400cc 4-cylinder Kawasaki Ninja ZX-4R could be launched in 2023


Kawasaki may be working on a Ninja ZX-4R, a 400cc, 4-cylinder sports motorcycle, according to rumors published by the German website motorrad.

According to them, two new Kawasaki models have been registered in the USA (but not yet confirmed), the ‘ZX400 PP’ and the ‘ZX400 SP’, with an engine also registered with the information ‘399cc, 4 cylinders’. They believe that one of the bikes could be the 4-cylinder ZX-4R, which arrives to rescue the memories of the 1989 ZXR 400.

Rumors of a ZX-4R have been circulating for a while, especially after the launch of the ZX-25R in Indonesia in 2021, a motorcycle with a 250cc 4-cylinder high revving engine, as it can revs up to 17,500 rpm.

The 250cc model has a maximum power of up to 50.3 hp at 15,500 rpm. So, the ZX-4R is expected to have around 70 hp, as the 1989 model had 62 hp and, with modern technology, it would be possible to extract a little more, even with more restrictions on pollutant emissions.

kawasaki ninja zx-25r
2023 Kawasaki Ninja ZX-25RR

Anyway, for now it’s still just rumors but, apparently, a new 4-cylinder motorcycle from the Japanese brand is in the oven. Now we have to wait for more information in the coming months.

How is the Ninja ZX-25R

Kawasaki launched the Ninja ZX-25R in Indonesia in 2021, a sports bike that arrived with a 250cc, 4-cylinder engine capable of revving over 17,000 rpm. It was developed for Asia, mainly Indonesia and Japan.

The 250cc model closely resembles the Ninja ZX-6R in terms of design, with very similar fairings and angles. This new design first appeared on the Ninja 400 in 2017, with aggressive styling and a modern, high-class design inspired by the larger supersport motorcycles in the Ninja family.

In Indonesia, it is offered in three versions: ZX-25R ‘standard’, ZX-25R ABS SE (model with everything in the ZX-25R plus Quick Shifter) and the ZX-25RR (top of the line with everything from the ZX-25R ABS SE plus ZX-10R rear suspension and adjustable front suspension).

Finally, the highlight of the model is the 250cc 4-cylinder in-line engine with liquid cooling, which is capable of generating up to 50.3 hp of maximum power at 15,500 rpm and 23Nm / 2.3 kgfm of torque at 14,500 rpm. According to the brand, this engine is capable of revving up to 17,500 rpm.

kawasaki ninja zx-25r
2023 Kawasaki Ninja ZX-25R ABS SE

Technology is not lacking

In terms of technology, the ‘small’ ZX-25R brings many items usually present only in larger and more sophisticated models.

In the ZX-25R ABS SE and ZX-25RR versions, there are the following items:

  • Assist and slipper clutch
  • ECO indicator
  • electronic throttle body
  • KQS (Kawasaki Quick Shifter)
  • KTRC (Kawasaki Traction Control)
  • power modes
  • ABS brakes
  • ‘Horizontal Back-Link’ rear suspension
  • Colored TFT digital panel
  • Smartphone connection

In addition, in all versions, the front suspension is 37 mm USD (Upside Down) Showa SFF-BP (Separate Function Fork – Big Piston), being adjustable in the ZX-25RR, and a 310 mm semi-floating front disc.

Anyway, the 2023 Kawasaki Ninja ZX-25R is sold in Indonesia for from Rp 105,000,000 (approximately US$ 6,700). The top-of-the-line 2023 Kawasaki Ninja ZX-25RR version starts at Rp 129,900,000 (approximately US$ 8,300). There is no forecast for other countries.

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photos: Kawasaki


Marcelo Souza

Author, Editor and Administrator of the MotoNews World website, graduated in Accounting, passionate about motorcycles and technology.

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