Kawasaki ZX-6R Ninja Homologation Special Edition

Pound for Pound, the Mightiest Middleweight Sportbike in History

Technological tour de force. That’s the only way to describe the original Ninja® 600 sportbike of 1985. Packing a liquid-cooled 16-valve inline-four (the first ever in a middleweight streetbike), wraparound twin-spar frame, anti-dive fork and aesthetics snatched right from the Grand Prix circuit, the original ZX600-A1 was a dominant, bigger-than-life middleweight.

Apparently, some things never change.

The ZX™-6R carries that tradition of middleweight dominance to a staggering level (one that would’ve blown minds in 1985). And in today’s ultra-competitive 600 supersport market, where technology, racetrack success and streetbike acumen can change dramatically year by year, that’s saying a lot. Don’t believe us? Then ask the many top-level magazines and web sites that picked the current-spec ZX-6R as Best Middleweight. It was an absolutely dominating 600 shootout performance – and one sure to be replicated due to the ZX-6R’s track-honed DNA and seamless all-around capability.

That DNA begins with a 16-valve, DOHC inline-four engine that’s everything a top-shelf middleweight powerplant should be: supremely powerful, smooth, and blessed with hammer-like reliability. Critics everywhere agree the ZX-6R runs and performs like a larger-displacement motorcycle, and one that packs a rolling chassis that out-handles and out-suspends all others. It’s a perfect combination for street riders, track day junkies and racers alike, a flexibility that helps explain its many 600 comparo victories.

It all starts with the ZX-6R’s jewel-like engine, a 599cc assemblage of everything Kawasaki knows about powerplant building, and the result of untold hours of testing and refinement garnered from dyno room to racetrack and back again. Squeezing big power from small displacement has been a Kawasaki forte for many years, from the 350cc A7 Avenger to the 500cc H1, and from that first Ninja 600 to this latest ZX-6R, class leading power is a Kawasaki sportbike birthright.

And there’s more than peaky top-end power, too. The engine’s dual cams, 16 valves, 13.3:1 compression and 38mm throttle bodies produce the sort of smooth low-end and mid-range power that make dealing with traffic, surface streets and everyday riding a much more agreeable affair. Add to that superb throttle response and liquid-smooth control feel and you have a supersport motorcycle with commuting manners that easily match its phenomenal racetrack prowess.

Much of this smooth, rheostat-like power delivery is achieved through outstanding combustion efficiency. Cylindrical guides in the top of the airbox guide the fuel charge into the intake funnels directly to reduce buffeting and improve cylinder filling. Advanced cylinder head porting slams the air/fuel charge into and out of the combustion chamber post-haste, while high-current secondaries in the ignition coils provide hot, consistent spark at all rpm for maximum combustion impact. The engine’s mid-range performance also benefits from double-bore velocity stacks with inlets at two different heights, special-profile pistons with low piston-ring tension for reduced friction, and advanced cam chain guides for the highest degree of cam-chain stabilization.

This ultra-strong midrange power not only provides arm-stretching drive out of corners. It also offers unparalleled controllability and the sort of precise throttle control that pays big dividends when making mid-corner power adjustments while stringing a set of corners together on a snaky backroad or while negotiating that tricky set of turns at your favorite racetrack.

In keeping with its racing heritage, the ZX-6R employs a cassette-type transmission that greatly simplifies gearing changes at the track, reducing set-up time and allowing more time for riding. A high-tech slipper clutch – hardware usually found only on high-end racebikes – allows quick, effortless downshifts when diving into slower corners from big speed without upsetting the chassis.

Chassis control, of course, is the other half of the 600 supersport equation, and the ZX-6R once again dominates the field with its class-exclusive Big Piston Front fork, fully adjustable shock, ideal engine placement, optimum frame rigidity and the very latest in mass centralization.

The Ninja ZX-6R’s lean physique is fundamental to its superior handling, with every component carefully scrutinized for minimal weight. For instance, the intake resonator box and supports for the instrument panel and mirrors are unitized with the enlarged – to optimize intake volume – ram air duct, both of which contribute to weight savings and improved rigidity. Camshafts are made of lightweight chrome-moly steel, while magnesium engine covers also help shed pounds. Internal engine parts such as transmission, oil pump and starter gears are carefully engineered for maximum strength and minimal weight.

If less weight is great, top-shelf suspension technology to control it is even better, and the ZX-6R packs plenty. A perfect example is the ZX-6R’s revolutionary Showa-built BPF (Big Piston Front fork) front suspension, which is one large technological step beyond the cartridge-type fork used on other 600s. The magic behind the Big Piston fork is its larger-diameter internal piston, which allows a reduction in damping pressure for smoother action and better front end feedback – especially under braking and initial corner turn-in. Additionally, the BPF eliminates many of the internal components used in a cartridge-type fork, simplifying construction and resulting in a lighter overall fork weight. The result is more control and better feedback, just what you need while ripping through your favorite right-hander during a track day, or tip-toeing along that rain-slicked backroad on your way home from work.

Suspension out back is just as advanced, and includes a gas-charged shock with dual-range (high- and low-speed) stepless compression damping, 25-way adjustable rebound damping and fully adjustable spring preload mated to a bottom-link Uni-Trak® system.

Kawasaki’s acclaimed triple petal disc brake package – with radial-mount calipers up front – is as refined and powerful as ever. Highly rigid four-piston calipers and 300mm petal-type rotors provide awesome power and excellent feel at the front wheel. The 220mm rear petal-type disc features a pedal coaxially mounted with the footpeg for increased mid-stroke braking efficiency and optimum pedal feedback. Its master cylinder reservoir mounts forward of the swingarm, freeing space around the footpeg, reducing parts and contributing to weight savings. It all adds up to unflappable composure under braking, and helps provide the precise control and feel that allows supersport racers to enter corners harder – and everyday riders to slow things down comfortably and controllably.

To better capitalize on this advanced level of light weight and precise control response, the 6R’s ergonomics have been fine tuned to enhance feedback from bike to rider and vice versa. The seat-peg-bar relationship places the handlebars close to the rider and angled for a highly intuitive riding position. The fuel tank cover is flared just so around its top edge, providing a large contact patch and contributing to excellent rider feedback – similar to the new ZX-10R. A narrow rear sub-frame and seat leading edge provide a slim, highly flexible riding position for moving around the bike, as well as a shorter reach to the pavement.

A highly refined fairing and one-piece front fender provide excellent aerodynamics and airflow to the radiator, along with superb wind protection for the rider and minimal crosswind buffeting. An inner rear fender mounted above the swingarm also reduces turbulence and helps keep the back of the motorcycle aerodynamically clean. The ZX-6R’s instrument panel provides plenty of at-a-glance information, while a race-spec adjustable twin-tube Öhlins steering damper with relief valve completes the track-ready package.

It’s all here: power, handling, light weight, advanced technology and typical Kawasaki reliability – exactly what you need to tame the racetrack, the mean streets – or both.