The smallest member of the Kawasaki Ninja sportsbike family started life as a 250 cc, grew to 300, and now it's had another growth spurt. Inspired by the championship-winning ZX-10R and styled accordingly, the new Kawasaki Ninja 400 sports a new engine housed in a brand new frame and sets a new example in its class.

During the last decade a whole class of sport motorcycles has withered to the point of extinction. One after another, most manufacturers have turned their backs on 600 cc supersports, in part because of dwindling demand, but also because the development costs involved are directly comparable to those of building a new liter superbike.

At the same time, the factories invested on new small and mid-sized machines that kept one eye on the entry-level clientele of Western markets, and the other on the growing appetite of Asian motorcyclists. Long after the two-stroke 125 and 250 cc GP replicas had vanished from global markets, small-capacity sportsbikes returned, this time as docile 250 four-strokes. Soon enough, these grew to 300 cc and became popular enough to give rise to a new Supersport 300 class in the World Superbike Championship (WSBK).

Kawasaki is the first of the Japanese manufacturers to take its pocket rocket to the next level by installing an even bigger engine. The new entry-level Ninja sports a brand new 399 cc in-line twin-cylinder engine that ups the performance to 45 hp (33.6 kW) and 38 Nm (28 lb-ft), compared to the 39 hp (29 kW) and 27 Nm (19.9 lb-ft) of the previous 300 cc model.

The 2018 Ninja 400 is built around a new steel trellis frame, which features shorter wheelbase and steeper rake over the previous model, in theory making for a quicker-steering bike. Surprisingly enough, it is also 8 kg (17.6 lb) lighter than the 300, tipping the scales at 168 kg (370.4 lb). Shrinking the fuel tank from 17 to 14 liters (4.5 to 3.7 gal) has undoubtedly helped in shedding some mass.

In terms of equipment, the new Ninja sports as standard Kawasaki's assist and slipper clutch, as well as Nissin's latest ABS kit. Its suspensions include new non-adjustable 41 mm front forks, similar to those used in the Ninja 650, and a rear shock absorber with five-step adjustable spring preload. Kawasaki also throws in a new front disc brake paired to a two-piston caliper, and suggests that at 310 mm in diameter it is the biggest in the class.

No information has been released on pricing and availability, and there is another important question that we hope will be answered soon. Will the Ninja 300 be dropped from the line-up, and, if so, what about Kawasaki's participation at the Supersport 300 class of WSBK?

According to the 2017 rulebook, eligibility to this class is not described in generic terms, but is rather model-specific. The current list includes the Ninja 300, so it will be very interesting to find out whether the new 400 will be allowed in its place, going up against Yamaha's R3 that is currently ruling the class.

Source: Kawasaki

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