2021 Kawasaki KX450X and KX250X First Look (8 Fast Facts)

July 7, 2020

Capitalizing on the 2020 dirt bike sales boom, Kawasaki is jumping into the cross-country motorcycle racing market with the all-new 2021 Kawasaki KX450X and KX250X.

Both are based on the latest versions of their motocross equivalents, with changes designed to make the X duo work better in the off-road environment. Let’s take a look at these two new models and what makes theses KXes also Xs.

2021 Kawasaki KX250X for sale — 2021 Kawasaki KX250X

1. The motors of the Xs are the same as the KX motocrossers. The only difference is that the Xes come with the coupler that uses the mildest engine tuning option, while the MX bikes use the medium engine tuning option. However, like the KX MXers, the Xs come with all three couplers so you can plug in whichever powerband works for you. If you want more sophisticated engine tuning options, the Xs are compatible with the optional KX FI Calibration Kit from Kawasaki Genuine Accessories.

2. The Xes have different gearing than the motocross bikes. While the ratios are off-road specific, they Xs retain the five-speed configuration. The 2021 Kawasaki Xs also get one extra tooth on the rear sprocket.

3. The KX450X and KX250X share the same frame, just as the MX bikes do.

4. The suspension on each X is the same units as on the MX versions, but with different tuning. Both Xs have the clickers set differently from the equivalent MX bikes—the 450 uses Showa and the 250 goes with KYB. The KX450X gets softer springs at both ends, while the KX250X has softer fork springs with the same shock spring.

5. Per standard off-road practice, the Xs get 18-inch rear wheels. Both use the highly regarded Dunlop Geomax AT81 rubber, with the KX450X going with a 120/90, with the KX250X running a slightly narrower 110/100 rear tire.

6. The 2021 Kawasaki KX Xs get model-specific front brake pads.

7. The Xs get a plastic skidplate between the lower frame rails, as well as a kickstand.

8. You’ll find the 2021 Kawasaki KX450X at your dealer any day now. The KX250X should arrive by the end of July.

2021 Kawasaki KX450X (and KX250X) Specs

ENGINE

Type: Single-cylinder four-stroke
Displacement: 449cc (KX250X: 249cc)
Bore x stroke: 96.0 x 62.1mm (KX250X: 78.0 x 52.2mm)
Compression ratio: 12.5:1 (KX250X: 14.1:1)
Starting: Electric
Fueling: EFI w/ 44mm Keihin throttle body w/ dual injectors
Transmission: 5-speed
Clutch: Hydraulically actuated w/ coned-disc spring
Final drive: Chain

CHASSIS

Frame: Aluminum perimeter
Handlebar: Renthal Fatbar
Front suspension; travel: Compression- and rebound-damping adjustable Showa 49mm inverted fork; 12.0 inches (KX250X: Compression- and rebound-damping adjustable KYB 48mm inverted fork; 12.4 inches)
Rear suspension; travel: Linkage-assisted fully adjustable Showa piggyback reservoir shock; 12.1 inches (KX250X: Linkage-assisted fully adjustable KYB piggyback reservoir shock; 12.4 inches)
Tires: Dunlop Geomax AT81
Front tire: 80/100 x 21
Rear tire: 120/90 x 18 (KX250X: 110/100 x 18)
Front brake: Semi-floating 270mm Braking petal disc w/ dual-piston Nissin caliper
Rear brake: Single 240mm Braking petal disc w/ single-piston Nissin caliper

DIMENSIONS and CAPACITIES