Kawasaki made headlines with its Ninja ZX-4RR announcement last year. The return to the small-bore four-cylinder brought back memories of Japanese manufacturers who competed in the All Japan TT F3 Championship. This all-new model from Team Green takes inspiration from the unattainable racebikes of the late ‘80s and early ‘90s and applies it to a roadworthy sportbike in an accessible package. The 2023 Kawasaki Ninja ZX-4RR was the winner Cycle World’s Ten Best Lightweight Streetbike for 2023. It’s for a good reason. The 399cc DOHC, liquid-cooled inline four offers a rev range that is unmatched by any other lightweight motorcycle: 16,000 rpm. (Just over 15,000 in the US).
There are four riding modes: Sport (road), Rain (rain), and Rider. The first three ride modes are pre-set for power and traction controls, while Rider allows the user to select between full power or low power as well as three levels of control. A bidirectional quickshifter is also included as standard equipment. The chassis is made up of a high-tensile frame in steel, a 37mm Showa Separate function Big Piston fork, with spring preload adjustment, and an adjustable Showa balance free rear cushion shock. The 2023 Kawasaki Ninja ZX-4RR was 418 pounds before it hit our Dynojet250i dynamometer.
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On the Cycle World On the dyno test, the 2023 Kawasaki Ninja ZX-4RR generated 56.3 hp and 25.8lb.ft. torque at 11,300rpm. The 2022 KTM RC 390 is a good reference.Cycle World’s 2022 Best Lightweight Streetbike) produced 40.2 hp at 8,900 rpm and 24.4 lb.-ft. of torque at 6,900 rpm, but has a lower wet weight of 365 pounds. The 4RR’s flat torque curve and linear power delivery offer a flexible package to commuters as well as trackday enthusiasts. To get the best out of this engine, you need to keep the rpms singing beyond the midrange.