TOP FEATURES
All-New In-Line Four Engine
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.
High-revving Performance
With a redline beyond 15,000 rpm indicating its screaming potential, 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.
Enhanced Power. Distinctive ZX Look.
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.
Redefining the 400cc Supersport Category
Kawasaki takes 400cc-class engine performance to a new level, achieving an unprecedented 56.7 kW (77 PS) of power with Ram Air. The howl of the engine as it revs beyond 15,000 rpm adds to rider exhilaration. A quick-revving nature and direct throttle response are complemented by a flexible character that offers strong low- to mid-range torque for city riding, as well as screaming high-rpm power ideal for sport or track riding.
World Superbike Inspired Chassis Design
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.
Trellis Frame with Optimised Rigidity Balance
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-4R’s nimble supersport-style handling.
Dual Front Disc Brakes
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.
High-Grade Suspension
The Ninja ZX-4R’s 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.
Ergonomics for Control and Comfort
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.
Supersport handling, stopping power and ride character
Fierce Ninja ZX Styling
Befitting the most powerful machine in the 400cc class, the Ninja ZX-4R’s aggressive Ninja styling exudes a fierce aura of restrained power and explosive action.
TFT Colour Instrumentation with Circuit Mode
The 4.3” all-digital TFT colour instrumentation with selectable display modes (Normal, Circuit) clearly displays the most pertinent information, whether on the street or on the track. Circuit Mode shows the gear position, lap times, and rpm above 10,000 more prominently.
Enhance your motorcycling experience
Bluetooth technology built into the instrument panel allows connection to smartphones via the “RIDEOLOGY THE APP” smartphone application, enabling riders to access instrument functions for an enhanced motorcycling experience.
*RIDEOLOGY THE APP is not intended for use during vehicle operation. Only use RIDEOLOGY THE APP when the vehicle is not being operated and it is safe to do so. 
All-LED Lighting
From its twin headlights to its Ninja ZX-10R-inspired taillight, all lighting on the Ninja ZX-4R is LED.
Kawasaki Traction Control & Power Modes
Four integrated riding modes (Sport, Road, Rain, or the manual-set Rider) make it simple to select a level of traction control and power mode to suit the current riding conditions.
Ninja ZX-4RR only feature
Dual-Direction Kawasaki Quick Shifter
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.
High-Grade Package with High-Class Styling
Technical Data / Specifications
| Power | |
|---|---|
| Maximum Power | 55.0 kW {75 PS} / 14,500 rpm |
| Maximum Power with Ram Air | 56.7 kW {77 PS} / 14,500 rpm |
| Maximum Torque | 37.6 Nm {3.8 kgfm} / 12,500 rpm |
| Engine | 4-stroke In-Line Four |
| Displacement | 399 cc |
| Bore x Stroke | 57.0 x 39.1 mm |
| Compression Ratio | 12.3:1 |
| Valve System | DOHC, 16 valves |
| Fuel System | Fuel injection: ø34 mm x 4 |
| Ignition | Digital |
| Starting | Electric |
| Cooling | Liquid-cooled |
| Lubrication | Forced lubrication, wet sump |
| Transmission | 6-speed, return |
| Primary Reduction Ratio | 2.029 (69/34) |
| Gear Ratio: 1st | 2.929 (41/14) |
| Gear Ratio: 2nd | 2.056 (37/18) |
| Gear Ratio: 3rd | 1.619 (34/21) |
| Gear Ratio: 4th | 1.333 (32/24) |
| Gear Ratio: 5th | 1.154 (30/26) |
| Gear Ratio: 6th | 1.037 (28/27) |
| Final Reduction Ratio | 3.429 (48/14) |
| Clutch | Wet multi-disc, manual |
| Final Drive | Chain |
| Perfomance | |
| Frame | Trellis, high-tensile steel |
| Front Suspension | ø37 mm inverted fork (SFF-BP) with spring preload adjustability and top-out springs |
| Rear Suspension | Horizontal Back-link, BFRC lite gas-charged shock with piggyback reservoir, compression and rebound damping and spring preload adjustability, and top-out spring |
| Front Wheel Travel | 120 mm |
| Rear Wheel Travel | 124 mm |
| Rake | 23.5° |
| Trail | 97 mm |
| Steering Angle (L/R) | 35° / 35° |
| Front Tyre | 120/70ZR17M/C (58W) |
| Rear Tyre | 160/60ZR17M/C (69W) |
| Front Brake/s | Dual semi-floating ø290 mm discs |
| Front Caliper/s | Dual radial-mount, monobloc, opposed 4-piston |
| Rear Brake | ø220 mm disc |
| Rear Caliper | Single-piston |
| Details | |
| Dimensions (LxWxH) | 1,990 x 765 x 1,110 mm |
| Wheelbase | 1,380 mm |
| Road Clearance | 135 mm |
| Seat Height | 800 mm |
| Curb Weight* | 188 kg |
| Fuel Capacity | 15 litres |
| Model Code | ZX400SSFAN |
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