Kawasaki Ninja ZX-4RR vs. Ninja 650 Country Road Test 2024

The Greens (we're not talking politics here) do a lot of things right, especially with their sporty models (of which Kawasaki has quite a few). They hit the mark visually with their customers. A venomous green, an aggressive headlight design, and a few graphic accents from the WSBK machines make you feel like a true superbiker, even if it's "just" a comparatively everyday-friendly Ninja 650.

But that's exactly what it's all about; a certain level of comfort should not be missing on an everyday sports bike like the Ninja 650. A true supersports bike, on which you are known to lie more than sit, is simply too uncomfortable for many for daily rides. So, the Ninja 650, compared to its naked bike sister Z650, gets slightly lower handlebars, but a much more efficient fairing, making it less of a supersports bike and more of a sport touring bike, where it excels.

The engine fits this profile perfectly, with its 68.2 HP at 8000 RPM and 65.7 Nm of torque at 7000 RPM, the parallel-twin naturally makes a better figure on the country road than on the race track. And this is exactly where the crucial difference lies compared to the true supersport Ninja ZX-4RR, whose inline-four with just 100 cc per cylinder is cut from a completely different cloth. Several testers have already reported to me about the race track capabilities, and I can perfectly understand that it must be a hell of a lot of fun to wind out this 400 cc rocket to 16,000 (!) RPM on the track.

It is astonishing to me how well this green arrow functions even on country roads. 77 horsepower suggests an acceptable performance, but the proud 14,500 RPM at which this power is delivered suggests a completely unusable rev range for country roads. Additionally, the low torque of only 39 Newton meters at an absurdly high 13,000 RPM could make one expect the Ninja ZX-4RR to perform like a moped in the four-digit RPM range! But far from it, the manageable Ninja ZX-4RR revs up almost confidently from the bottom, the electronic engine management does an excellent job and gets the best out of the small displacement. The available rev range is record-breakingly wide anyway, even if one might wish for a bit more grunt at the bottom, it pulls nicely in the middle, really kicks off at around 8000 RPM, and the rubber band doesn't snap until 16,000 RPM!

Surprisingly pleasant is also the seating position; the small ZX-4RR is naturally sportily dimensioned, and the Ninja 650 is definitely more comfortable, but for a true supersports bike, it is still exceptionally comfortable. The clip-ons are not mounted quite as low on the fork, so the load on the hands is unexpectedly low, and the pegs are at a height that does not necessarily require the body measurements of a small parade racer.

That both Kawas score very similarly in handling is not really surprising when you consider that both rely on a steel frame, a relatively narrow 160 rear tire, and the Ninja 650 weighs only 4 kilos more than the ZX-4RR, which is actually quite heavy at 189 kilos. However, some of those kilos are excellently invested in a high-quality chassis. While the Ninja 650 relies on a conventional fork without adjustment options at the front and a mono shock with adjustable preload at the rear, the Big Piston USD fork of the Ninja ZX-4RR allows for preload adjustment, and the rear mono shock even allows for rebound, compression, and preload adjustments. Together with the finer responsiveness, this makes the small ZX not only better on the race track but also better on twisty roads when riding spiritedly.

Similarly, the brakes on the ZX-4RR, while not overly large with its dual 290mm discs at the front, are far more effective when combined with the radial four-piston monoblock calipers than the larger 300mm dual discs with two-piston calipers on the Ninja 650. This was to be expected, as the Kawasaki Ninja ZX-4RR is a true supersport, whereas the Ninja 650 only has the look. However, the higher-quality setup of the ZX-4RR is also quite suitable for everyday use, as it can be regulated very precisely.

Finally, the Ninja ZX-4RR also scores more points in electronics compared to its simpler sibling, the Ninja 650. While the 650 comes well-equipped with ABS, traction control, LED lighting all around, and a TFT color display with connectivity, which are all essential features in this class nowadays, the smaller Ninja ZX-4RR adds even more. In addition to the features mentioned for the Ninja 650, the ZX-4RR boasts four riding modes (Sport, Road, Rain, and Rider), a dedicated race track graphic with special functions for the TFT display, and a delightful quickshifter with a blipper. This, combined with the unparalleled wind-out potential of the 4RR, highlights the sporty soul of this mini-supersports bike.