2021 Kawasaki KX250 Review

With more AMA Motocross and Supercross championships combined than any other manufacturer in its class, you’d be forgiven for thinking the new Kawasaki KX250 is a machine reserved solely for the off-road elite – blokes (and ladies) with a single-digit body fat percentages, flat caps and calloused hands.

But the new 2021 Kawasaki KX250 (this isn’t the return of the hulking green two-stroker: as of last year, the F is officially silent, says Kawasaki) begs to differ. Offering more power, revised ergonomics and expected mod-cons, including an electric start function and hydraulic clutch, Kawi’s mid-size fighter claims to be equally capable in the hands of a mid-level rider.

We put the new green machine to the test in Sydney last month to vouch for its mere-mortalism. The result speaks for itself.

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Up to speed

For an evolutionary update, there’s a laundry list of changes to the Kawasaki KX250 for 2021.

Priced from $11,299 (an increase of $600 over its predecessor), the 2021 KX250 offers a reworked engine promising an additional 1kW of power and a higher 14,500rpm redline (up 350rpm), the new hydraulic clutch and electric starter, additional chassis and frame components shared with the larger KX450, plus a set of new bars.

The 249cc four-stroke engine itself was the recipient of numerous changes in 2020, including the adoption of finger-follower valve train design shared with Kawasaki’s ZX-10R superbike. Finger-followers are small rocker arms that act as levers to translate the rise and fall of the cam lobes to the valve’s stem. This finger-follower valve train increases the lift of the valves and permits the cams to be much more aggressive. KTM has employed this technology since 2005.

For 2021, the engine’s additional power stems from larger diameter intake and exhaust ports, revised exhaust cam timing, revised combustion chamber design and a flatter piston crown. All told, power is said to be bolstered in both low- and mid-range revs as well as the upper echelons.

The increased rev count stems from updated valve springs with a higher spring rate.

Kawasaki joins the bulk of 250cc manufacturers in offering an electric starter for 2021. The system draws power from a lithium ion battery. All told, the starting system and its ancillaries contribute to a weight gain of 2.3kg for 2021, to 107.5kg.

The Kwaka comes with interchangeable DFI couplers to alter the engine mapping to suit different track surfaces. Changing couplers is a simple tool-free process that can be done between races, however there is no way to adjust the modes on the fly like systems from Honda, KTM and Husqvarna. There’s also a holeshot button on the handlebars for ultimate starts.

Cradling the engine – which is also a stressed member – is an evolution of the 2020 Kawasaki KX250 frame that includes more common parts with the KX450, including its swingarm. Kawasaki says the frame’s cast parts (like the shock tower mount and engine hangers) are designed specifically for the KX250.

The steering head area, main frame rails and swingarm brackets have also been revisited with a view of increasing the bike’s rigidity balance.

As before, the KX250 is suspended by a 48mm KYB inverted coil-spring fork and a KYB rear shock with dual compression adjustability, allowing separate high-speed and low-speed damping adjustment. Kawasaki fine-tuned suspension settings front and rear to match the updated chassis, as well as setting the triple clamp lower than before.

An updated 250mm (up 10mm) rear disc brake complements the KX250’s 270mm front unit, which has been augmented by the KX450’s superior front master cylinder.

Completing the 2021 Kawasaki KX250 overhaul is a new aluminium Renthal Fatbar, which is said to reduce vibration and elicit improved ergonomics.

New sensation

Our rendezvous with the new Kawasaki KX250 takes place at the new MX Dome in Sydney’s west. Appearing almost like a giant jumping castle on the horizon, this climate-controlled and air-sealed blow-up facility boggles the mind – both in terms of its sheer scale and its foreseeable electricity bill.

An added sweetener on this day is the newness of our test bike. Other than a short 10min burst on a dyno, it is fresh out of the crate and not a single scuff to its name. Kawasaki’s own mechanics are on hand to adjust rider sag and adjust personal lever preference, or the positioning of the KX250’s four-stage handlebar mounts and two-stage footpeg mounts. We elect to ride the KX as is out of the box, personalising only the positioning of the handlebar levers.

First impression is the 2021 KX250 feels decidedly slim, thanks to its revised one-piece shrouds. The cockpit feels open and accessible, factors reinforced by a relatively high-set flat seat with less natural rise to the top of the fuel tank.

Basic fit and finish feels initially good, though past experience has shown Kawi still can’t quite match it with Honda and others on panel alignment and the wear and tear of components. After a handful of laps, the bikes of numerous testers were already wearing black scuff marks from their knee braces.

However, all this fades to the back of your correspondent’s mind upon thumbing the new electric starter and waking the Kawi to life.

Expression session

Given its wealth of championship and race wins, the competition pedigree of the Kawasaki KX250 is founded. But perhaps a more redeeming and relevant feature is the ease of use for anyone that isn’t in the top 5 per cent of riders (i.e. your humble correspondent).

Full disclosure: I haven’t ridden a motocross track for a couple of years. My forearms blow up after a handful of laps and, as the pics suggest, I’m not clad in the latest and greatest riding gear.

In the presence of the Kawasaki KX250, it doesn’t matter. There’s an ease of use, lightness and predictability in the latest mid-size Kawi wrought by a balanced chassis, progressive damping front and rear and an engine that is equal parts torquey and laden with punch.

The upshot is the Kawasaki KX250 cultivates confidence among intermediate riders by providing a dynamic threshold that is more akin to the skills and speed of advanced pilots. Loads of feel and feedback are central to the Kwaka’s fluidity and ease of use.

First, the engine. Although we weren’t able to acutely explore the additional 350rpm on offer, what’s clear is the engine makes useable power across the dial. On the tight and undulating MX Dome, the four-stroke finds its natural cadence in the middling revs, at which point it provides immediacy and tractable go-forward.

What’s also clear based on our short test is that the KX250 engine rewards aggressive riding, the engine revving happily out of slower turns to produce bursts of manageable go-forward. Low RPM bursts are met with linear forward surge, without the explosiveness of the 250’s mid-range.

We tinkered with both the regular and more aggressive riding plugs, finding the latter gave an incremental boost in engine sharpness. The mapping functionality still isn’t as versatile as, say, Yamaha’s YZ250F, which offers adjustment via a free smartphone app and the ability to switch between two maps while riding. For a greater range of mapping choices on the KX250 you need to buy Kawasaki’s calibration kit.

Irrespective of that, the engine has no problem channelling its power to the at-times greasy surface underneath, offering up both high speed and low speed traction.

We can’t comment on the KX250’s gearbox or its spread of ratios, since the entire MX Dome facility is a second-gear track. That speaks to both the tightness of the circuit but also the torque afforded by the Kawi’s 249cc mill.

The new hydraulic clutch is boon, though, offering more feel than the predecessor unit and predictable modulation through the lever. As with KTM’s hydraulic units, the new system doesn’t spell the end of dreaded arm pump, but it brings a lightness that will be welcome among riders.

Elsewhere, turn-in response is predictable and front end feel is confidence-building. Work within sensible parameters and the KX250 rewards, enabling you to transition through turns and get on the gas earlier than you might anticipate.

The KX250 sits comfortably in the very small ruts that emerge mid-way through the day. We will await a more comprehensive outdoor test before delivering a final verdict here, however.

The lightness of the KX250 is most pronounced upon leaving Terra Firma. It makes small adjustments comfortably while suspended above the ground, and its 107kg mass is easy to navigate and control. Seat bouncing out of tight corners is met with predictability and composure, too.

KYB components front and rear provide reassuring and progressive damping over small-amplitude imperfections, yet feel controlled over larger hits. We occasionally came up short on the MX Dome’s smaller double-jumps, whereupon the suspension soaked up the bulk of the compression and resisted the temptation to bounce you into the next obstacle.

Dunlop rubber front and rear provides its own predictability, too, both in terms of the edge of the tyre and under full-throttle blasts. We were particularly impressed at the speed in which you can load the KX250 up through the middle of a tighter berm before giving it the berries to blast your way out.

The KX250 verdict

If our praise hasn’t already suggested it, the KX250 is a confidence-inspiring machine, and one that enamours with its ease of use, predictability and positive dynamic charm.

Perhaps the more redeeming quality is the KX250’s ability to eke performance from its rider, such is its dynamic envelope.

Until now, the KX250’s biggest shortcomings extended to minor gripes like the absence of an electric starter. Kawasaki has remedied that and more for 2021, helping the KX250 consolidate its place as the segment’s consummate all-rounder.

A wider suite of on-the-go mapping adjustability would no doubt help the KX250’s cause, but in any case, it’s clear there will be more champions in the making aboard Kawi’s 250cc machine.

Specs: 2021 Kawasaki KX250

ENGINE
Type: Single cylinder, liquid cooled, DOHC, 4-valve, four-stroke
Capacity: 249cc
Bore x stroke: 78 x 52.2mm
Compression ratio: 14.1:1
Fuel system: 44mm throttle body with dual fuel injectors
Starting: Electric

TRANSMISSION
Type: Five-speed
Final drive: Chain

CHASSIS AND RUNNING GEAR
Frame: Aluminium perimeter
Front suspension: 48mm inverted KYB coil-spring fork, 314mm of travel
Rear suspension: KYB shock, 316mm of travel
Front brake: Nissin hydraulic, 270mm single petal disc
Rear brake: Nissin hydraulic, 250mm single petal disc
Front tyre: Dunlop Geomax MX3SF, 80/100-21
Rear tyre: Dunlop Geomax MX3S, 100/90-19

DIMENSIONS AND CAPACITIES
Claimed wet weight: 107.5kg
Seat height: 950mm
Wheelbase: 1485mm
Ground clearance: 335mm
Fuel capacity: 6.2 litres

OTHER STUFF
Price: $11,299
Bike supplied by: Kawasaki Motors Australia
Availability: Now