Since Kawasaki unveiled the ZX-25R in June, 2020, small-capacity supersport riders outside Asian markets have been chomping at the bit for the model. Those same fans breathed a sigh of relief when rumors of a potential ZX-4R model surfaced in May, 2021. However, the ZX-4R airwaves went dead for over a year. Now, new information suggests that Kawi could roll out the red carpet for the new green machine in 2023.
As previously reported, we expect Kawasaki to base the ZX-4R on its existing ZX-25R machine. The four-cylinder supersport would retain the same frame, but its quarter-liter mill would benefit from a displacement bump to 399cc. While the ZX-25R pumps out 44 horsepower, the extra capacity would certainly increase the ZX-4R's power potential as well.
Japan media outlet Autoby reports that the ZX-4R would also earn a double-disc front braking system and wider-section rear tire to handle that extra oomph. Additionally, the supersport could also sport a different exhaust system in order to keep the bored-out powerplant within current emissions regulations.
The new exhaust, fatter rear donut, and supplementary caliper and rotor should also add a few pounds to the ZX-25R's 397-pound wet weight, but aside from those key differences, the two small-bore screamers would share much of the same equipment. Unlike the ZX-25R, though, Vehicle Identification Number (VIN) decoder information issued by the U.S. National Highway Traffic Safety Administration (NHTSA) confirms that Team Green will ship the ZX-4R outside of Asia.
Using the ZX400SP and ZX400PP designation, Kawasaki is prepping two ZX-4R variants for release in the U.S. in 2023. According to Motorcycle’s main moto detective Dennis Chung, industry-standard distinguishes 2023 models with the final ‘P’ digit, while the ZX-4R's ‘S’ and ‘P’ penultimate letters most likely correlate to ABS and non-ABS trims. Unfortunately, we won’t be able to confirm any of these predictions until the brand officially reveals details of its upcoming inline-four. Still, as small-capacity supersport fans ourselves, we can’t wait for the ZX-4R to finally break cover.