The new ZX-4RR sets the bar for the lightweight sportbike segment.
The North American racing community can’t be happier with the arrival of the Kawasaki ZX-4RR for multiple reasons. It is the first and only small-displacement inline-four sport bike officially arrived in the United States and Canada. Although the small-displacement “mini” superbikes are not a new concept, as almost all Japanese manufacturers have entries a few decades ago, the North American riders did not have the appetite to own one back then, so we couldn’t get one.
The time has changed, and people eventually learned to start slow and small, so that’s the main reason why the small-displacement sport bikes are still very popular as a daily rider, or a track machine. The biggest problem was no matter how capable they were, North American riders always saw them as beginner bikes, not something to own proudly for the rest of their lives. The new ZX-4RR is here to change the perception, as it can be appealing to both beginner and experienced riders.
The Looks & Details
We will need to forgive many riders for mistaking the ZX-4RR for the other Ninja models, especially the Ninja 400. For an untrained eye, there are lots of similarities, but when you get closer, the differences can be seen much easier. Both bikes come with Kawasaki Racing Team colour, graphics, and traditional Ninja body lines, but the front fascia is almost entirely different.
The most obvious difference is the ZX-4RR has the ram air intake hole located right under the windscreen, but there are other giveaways like the dual brake discs and lower handlebars – those are the goodies you would find in a much more expensive and faster ZX-6R.
Speaking of handlebars, the ergonomics is surprisingly forgiving for large adults. At 6’1″, I did not have any issues, and the bike did not feel cramped at all. The ZX-4RR offers slightly more aggressive riding geometry than the Ninja 400, but not as aggressive as bigger 600cc entries. Thanks to the relatively low seat height, the bike is very accessible for shorter adults. Most smaller Kawasaki models tend to be better fit for shorter adults, taller riders usually need more seat height for a more comfortable ride, but that is not the case here with the ZX-4RR.
The build quality and available tech are quite impressive for the price range. All physical controls feel sturdy, and plastic trims do not feel flimsy. You still get the nice “beginner-friendly” perks like adjustable clutch and brake levers, slipper clutch, safety features like traction control, and full LED lighting front and back. There are also premium features such as dual-direction Quick Shifter, a 4.3-inch TFT screen with smartphone connectivity and a dedicated app that shows a lot of information about the bike and the ride – that’s something we aren’t used to seeing in this segment.
The TFT screen works very well and shows a lot of information. There are two different screen layouts, one for daily riding, and the other for the track. You can see your lap times, and the layout is completely different, showing only what’s necessary on the track, and nothing else. The fonts are big enough, super easy to read and do not look complicated.
What is complicated is how you interact with the screen. If you are not coming from another Kawasaki product, you really need to take your time to understand how it works. You need to use physical buttons located on the left side of the handlebar, but there are also two physical buttons located under the TFT screen. The buttons under the screen are not labelled, so you have to look carefully to find them.
As a previous Kawasaki owner who reviews all types of bikes regularly, I still have to take my time and remember how it works. For the most part, it is a one-hand operation to access the basic information, but some features like the “Settings” screen require you to use both hands. Once you get used to it, it is not a deal breaker, but there could have been an easier way to implement it.
The Specs & Experience
It is not easy to see the engine as it is hidden behind the fairings. The North American ZX-4RRs are slightly nerfed which can still push 56 horsepower peaking at 11,500 rpm, which is still a respectable number to begin with, and significantly more than its sibling, the Ninja 400. However, the rest of the world gets the same bike with 74 horsepower and the same torque figure at 26.5 lb-ft and the engine can rev up to 16,000 RPM, showing the engine’s potential if you do the right modifications.
Although for some reason you will not be able to find the horsepower or torque figures on Kawasaki Canada’s website, they let you know that the engine is restricted due to the noise regulations without sharing any numbers to avoid any misunderstanding. Both the US and Canadian market gets the restricted versions, so the brand leaves it to the rider to decide if they want to keep the bike restricted or enjoy the full potential at the risk of voiding the warranty.
As you expect from a 4-cylinder engine, it is butter smooth, and it wants to rev all day. The peak torque is available closer to the redline. The downside is that there is no pulse below 8000 RPM, so you really need to be on top of the engine and keep the revs preferably at 10,000 RPM to get a decent amount of torque to move, especially at higher speeds. Either way, if you want to experience the 4-cylinder character, this is the cheapest and the safest choice, as there is a much less chance to lose your license on a public road compared to something like a 600cc sport bike and it will run happily on an 87 octane gas all day long.
The engine is not the only difference, the ZX-4RR comes with higher-tier components to make it a better track-oriented sport bike. The most important addition would be the suspension, the ZX-4RR comes with the Showa suspension setup. The front forks only allow you to adjust the preload, but it is still really good considering the bike costs just below $11,000 CAD. On the other hand, the rear shock is fully adjustable, and having that flexibility to adjust the compression and rebound without switching aftermarket parts is what makes the ZX-4RR appealing to the audience.
It might not be the perfect choice for Ontario’s long and boring highways, but it offers surprisingly good wind protection at higher speeds. However, the ZX-4RR really shines when you take it to your favourite backroads or track. The bike wants to be ridden at the limit no matter if you are going straight or not, and it feels 100% confident even if you push it to its limits. The front end is very sharp and responsive, the bike wants to lean all day long.
The ZX-4RR is slightly heavier than other small displacement entries as it has 2 more cylinders and higher-tier components, but it does a pretty good job hiding the excessive weight. The bike teaches you how to carry the speed better. The powerband is so predictable, smooth and forgiving, as a result, it gives you more confidence to get on the throttle earlier at corner-exit.
The Verdict
I really appreciate that Kawasaki has brought the ZX-4RR to North America. That was something I would only expect from Kawasaki – the brand loves to think outside the box and brings experimental products that the other brands usually do not dare to attempt. In a market where budget-oriented small-displacement machines are only aiming beginners, the new ZX-4RR can also be appealing to more experienced riders and it can be a game changer for the right audience.
The Ninja 400 would still be the ideal choice for beginners who want to have fun as an everyday sport bike, but the new ZX-4RR is the right choice if you want to go all-out on track or your favourite backroad, as it is a brand new platform built from the ground up for performance. As a result, it is the only option in this segment that offers a unique experience for the price.
Engine | 399cc, liquid-cooled, inline 4-cylinder, DOHC |
Max Power | 56 hp @ 11,500 rpm |
Max Torque | 26.5 lb-ft @ 11,000 rpm |
Front Brakes | Dual four-piston calipers with 290mm discs |
Rear Brakes | Single piston caliper with 220mm disc |
Weight | 414 lbs – 187 kg |
Fuel Capacity | 3.96 gallons – 15 L |
Seat Height | 31.5 in – 800 mm |
Base Price (2023) | $10,999 (CAD) |
Website | www.kawasaki.ca |