2020 Kawasaki KX250 review

Lovers of two-strokes, no it’s not a misprint. Kawasaki recently released a 2020 KX250 and while that news may have activated your inner powerbands, it’s still a four-stroke – just with the ‘F’ missing from its name.

Despite the resurgence in two-stroke popularity, Kawasaki must have reasoned that two-strokes are buried so deep in history nobody needs reminding its current motocross bikes are all four-strokes.

For 2019, it was Kawasaki’s flagship motocross model, the KX450, that scored an extreme makeover, but for 2020 it was time for the smaller sibling to score a major transformation.

Headlining the updates for the 2020 Kawasaki KX250 is a new engine that not only boasts more power but a shift in that power to higher in the rev range and with a higher rev limit. Kawasaki also made a major suspension switch from the Showa Separate Function Fork (SFF) used on the 2019 KX to the highly commended and more traditional 48mm Kayaba coil spring fork.

Bikesales sampled the 2020 Kawasaki KX250 at the western Sydney test facility of suspension specialist Shock Treatment.

At first glance, it’s obvious Kawasaki has stuck with its minimalist approach from 2019 with subtle graphics on new black radiator shrouds. Apart from the black shrouds the rest of the plastics on the 2020 Kawasaki KX250 are lime green, doing away with the white number plates of the past.

It’s a shame most number plates will be covered with coloured backgrounds and numbers because the all-green looks mean. Even the plastic shock protector is green for 2020. The lack of graphics, particularly where a rider’s legs grip the bike, makes me wonder how scuffed the plastics will look after a season of motocross abuse.

The rear brake disc has swollen to an expansive 250mm, 10mm larger than the 2019 model, while the other notable feature that hasn’t changed is the kickstarter. It would’ve been great to see electric start on the 2020 Kawasaki KX250, but it seems energy and investment has been focussed on the higher-revving, more powerful engine and new suspension setup.

It’s true the maximum power of the 2020 Kawasaki KX250 lives high in the rev range, north of 10,000 rpm, but it hasn’t been a simple matter of shifting the power from down low to up high. The new engine configuration features a shorter stroke for higher rpm and a wider bore for bigger intake and exhaust valves with increased lift to flow more air.

Finger follower valve actuation, as used in the KX450, has raised the 250’s rev ceiling by 500rpm and enabled the use of more aggressive cams, both adding to top-end performance. Compression has also been raised from 13.4:1 to 14.2:1 via a new design of the short-skirted piston crown.

Top-end poke is also aided by a redesigned airbox with a shorter, tapered intake funnel, along with a larger throttle body and tweaks to the position and angle of the twin fuel injectors. Finally, changes to the exhaust system, including an overall shortening of 30mm, further contribute to high-rpm performance.

Aggression is the key

Where earlier model KX250 four-strokes, and competitors like the current Yamaha YZ250F, have strong bottom-end power to blast off the line and out of slow turns, the 2020 Kawasaki KX250 delivers a flat dose of power off the bottom. Don’t get me wrong: the KX is rideable at low revs, but there’s not a lot of action in that part of the engine room.

While low in the revs, the bike doesn’t launch out of turns when you grab a handful. That might not be a big deal for recreational riding on private property or at a local ride park, but if you’re racing to win, using the flat bottom-end to exit turns won’t do you any favours. However, if you keep the revs up and your corner speed high the 2020 Kawasaki KX250 will keep pace with the best of them.

The Kawie’s lack of low-end acceleration means riding the bike is similar to riding a 125cc two-stroke. Keep the engine singing and you’ll be rewarded with fast laps. The engine won’t bog down like a two-stroke would when it falls out of its powerband, but it won’t rocket out of turns like it does when the engine is high in the rpm.

This realisation was evident between sessions on the test track over a series of six uphill rolling jumps. While scoping out the track and getting a feel for the bike, the revs were low and the bike bounced its way from one jump to the next in an undignified fashion.

With growing familiarity with the track and machine, the rev range also ramped up and the 2020 Kawasaki KX250 suddenly came to life. Between low revs and high the Kawie has wickedly different personalities. With the engine singing at high rpm the same awkward six jumps became three sets of flowing double jumps, the bike skipping across the section with power and grace.

Kawasaki’s press information mentions the higher rev limit making it easier to tie corners together for faster lap times. That sounded like creative marketing to me, but it’s a concept that proved to be true. With the engine on song I found myself using more of the track to make straighter lines out of the turns and doing so made the whole lap flow.

A pussy-foot approach to riding the KX doesn’t yield a fast or exciting outcome, but amp up the aggression, keep the revs above 10,000 rpm and the whole show comes to life, turning a sluggish ride into a scintillating one. When ridden high in the rev range, the KX is a rocket!

In an age when most four-stroke MX bikes fire up with the press of a button, the KX is off the pace with its “old school” kickstart system. The way a bike starts might not seem like a big deal, but in a race situation if you stall the bike or the engine flames out in a crash, the speed at which you get the engine fired can make a huge difference to your finishing position.

With its increased engine compression combined with my stumpy legs I didn’t find the 2020 Kawasaki KX250 easy to start and even harder to do so with the engine in gear. To make life easier during testing I made a point of stopping on a slope so I could roll start it back to life. Unfortunately, you don’t have the luxury of choosing where you crash or stall a bike during a race.

I know I’m getting soft in my old age, but kickstarting a dirt bike also requires energy: electric start requires none. If you’re long in the legs and fit as a fiddle there’s a chance kickstarting a 250cc four-stroke won’t bother you, but if you’re like me – short and lacking fitness – I suggest you hone your kickstarting technique if you plan on racing a KX250.

The lack of electric start shouldn’t be a deal breaker for recreational riders who don’t need to fire their engines in milliseconds, but when Honda, Yamaha, Husqvarna and KTM all offer electric start racers would have to think seriously about buying a bike with an old fashioned kickstarter. I’ll be surprised if Kawie doesn’t fit the magic button to the 2021 KX250.

Kawasaki’s move from the Showa Separate Function Fork to a 48mm Kayaba coil-spring fork should be a welcomed one. The Showa system may have worked well for experienced suspension technicians but difficult to dial in for the average rider. The Kayaba fork is a proven, dependable unit with impressive adjustability to suit a variety of tracks, riders and skill levels.

With its increased power output, Kawasaki reasoned the bike needed stiffer fork and shock springs. The bike is more powerful for 2020, but that doesn’t mean it will be ridden any faster by riders below a pro level, so I’m not sure that logic makes complete sense. Pro level riders or riders north of 70kg might appreciate the stiffer springs, but most will benefit from downgrading the spring rates.

During my initial laps of the test track, the back of the bike felt high and the rear end felt loose. The track was dry and the dirt loose, but I expected more grip from the Dunlop MX3S tyres than I was getting.

The team from Shock Treatment checked the ride height and wound off the spring preload to achieve an ideal ride height for my weight. The resulting excess static sag highlighted the need for a softer rear spring for a rider in the 60kg bracket.

The five-minute adjustment delivered better balance and increased grip levels. Knowing the bike was over sprung for my weight I expected harsh handling. The Kayaba package was firm but in no way hard or harsh.

In fact, the firmness of the suspension proved to be a confidence builder. The test track featured a variety of jumps, including doubles with steep take-off ramps and single jumps with flat landings.

The double jump with the steepest take-off had me spooked. The steep face would shoot the bike high, so I knew I’d have to hit it with speed. The KX handled every other heavy, flat landing so beautifully I decided to trust the Kayabas, hit the doubles with speed and overjump the landing ramp.

As predicted, the KX soaked the hard landing smoothly, remaining completely poised and settled, immediately ready to attack the doubles that followed. The KX doesn’t collapse on hard landings or rebound unpredictably. It’s an incredible, confidence-inspiring feeling.

The bike also tracked predictably through high-speed ruts that had formed in the wet and baked hard in the heat. The way the bike settles in turns is yet another way the KX inspires confidence. Through a downhill, off-camber, rutted turn the Kawie seemed to settle even before I did. It was like I was having to keep up with the readiness of the bike. Speaking of turns, the KX feels sharp and precise when changing direction. It’s agile in the turns and stable on the straights. What a combination!

Late model dirtbikes offer a range of adjustability and tunability so riders of different sizes and skill levels can refine their rides. The 2019 KX250 ticks some boxes to make the bike more versatile, however Kawasaki’s competition is surging ahead with exciting technology, leaving the KX in their dust.

The Kawie offers great adjustability in its ergo layout with multi-position handlebar mounts and adjustable footpeg heights. In the handling department the fork and shock are fully adjustable and a couple of clicker changes on the fork or shock make a notable difference.

Power-wise, 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 I found the differences between couplers underwhelming.

In contrast, the Yamaha YZ250F’S engine mapping can be altered via a free smartphone app with an adjustment range to make significant changes to the bike’s power characteristics. Yamaha riders can also switch between two maps while riding. For a greater range of mapping choices on the KX250 you need to buy Kawasaki’s calibration kit.

Honda, KTM and Husky also offer handlebar-mounted buttons to change engine mapping on the fly, while Suzuki now offers Wi-Fi tuning capability similar to the Yamaha. As with previous model KX250 four-strokes, the current model has the handlebar-mounted holeshot button for better traction out of the starting gate.

There’s a lot to like about Kawasaki’s 2020 KX250, unless you were expecting it to be a two-stroke, that is. Riders who bleed green will love the handling and adjustability of the new Kayaba suspension, while the top-end poke is impressive. Kawie riders will also appreciate the affordability of the new green machine, up to $1500 cheaper than its competitors.

But if Kawasaki really wants to win over more of the buying public it needs to get on pace with its rivals by adding electric start and smartphone engine mapping for 2021. The KX would also be a better bike if some of that increased top-end power was shifted back to the bottom end so a wider variety of riders can improve their lap times, not just the pros.

ENGINE
Type: Single cylinder, liquid cooled, DOHC, 4-valve, four-stroke
Capacity: 249cc
Bore x stroke: 78 x 52.2mm
Compression ratio: 14.2:1
Fuel system: 43mm throttle body with dual fuel injectors
Starting: Kickstart

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, 310mm 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: 105.2kg
Seat height: 948mm
Wheelbase: 1480mm
Ground clearance: 333mm
Fuel capacity: 6.4 litres

OTHER STUFF
Price: $10,699
Bike supplied by: Kawasaki Motors Australia
Availability: now