed stability.
The front end allows the rider to point and shoot at different lines on the track, while the rear end feels planted and glued to the ground. Side-to-side motion also required minimal effort when shifting weight or leaning the bike over in a turn. The new Brembo front brake is the icing on the cake in the handling department. Its progressive power and precise feel are a positive update for the Kawi.
Suspension seemed as sweet as ever, but Glen Helen’s soft and wet track conditions on this day weren’t ideal for putting the fork and shock to the test. As a result, all I can say is, so far, so good. The KX450’s suspension had the day off, but we will put it to work soon and will let you know.
You can just sit back and let the KX do all the work.
From what I can tell so far, though, overall, the new KX450 is a solid platform. A smooth engine inside a stable chassis is every rider’s dream, especially a vet rider’s, and the new KX450 delivers. Kawasaki engineers addressed several issues from last year’s bike, like grips, levers (well, at least 50%), and electronics, and made the bike even more rideable with the new engine. Other features like the easy-access airbox and phone app make it even easier to live with. If you’re looking for one of the smoothest and most controllable engines in the 450 class, you should keep your eyes on the 2024 KX450.CN
VIDEO | 2024 Kawasaki KX450 Review
2024 Kawasaki KX450 Specifications
| MSRP: |
$10,499 |
| Engine Type: |
4-stroke, single |
| Valvetrain: |
DOHC, 4-valve |
| Cooling System: |
Water-cooled, |
| Displacement: |
449.9cc |
| Bore x Stroke: |
96.0 x 62.1mm |
| Compression Ratio: |
12.5:1 |
| Starting System: |
Electric |
| Fueling: |
DFI with 44mm Keihin throttle body |
| Transmission: |
5-speed, w/ hydraulic Nissin clutch |
| Frame: |
Aluminum perimeter |
| Handlebar: |
Renthal Fatbar |
| Front Suspension: |
Showa 49mm inverted telescopic coil-spring fork |
| Rear Suspension: |
Uni-Trak gas-charged shock with piggyback reservoir |
| Front-Wheel Travel: |
12 in. |
| Rear-Wheel Travel: |
12.1 in. |
| Front Wheel: |
21 in. |
| Rear Wheel: |
19 in. |
| Front Brake: |
270mm, Brembo Caliper |
| Rear Brake: |
240mm, Nissin caliper |
| Rake/Trail: |
26.6°/4.5 in |
| Seat Height: |
37.8 in. |
| Ground Clearance: |
13.6 in. |
| Fuel Capacity: |
1.64 gal. |
| Weight (wet, claimed): |
248.2 lbs. |
