The Ninja ZX-4RR mounts a 399 cc In-Line Four engine with class-leading performance in a compact chassis with proportions similar to smaller-displacement models. On the track or on the street, experiencing the exhilaration of the Ninja ZX-4RR’s unprecedented power, intoxicating high-rpm wail, and its sharp, nimble handling will surely awaken the dormant supersport within you.
The new 399 cc liquid-cooled DOHC In-Line Four engine pushes technological boundaries to comfortably top the 400cc class. Developed with know-how gained from other Ninja ZX models, the high-performance engine offers class-leading power and a rev-range that extends beyond 15,000 rpm.
This engine features racing-inspired technology also found on the Ninja ZX-10R. The high revs deliver a distinctive, exhilarating engine sound characteristic of a high-performance Kawasaki In-Line Four.
Allowing riders to take even greater advantage of the Ninja ZX-4R’s exhilarating engine character, the quick shifter enables clutchless upshifts and downshifts for seamless acceleration and easy deceleration.
Complementing the centrally positioned Ram Air intake, the side Ram Air duct, designed with feedback from the Ninja H2, routes air to the air cleaner box and contributes to stellar performance. Its aggressive look and intake sound add to the screaming In-Line Four experience, and visually identify the bike as one of Kawasaki’s Ninja ZX models.
Key chassis dimensions (centre of gravity position, swingarm pivot position, engine axis positions, caster angle, etc) were inspired by Kawasaki’s World Superbike Ninja ZX-10RR racer, bringing WorldSBK chassis design thinking to the 400cc class.
Designed using Kawasaki’s advanced dynamic rigidity analysis, this trellis frame made from high-tensile steel delivers the required balance of strength and chassis flex to achieve the Ninja ZX-4RR’s nimble supersport-style handling.
The Ninja ZX-4R’s two ø290 mm front brake discs and radial-mount monobloc calipers provide sure stopping power, while also offering excellent braking feel to inspire confidence both on the track and on the street.
The ø37 mm inverted fork uses SFF-BP internals to deliver both racetrack performance and everyday usability while the Horizontal Back-link rear suspension offers a progressive character. Offering increased adjustability, the Ninja ZX-4RR’s front forks include adjustable spring preload, and it features a Showa BFRC lite rear shock—the same type seen on the Ninja ZX-10R.
Naturally aggressive riding position (more forward-leaning than the Ninja 400’s, but still slightly relaxed) lets riders take advantage of the Ninja ZX-4R’s nimble handling. The fuel tank feels slim, promoting good contact with the bike, while the shape of the firm seat cushion facilitates rider weight shift during sport riding, and is comfortable for longer rides.
