KAWASAKI KX450X: FULL TEST

Kawasaki has officially returned to the closed-course competition off-road racing market with the introduction of their 2021 KX450X model. Based off the successful KX450 motocross model, Kawasaki expanded that platform by adding features the off-road market prefers, including softer suspension, different gearing, off-road-specific tires, different power characteristics, 18-inch rear wheel and more.

The KX450X has plenty of power to handle just about anything the rider feels like doing. Tight technical trails and wide open desert terrain is no problem.

Well, technically, Kawasaki never left the off-road racing market altogether, but their factory-level racing effort did see an enormous decrease in the last decade or so. In 2019, Kawasaki launched their all-new KX450 motocross model that combined some proven features of the past and some brand-new features that had never been seen on a Kawasaki production model before. An all-new frame, redesigned engine, improved braking system, hydraulic clutch and the return of a Showa spring fork were the major highlights that got the off-road world paying attention again. We think the decision to move away from an air-fork system and back to a spring-fork version was huge for off-road riders and racers. Fast-forward two years and Kawasaki has a successful off-road race team venture on both sides of the United States, and for 2021 announced the KX450X model. If you are familiar with the KX450 motocross model, then you don’t have a lot to learn; it utilizes the exact same chassis and engine platform, so it’s easier to focus on what is actually different between the KX450X and KX450 models than it is to list the overall features.

Kawasaki’s 2021 KX450X is good foundation for building a great off-road race or trail machine, you just need to add a few key bolt-on items.

Powerplant-wise, the KX450X has the same updates internally that the MX model got for 2021 with an all-new clutch that Kawasaki is calling a coned disk spring, which is similar in design to the version used by KTM that they call the DDS clutch. This is still controlled by Nissin hydraulic components. Kawasaki is trying to achieve a lighter clutch pull and better clutch-engagement range to help improve control. This system uses larger-diameter clutch plates and different friction-plate material with new offsets. On the MX model, we noticed this did improve overall rider feel, and when fully released under power, it locked out harder, improving traction under power. Just like the MX models, the X model uses a colored coupler system (green, black and white) with pre-programmed maps, which can also be reprogrammed will custom maps as well. The couplers can be changed out easily and do make noticeable differences. The KX450X comes standard with the black coupler installed, this is the least aggressive map and made the bike feel slow and heavy, so we changed it out for the green coupler (standard on the MX model). This gave us a livelier power all around, making it feel less weighed down.

 

The KX450 MX and off-road versions are identical internally engine wise.
The KX450X comes with a few more plastic protection items than the MX model like a skid plate, rear rotor guard and a rear caliper guard.

Handling has been a Kawasaki KX450 strong point since the introduction of the latest chassis in 2019, and with the KX450X utilizing that chassis in its entirety with slightly different valving and spring rates in the Showa suspension components, it’s no surprise stability is still a strong point. The feel is softer overall that all the DB test riders noticed it right away, especially on GP- or MX-style courses, but this does not affect stability or predictability of the machine. Faster or 200-plus-pound riders will definitely need to stiffen the suspension up all around for competition use.

A kickstand is key for trail riding and the peg mounts on the 450X are steel instead of aluminum like the MX model.

2021 KX450X FEATURES

  • Softer fork springs and valving
  • Softer shock springs and valving
  • 18-inch rear wheel
  • Dunlop AT81 tires
  • Plastic skid plate
  • Rear disc and rotor guards
  • 51-tooth rear sprocket
  • Black mapping coupler
  • Kickstand
  • Smaller rear brake rotor(compared to 450MX)
The black coupler comes installed from the factory on the 450X but test riders preferred the green coupler. This is what comes standard on the MX model and just livens up the power delivery a bit.
An 18 inch rear wheel and off-road specific Dunlop AT81 tires are standard issue on the KX450X.

THE BOTTOM LINE
Overall, the staff here at Dirt Bike is happy to see Kawasaki return to making models specifically for off-road use, and we think the off-road community will respond with sales across the board because the KX450X is a great starting point. All 450s are a handful on tight trails, and the KX450X is no exception, but if you want the power for open spaces, there has to be a sacrifice somewhere.

The KX450X is probably one of the easiest 450s to control in tight technical situations for the average rider due to its smooth power delivery and class-leading power down low.  Handling-wise, the KX450X starts off with a stable chassis, and Kawasaki did a nice job finding a middle-ground setting. And just like with most bikes, it’s important to set it for the type of riding you do the most. If that’s tight technical trails, then expect it to be really soft on GP- or MX-style courses, because you can’t have your cake and eat it too. With Kawasaki’s minimalistic approach overall, the 2021 KX450X makes a good starting point for an off-road machine. It just needs a few more bolt-on items for it to be completely ready to tackle the elements.

HITS
• Easy-to-use power
• Adjustability
• 18-inch rear wheel
• Kickstand
• Skid plate and plastic protection items
• Hydraulic clutch
• Electric start
• Side-access airbox
MISSES
• Small fuel tank
• Non-O-ring chain
• No handguards

2021 KAWASAKI KX450X SPECS

Engine type: Electric-start, four-valve DOHC, four-stroke
Displacement: 449cc
Bore & stroke: 96.0mm x 62.1mm
Fuel delivery: 44mm Keihin EFI
Fuel tank capacity: 1.6 gal.
Transmission: 5-speed
Lighting coil: No
Spark arrestor: No
EPA legal: No
Weight, no fuel: 238 lb.
Wheelbase: 58.5”
Ground clearance: 13.4”
Seat height: 37.4”
Front tire: Dunlop AT 81  80/100-21
Rear tire: Dunlop AT81 120/80-18
Fork: Showa 49mm, adj. rebound,  comp./12.0”
Shock: Showa, piggyback, adj. preload, comp., rebound/12.0”
Country of origin: Japan
Price: $9299

Importer www.kawasaki.com

 

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