2023 Kawasaki ZX-6R Review

Admin · August 25, 2023

Kawasaki has never been shy about its intentions for the ZX-6R. The goal? Build a middleweight sportbike that makes just as much sense for the street rider as it did the track day enthusiast or racer. (Kevin Wing/)

Images of Kenan Sofuoğlu flash through your head as you throw a leg over Kawasaki’s ZX-6R. This is a very different bike than the winningest World Supersport rider of all time rode to his final three Supersport World Championship titles. But it makes all the right noises and feels just as purposeful as that bike. That’s a hard thing to come by these days. And it’s only getting harder, as manufacturers continue to rethink their approach to middleweight supersport bikes.

Lucky for sportbike fans, Kawasaki hasn’t given up on the class. In fact, it has doubled down and invested in an updated platform for 2024. Before jumping on that machine, we decided it was time to refamiliarize ourselves with the current-generation ZX-6R, one of just three inline-four 600s left on the market. If you’re looking to buy new, your only other options are the Honda CBR600RR and Suzuki GSX-R600.

Mind you, the ZX-6R is not technically a 600, as Kawasaki uses a larger-displacement 636cc engine with more robust low-end and midrange. It’s a small difference on paper, but part of an important strategy for Kawasaki, who always claimed the current-generation 6R bike was built with the street rider in mind, just as much as it was the trackday enthusiast or racer.

The 2023 ZX-6R’s design dates back to 2019, but still looks plenty sharp. The 2024 model will have an updated look. (Kevin Wing/)

About the Bike

The rest of the modern ZX-6R package—all-new in 2013 and updated just once, in 2019—hints at Kawasaki’s efforts to maintain the racing pedigree that the ZX namesake was built on. The bike rolls on a Showa Big Piston Separate Function Fork (BP-SFF), uses Nissin Monoblock front brake calipers, and has a more expansive electronics package than the competition. Said package includes two power modes, three-level (plus off) Kawasaki Traction Control (KTRC), and an electronic quickshifter.

Styling was updated in 2019, Kawasaki at the time restyling the tail cowl, front cowl, and windscreen to better align the bike with its Ninja siblings. A couple of other niceties were added at the time, including LED lights, a reshaped seat, plus adjustable clutch and brake levers. All things that contribute to a still relatively modern-looking motorcycle.

Winglets? What are those? Simplicity feels welcomed here. (Kevin Wing/)

Important to mention is that the 2024 ZX-6R has an even more modern look; in addition to updating that bike’s engine to meet modern emissions regulations, Kawasaki revamped that bike’s front and side cowls, plus updated the LED headlights and windscreen. The 2024 model also gets a 4.3-inch TFT display and updated ride modes, including Sport, Road, Rain, and a customizable Rider mode.

Riding Impressions

That TFT display is greatly missed when riding the 2023 ZX-6R, even if the analog tachometer and LCD display work as they should, offering all the information you need, including selected ride mode and traction control setting. We left these settings alone for the better part of our track and street riding, as the bike doesn’t make enough power to warrant going from “Full” to “Low” power mode. And traction control level 1 offered enough of a safety net for most situations.

Adjusting ride modes, traction control settings, and navigating menus is managed by a switch on the left clip-on. Notice the span-adjustable levers, a nice touch. (Kevin Wing/)

That’s not to say we don’t appreciate power modes and what adjustability you do have on the 2023 ZX-6R; this is an especially great feature for newer riders who are getting up to speed and want to gradually increase power output. But the relatively narrow use case and limited need is important to understand, as it can potentially explain why middleweight bikes aren’t being updated as much as other models, where those technologies pay bigger dividends.

Our 2023 ZX-6R made 108.4 hp at 13,200 rpm and 45.8 lb.-ft. of torque at 10,900 rpm when strapped to our in-house Dynojet 250i dyno. That’s in line with expectations for a bone-stock middleweight supersport bike, but also only tells half the story, as the ZX-6R is more user-friendly than a traditional 599cc inline-four in around-town riding. Consider the extra 37cc an “easy” button for the casual street rider. That’s especially true when leaving stoplights; the extra bottom-end grunt means you don’t have to get overly aggressive with the throttle and clutch when the light turns green.

If you’re going to ride a middleweight sportbike around town, best to do it on one with a little extra pep in the midrange. The downside to the ZX-6R, at least in city-street riding, is that the clip-on position is quite aggressive. (Kevin Wing/)

The benefits don’t end there, as that extra midrange helps the bike jump off tight corners with more intensity when riding in the canyons or at the track. Part of our testing included side-by-side riding with a Suzuki GSX-R600, and the ZX-6R’s added midrange made it easy to pull away from the Suzuki through a series of tight corners. The benefits are more than just in time and space, however, as the 6R’s beefier midrange allows the Kawasaki-mounted rider to be more relaxed. There’s a broader trigger, and it’s easier to pull. That requires less focus.

None of this is to take away from the fact that you’re still on a middleweight supersport and can’t expect to really get going until the tach needle sweeps past 9,000 rpm. At that point, everything we’ve come to know and love about an inline-four supersport holds true; the engine is free revving and raucous, but still with a sense of smoothness that you won’t find on something like the V-twin-powered Ducati Panigale V2.

Nissin Monoblock calipers offer strong, consistent braking performance that’s plenty strong enough for track riding but not overwhelming for street riding. (Kevin Wing/)

While Kawasaki is proud of the added flexibility that the engine offers street riders, it has made less of a compromise when it comes to the rider triangle and chassis. This is obvious from the second you throw a leg over the ZX-6R, as you sit more on top of the bike, and the heavily angled clip-ons are mounted quite low, putting you in an attack position. This is to be expected from a sportbike, but stands out when riding back to back with the Suzuki GSX-R600, which has a more relaxed rider triangle.

The bike is razor-sharp and nimble, particularly in fast chicanes where the rider has to quickly get the bike from one side of the tire to the other. But there’s a catch, as that quick handling makes the bike somewhat twitchy when inputs are too abrupt or a bump in the track catches you off guard. Suspension is plush enough to absorb track surface chatter, however there is significant dive under heavy braking, leading to a “pitchy” sensation. Suspension changes and proper sag setup help remedy this, but don’t alleviate it all together.

The combination of flexible, 636cc engine and sporty chassis makes the ZX-6R an absolute blast to ride in the canyons. (Kevin Wing/)

This bike has two sides to it. There’s the more relaxed side made possible by the engine with its broad range of power, and a more serious side that comes courtesy of the pointed chassis. This is what allows the ZX-6R to cater to street and track riders alike. Those who want to push the ZX-6R will find a chassis that’s performance minded and fully up for the challenge. Be ready to work on suspension setup though, as it takes time to get the Showa Big Piston Separate Function Fork dialed in.

It’s hard to spin the tire up on the ZX-6R, but traction control offers peace of mind when inching closer to that point, like at the end of a long trackday when the tires are worn, or when the weather takes a turn for the worse, mid-ride. This is not the latest lean-angle-sensitive technology and you can sense the lack of precision compared to the latest-generation systems found elsewhere in the motorcycling world, which operate in a more narrow window thanks to the additional information gathered by multiaxis IMUs.

This system does the job it was tasked with, cutting power before things go sideways, and it does so in an only slightly unobtrusive way, with a cut that’s aggressive, but not enough to completely compromise your drive. The system is not overly cautious either, and still lets you have some fun before stepping in. Would a newer, more technologically advanced system aid in quicker lap times when running around at an aggressive pace? Probably. But for those who aren’t racing, this TC gets the job done.

The ZX-6R chassis is as it was since the bike was overhauled in 2013. There’s racebike DNA here, which is to say the bike is agile, but feels on-edge when pushed. Finding the right suspension settings helps bring some balance to the package. (Jeff Allen/)

The same can be said for the quickshifter. There are more refined systems on the market, but the ZX-6R shifter works as intended, offering smooth, clutchless upshifts at almost any rpm, with just a slight hiccup during low-rpm, half-throttle shifts, like what you might make when cruising from one stoplight to the next. So, no, it’s not perfect. But in this case, good enough.

Final Thoughts

It might seem like hyperbole to suggest that the middleweight supersport bike could go away, and silly to suggest that we should be happy with “what’s left,” but if Yamaha pulling the legendary R6 from its lineup taught the motorcycling world anything, it’s that legends can die.

Lucky for those who appreciate the dedicated performance of an inline-four middleweight, Kawasaki is fighting to make sure the ZX-6R doesn’t suffer the same fate. And after spending time with the bike, we’re glad it is. There’s still something very special about finding the limits of a middleweight supersport bike, and being able to push that bike’s limits without feeling like you’re one small mistake away from high-siding yourself to the moon, as can happen on a 180 hp literbike.

At the same time, the ZX-6R offers more technology than most of its remaining competition in the States (a fully modern CBR600RR is available in just a few countries), and has more performance than the new parallel-twin sportbikes that manufacturers are turning their attention toward. It’s not just a fun package that rekindles memories of yesteryear, but a fun and capable package. Period.

2023 Kawasaki ZX-6R ABS Specs

MSRP:	$11,999
Engine:	DOHC, liquid-cooled inline-4; 4 valves/cyl.
Displacement:	636cc
Bore x Stroke:	67.0 x 45.1mm
Compression Ratio:	12.9:1
Transmission/Final Drive:	6-speed/chain
Cycle World Measured Horsepower:	108.4 hp @ 13,200 rpm
Cycle World Measured Torque:	45.8 lb.-ft. @ 10,900 rpm
Fuel System:	DFI w/ 38mm Keihin throttle bodies (4)
Clutch:	FCC slipper/assist
Engine Management/Ignition:	TCBI w/ electronic advance
Frame:	Twin-spar aluminum
Front Suspension:	41mm inverted Showa SFF-BP fork, rebound, compression damping, spring preload adjustable; 4.7 in. travel
Rear Suspension:	Bottom-link Uni-Trak w/ gas-charged shock, piggyback reservoir, compression, rebound damping, spring preload adjustable; 5.9 in. travel
Front Brake:	Nissin radial-mount 4-piston calipers, semi-floating 310mm discs w/ ABS
Rear Brake:	1-piston caliper, 220mm petal disc w/ ABS
Wheels, Front/Rear:	Cast aluminum
Tires, Front/Rear:	Bridgestone Battlax S22; 120/70-17 / 180/55-17
Rake/Trail:	23.5°/4.0 in.
Wheelbase:	55.1 in.
Ground Clearance:	5.1 in.
Seat Height:	32.7 in.
Fuel Capacity:	4.5 gal.
Average MPG:	41 mpg
Cycle World Measured Wet Weight:	432 lb.
Contact:	kawasaki.com