Kawasaki's fuel-injected, liquid-cooled, DOHC, four-stroke 450cc single-cylinder engine produces 39.6 kW (53.1 hp) and 44.9 Nm (33.1 lb-ft) of torque at the rear wheel as measured on the publication's in-house dyno, ranking fifth in peak horsepower and fourth in torque. This engine delivers the highest horsepower and torque in its class from 4,200 to 5,700 rpm, while from 7,700 to 8,700 rpm, it records the lowest output in its class. The model carries an MSRP of $10,599, making it the most expensive standard 450cc motocross bike among Japanese brands, while remaining priced below its European competitors.
The KX450's engine, with its linear power delivery and low-revving character, is one of the most manageable in its class. Its power characteristics suit experienced riders, yet there's untapped potential in stock form. However, Kawasaki's free Rideology smartphone app can sharpen engine response and enhance the fun factor of the power experience. While useful, this feature isn't as intuitive as Yamaha's Power Tuner app, and it lacks a lap timer.
The Nissin hydraulic clutch provides generally good feedback with a light feel, though it is slightly vague. Shifting performance is adequate. The engine braking on the KX450 is more pronounced than most in this class, similar to the Triumph TF 450-X. It vibrates more than other Japanese competitors but less than the three Austrian bikes.
2026 Kawasaki KX450 suspension
Kawasaki was one of only two manufacturers in this shootout to equip its 450cc motocross bike with Showa 49mm coil-spring forks and a Showa shock, the other being Honda. However, while the Honda CRF450R's suspension is tuned more for performance, Kawasaki has opted for a comfort-oriented setup. The KX450's suspension offers a decent level of plushness—better than the three Austrian bikes, but not as good as the Yamaha YZ450F.
"As for the Showa suspension, I prefer Kawasaki's tuning. It feels softer and more compliant than the Honda's!" — Cody Johnston
Compared to the competitor GasGas MC 450F, which features a comfort-oriented setup designed for experienced riders, the Kawasaki comes equipped with 5.0 N/mm fork springs and a 54 N/mm shock spring. While these specs look reasonable on paper, the base settings are too soft. For faster or heavier riders and racers (around 81.6 kg / 180 lbs and above), adding fork oil or even switching to stiffer springs is almost essential. The rear shock is one of the easiest to adapt to, similar to the Yamaha's KYB shock; setting the sag to 100-105mm makes it workable right away.