A Mid-Displacement Supersport

The Ninja ZX-6R bolsters Kawasaki’s mid-range sportbike presence with much the same race-tastic tendencies as its larger-displacement siblings, just in a smaller package. It goes far beyond the looks; the factory stuffed a four-cylinder plant inside the windtunnel-tested body panels with a full electronics suite to help keep it all under control. However, this doesn’t necessarily make the “6R” suitable for beginners, but rather an appropriate first or second upgrade, or perhaps as a funbike for weekend warriors. Today I want to take an in-depth look at this Ninja and see how it fares against a comparable model from another of the Big Four.

Continue reading for my review of the Kawasaki Ninja ZX-6R.

  • 2015 Kawasaki Ninja ZX-6R ABS
  • Year:
    2015
  • Make:
  • Model:
  • Engine:
    Four-stroke, liquid-cooled, DOHC, four valves per cylinder, inline-four
  • Transmission:
    6-speed
  • Energy:
    Digital Fuel Injection (DFI)
  • Displacement:
    636 cc
  • Top Speed:
    143 mph (Est.)
  • Price:
    12699
  • Price:

Kawasaki Ninja ZX-6R Design

2015 Kawasaki Ninja ZX-6R ABS
- image 795391
Kawi means for the 6R to be taken as a serious mid-size machine and not just another pocket-sized crotch rocket.

Kawi means for the 6R to be taken as a serious mid-size machine and not just another pocket-sized crotch rocket. Toward that end, the factory leads off with a pointed cowl similar to its big brother, the ZX-10R. It sports the same low coefficient-of-drag for optimal penetration with a bubble screen that shapes the rider’s pocket, and you have to tuck in tightly to get it, but the short bars mount directly to the top of the tripleclamp so they pull you right up into the Superman position.

The 6R features dual headlights within eye-like recesses in the upper fairing with the front turn signals ensconced in the lip of the intake cowl in a bid to keep drag to a minimum. A central vent provides a straight shot to the intake system for the incoming air, and due to the ram-air effect can produce a higher volumetric efficiency than a normally-aspirated engine, and all with a concurrent increase in power. Naturally, the radiator benefits from the usual cowl-scoop down below that wash heat from below the panels out the vents to reintegrate with the slipstream.

A 4.5-gallon fuel tank defines the upper lines with a taper down to a very narrow waist and a flange up top to form a pocket to pull your legs in and out of the pressure as part of its drag-reducing efforts. The tail runs uphill opposite the low nose for a stance that is typical of supersports, and though it does mount a pillion pad and a pair of fold-up, subframe-mount passenger footpegs, the design of the rear end is influenced more by performance concerns than human-cargo comfort.

Gotta’ say, I’m not a fan of the mudguard that clutters up the rear end; a nice hugger and side-mount tag would really look boss. Oh well, aftermarket guys’ kids need to eat, too.

Kawasaki Ninja ZX-6R Chassis

2015 Kawasaki Ninja ZX-6R ABS
- image 795389
The 6R delivers a supremely agile ride that is eager in the corners and makes for quick flicks and reversals, just the sort of handling you want for some peg/knee/elbow-dragging fun.

Make no mistake, this is a proper race-type bike whose commitment to performance goes much more than skin deep. The 6R rides with a cast- and pressed-aluminum, perimeter-style frame that embraces the engine like a jewel in a setting and keeps the structural weight to a minimum. A short/steep steering head sets the rake at 23.5-degrees with four inches of trail for a supremely agile ride that is eager in the corners and makes for quick flicks and reversals, just the sort of handling you want for some peg/knee/elbow-dragging fun.

The stems come off the top shelf on the 6R; Showa’s 41 mm SFF-BP forks float the front end on 4.7-inches of travel and Kawi’s Uni-Trak system uses a coil-over monoshock with 5.3-inches of travel. Both ends come with the full trinity of adjustments — preload, compression- and rebound-damping — so you can dial the ride quality right in. Curb weight clocks in at only 427.8 pounds, so the mass-saving efforts do have the desired effect, but there is still the potential for producing great amounts of energy with this machine and the brakes reflect that.

Up front, a pair of 310 mm discs and four-pot, monobloc (billet) Nissin calipers take care of business, while a single-piston anchor bites the 210 mm disc out back with Kawasaki’s own anti-lock brake system (KIBS) to make sure you can safely get the max out of the binders. The hubs are symmetrical at 17-inches around and lined with a 120/70 up front followed by a 180/55 to give you nice, fat contact patches with which to work. If you ain’t down with any sort of ABS coverage ’cause you’ve got mad skills, then you can opt for a non-ABS version at checkout.

Frame: Aluminum perimeter
Front Suspension / Wheel Travel: 41 mm inverted Showa SFF-BP fork with top-out springs, stepless compression and rebound damping, adjustable spring preload/4.7 in
Rear Suspension / Wheel Travel: Bottom-link Uni-Trak® with gas-charged shock, stepless compression damping adjustment, 25-way adjustable rebound damping, fully adjustable spring preload/5.3 in
Rake / Trail: 23.5°/4.0 in
Front Tire: 120/70ZR17
Rear Tire: 180/55ZR17
Front Brakes: Dual 310 mm petal discs with dual radial-mounted, Nissin 4-piston, monobloc calipers (ABS model: w/KIBS ABS
Rear Brakes: Single 210 mm petal discs with single-piston caliper (ABS model: w/KIBS ABS)

Kawasaki Ninja ZX-6R Drivetrain

2015 Kawasaki Ninja ZX-6R ABS
- image 795394
You get just about all the streetwise fandanglery, but it falls short of true race-day capabilities with a lack of launch control and clutchless shifting.

The stage is set, now let’s get to the star of the show; the compact four-cylinder powerplant. Kawi crams 636 cc into the mill with a decidedly oversquare 67 mm bore and 45.1 mm stroke and pistons that have the skirts all but completely removed to reduce reciprocating mass and deliver quicker revs. Compression is high with a sizzlin’ hot 12.9-to-1 ratio and a taste for pump champagne, but that’s to be expected really.

A quartet of 38 mm Keihin throttle bodies feed the monster and enable a number of electronic rider aids to include Power Modes and Traction Control. The Power Mode feature lets you set the engine for full power or tune it down to 80-percent with a tamer throttle response and the three-mode traction-control system intervenes with timing and induction adjustments when wheel-slip is detected. In other words, you get just about all the streetwise fandanglery, but it falls short of true race-day capabilities with a lack of launch control and clutchless shifting to name a few, at least on the stock version.

The 6R’s clutch is of the slip-and-assist variety so not only do you benefit from the lighter pull, but you also get some anti-hop protection to prevent excessive backtorque from diminishing the traction at the rear wheel. A cassette-style transmission brings things back into more race-tastic territory, and it comes with a synergistic design that works with the engine to centralize the weight of the shafts and keep it low in the frame.

How does it all shake out? Well, the factory claims 52.1 pound-feet of torque at 11,500 rpm, so there’s plenty of grunt to be had, you just have to really wind it up to access all of it.

Engine: 4-stroke, 4-cylinder, DOHC, 16-valve, liquid-cooled
Displacement: 636 cc
Bore x Stroke: 67.0 x 45.1 mm
Compression Ratio: 12.9:1
Fuel System: DFI® with 38mm Keihin throttle bodies (4) and oval sub-throttles
Ignition: TCBI with digital advance
Transmission: 6-speed, return shift
Final Drive: Sealed chain
Electronic Rider Aids: Kawasaki Traction Control (KTRC), Power Mode, ABS model w/ Kawasaki Intelligent anti-lock Brake System (KIBS)

Kawasaki Ninja ZX-6R Pricing

2015 Kawasaki Ninja ZX-6R ABS
- image 795390

A non-ABS 2018 ZX-6R will set you back a total of $11,699, and if you want that KIBS protection you’ll have to shell out $12,699 MSRP. As for the color; the good news is that you won’t have to pay extra for the paint package you want but the bad news is that if you don’t want Mettalic Matte Fusion Silver over Metallic Flat Spark Black, you’re SOL.

Warranty: 12 Month Limited Warranty (optional Kawasaki Protection Plus™ 12, 24, 36 or 48 months
Color: Metallic Matte Fusion Silver/Metallic Flat Spark Black
Price: $12,699 (w/o ABS: $11,699)

Kawasaki Ninja ZX-6R Competitors

2015 Kawasaki Ninja ZX-6R ABS
- image 795395
2014 - 2019 Honda CBR600RR
- image 795386
The 6R has more electronic rider aids for the same amount of money at the checkout.

For my head-to-head, I decided to go to one of Kawasaki’s longtime domestic competitors and I wound up with Honda’s CBR600RR as a machine that is definitely in the same market as the Ninja. The CBR carries just a bit more in the way of body panels, and I’m not a fan of the stick-out turn signals but Honda still wins big in the aesthetics department because of the smooth overall appearance that eases the edges that the Ninja so proudly displays. That’s just a personal preference, of course. I know that many of you like that sort of thing.

Honda espoused the same school of thought in its engine layout; the CBR’s 599 cc plant runs as a transverse-mount inline four, and it delivers 48.7 pound-feet of torque to fall just a skosh short of the Ninja’s 52.1 pounds o’ grunt. Honda embraces the ram-air concept with a version of its own, but it seems that the Red Riders completely cede the electronic warfare to Kawi as the CBR runs with no electronic rider aids. That’s a pretty big hit in the current market.

Honda toes the line in the suspension department though, the 41 mm front forks and rear monoshock have the full spectrum of adjustments, so neither gain anything here. At the checkout these two finish neck-and-neck. Honda asks $11,799 for its non-ABS CBR600RR and another grand for the ABS version, just a single Benjamin more than the Ninja across the board, so you can forget about using price as a decider here.

He Said

“For me, Kawi wins hands-down because of the electronic rider aids. Even if you think you don’t need them, there comes a time in every rider’s life that they might wish they had some safety net under them. Looks aside, the Ninja wins easily, and it brings something to the table for the mid-size racers wannabes among us.”

She Said

My wife and fellow motorcycle writer, Allyn Hinton, says, “This feels surprisingly tame at lower speeds than I would have thought. Overall, it just doesn’t feel like a supersport. That’s not necessarily a bad thing, and it’s just my opinion. If you have a Ninja 300 and you’re looking to upgrade, you might want to look at something else, ’cause this just feels like a 300; or if you have a 300 and you just want a little more engine, this could be your Huckleberry. The bike loves corners and is very flickable, as you’d expect. So, yeah, I might say entry level for this one.”

Kawasaki Ninja ZX-6R Specifications

Engine & Drivetrain:
Engine: 4-stroke, 4-cylinder, DOHC, 16-valve, liquid-cooled
Displacement: 636 cc
Bore x Stroke: 67.0 x 45.1 mm
Compression Ratio: 12.9:1
Fuel System: DFI® with 38mm Keihin throttle bodies (4) and oval sub-throttles
Ignition: TCBI with digital advance
Transmission: 6-speed, return shift
Final Drive: Sealed chain
Electronic Rider Aids: Kawasaki Traction Control (KTRC), Power Mode, ABS model w/ Kawasaki Intelligent anti-lock Brake System (KIBS)
Chassis:
Frame: Aluminum perimeter
Front Suspension / Wheel Travel: 41 mm inverted Showa SFF-BP fork with top-out springs, stepless compression and rebound damping, adjustable spring preload/4.7 in
Rear Suspension / Wheel Travel: Bottom-link Uni-Trak® with gas-charged shock, stepless compression damping adjustment, 25-way adjustable rebound damping, fully adjustable spring preload/5.3 in
Rake / Trail: 23.5°/4.0 in
Front Tire: 120/70ZR17
Rear Tire: 180/55ZR17
Front Brakes: Dual 310 mm petal discs with dual radial-mounted, Nissin 4-piston, monobloc calipers (ABS model: w/KIBS ABS
Rear Brakes: Single 210 mm petal discs with single-piston caliper (ABS model: w/KIBS ABS)
Dimensions & Capacities:
Overall Length: 82.1 in
Overall Width: 27.8 in
Overall Height: 43.9 in
Ground Clearance: 5.1 in
Seat Height: 32.7 in
Curb Weight: 427.8 lb
Fuel Capacity: 4.5 gal
Wheelbase: 54.9 in
Details:
Warranty: 12 Month Limited Warranty (optional Kawasaki Protection Plus™ 12, 24, 36 or 48 months
Color: Metallic Matte Fusion Silver/Metallic Flat Spark Black
Price: $12,699 (w/o ABS: $11,699)

Further Reading

Honda CBR600RR

2014 - 2019 Honda CBR600RR
- image 795382

See our review of the Honda CBR600RR.

Kawasaki Ninja 300

2015 - 2017 Kawasaki Ninja 300
- image 679365

See our review of the Kawasaki Ninja 300.

All images featured on this website are copyrighted to their respective rightful owners. No infringement is intended. Image Source: kawasaki.com, honda.com

Press release
What do you think?
Show Comments
Motorcycle Finder: