This more than adequate street bike really shines on the track.
Only a handful of 400-cc fours have trickled into Canada over the last few decades, from Honda (CB400F Super Sport, CB1), Suzuki (Bandit 400) and Yamaha (FZR400). Their high-revving engines, light weight, nimble handling, and exclusivity have since made these rare machines desirable among collectors, and they have developed a sort of cult following in North America. While Kawasaki has produced 400-cc inline-fours for other markets, especially its home market — where licensing is more stringent for larger-displacement motorcycles — none of them have ever made it to Canada, other than perhaps as individual import models, for collectors.
That has changed this year, as Kawasaki joins the 400 club with the introduction of the 2023 Kawasaki Ninja ZX-4R and ZX-4RR. We’re focusing primarily on the latter, which we rode exclusively at the technically challenging Thunderhill Raceway Park in California, though we also rode the 4R briefly on the road.
Like its bigger Ninja stablemates, the ZX-4RR features aggressively angular styling, and a ready-to-pounce, nose-down attitude. Unlike its supersport brethren, however, which are all built around aluminum frames, the ZX-4RR utilizes a steel-trellis frame design. Steering geometry is on the supersport side of the spectrum, with a rake angle of 23.7 degrees, 97 mm of trail, and a 1,380 mm wheelbase. The bike is relatively light, at 188 kilos with its 15-litre fuel tank full. It boasts a slightly more relaxed riding position than a true supersport machine, and it is roomier than one would expect from a 400-class bike. Seat height is 800 mm.
The frame cradles an entirely new, 16-valve, 399-cc liquid-cooled inline-four that is fed by a ride-by-wire fuel-injection system. Adjustable traction control is standard, with three levels of intervention, and it can be shut off. The bike has four selectable ride modes (Rain, Road, Sport, and Rider), as well as two power modes: Low, with soft throttle response and limited output, and High, with a more aggressive throttle and full power. Maximum power is slightly neutered, however, but more on that later.
Three of the ride modes feature preset throttle mapping, and preset traction-control levels from low to high intervention. Rider mode is configurable: engine parameters can be set independently and traction control can be turned off.
A 4.3-inch TFT colour display comprises the instrument panel, through which ride-mode selection and other functions are controlled. You can connect to your smartphone via Bluetooth and use Kawasaki’s free app, Rideology the App, to access…