Kawasaki ZX-6R Ninja

The ZX-6R gets magnesium engine case covers, lighter cams and various other mods that make it 10kg lighter than the previous model. Improved combustion efficiency and the usage of double bore velocity stacks is supposed to smoothen out the power delivery and boost low- and mid-range power on this Kawasaki.

The new Ninja also get a slipper clutch, cassette-type six-speed gearbox, a brand-new exhaust system, revised chassis with a new two-piece aluminum subframe and revised ram air intake.

Big changes on the suspension front include Showa's new Big Piston Front (BPF) 41mm USD fork, which is fully adjustable and features a large-diameter internal piston that’s supposed to reduce the effects of damping pressure and eliminating the heavier internals found in cartridge-style forks. The result, say Kawasaki, is improved front end feel and reduced turn-in effort. A new Öhlins steering damper has also been added to the bike.

The ZX-6R’s rear suspension remains the same as before – Kawasaki’s Bottom-Link Uni-Trak with gas-charged shock – and is fully adjustable for compression and rebound damping. There are twin 300mm petal-type brake discs at front, with radial-mount four-piston calipers. The rear brake is a single 220mm disc with single-piston caliper.

Key Feature

- New leaner physique with a major reduction in weight and improved power delivery offer more precise control, lighter handling and better acceleration

Lightweight engine
- Camshafts are now made of SCM - saving approximately 400g
- Lightweight magnesium engine covers are standard and save approximately 610g over aluminum units
- Revised top injector mounting plate saves approximately 80g
- Narrower transmission gears and revised gear dog shape provide a 170g weight savings, without compromising rigidity
- Oil pump and starter gears are machined to use less metal, shedding approximately 70g
- New inlet pressure pulse monitor enables deletion of the cam angle sensor, further contributing to engine weight reduction
- Coolant reservoir relocated and redesigned, the new shape and shorter tube save approximately 150g
- Revised and relocated heat pads contribute another 170g to weight savings
- Reshaped secondary air passages through the cylinder head contribute to more efficient cleaning of exhaust emissions
- Cassette-type transmission makes it easy to quickly swap gear ratios, reducing set-up time at the track

Increased mid-range performance
- New double bore velocity stacks feature inlets at two different heights, increasing performance in both the mid- and high-rpm ranges
- Increased durability from optimized cam nitriding and tappets enable high-load cam profiles, which improve overall performance
- Pistons have new profiles and improved crown finishing
- Molybdenum coated piston skirts reduce friction and help with engine break-in
- Piston rings with less tension reduce mechanical loss
- Revised cam chain guides stabilize chain motion, further reduce mechanical loss
- New exhaust collector layout contributes to improved low and mid-range performance while maintaining high-rpm performance

More precise throttle control
- Cylindrical guides added to the top of the air cleaner box ensure more accurately sprayed fuel mist from the secondary injectors into the intake funnels, improving combustion efficiency
- Longer throttle bodies increase the distance between oval sub-throttles and round main throttles 10mm, yielding a smoother transition, which reduces inlet turbulence and increases efficiency
- Revised cylinder porting delivers improved cylinder-filling and scavenging
- New ignition coils have 12% greater secondary coil current for improved combustion efficiency, adding to the improved performance

Lightweight chassis
- The sub-frame is a 2-piece aluminum die-casting consisting of a front and rear section
- The new lightweight sub-frame is very narrow, for a compact and slim rear end
- Intake resonator box and supports for the instrument panel and mirrors are unitized with the Ram Air duct, contributing to weight savings and increased rigidity
- Frame brackets revised to reduce overall number of parts, which also contributes weight savings.
- New throttle housing material saves approximately 30g

Revised chassis balance and mass centralization
- Revised frame stiffness around the swingarm pivot and the rear engine mounts optimizes front-rear rigidity balance
- Engine is mounted with a steeper cylinder bank angle. Rotated around the output shaft, the engine’s CG is 16mm higher
- New exhaust layout with a short side muffler lowers weight previously located under the seat
- An exhaust pre-chamber further contributes to mass centralization

Ergonomics and chassis feedback
- Seat-pegs-bar relationship was adjusted slightly, with the handlebars moved closer to the rider and turned in slightly for a more intuitive riding position
- Fuel tank profile is more flared around its top, similar to the ZX-10R, providing a larger contact patch which contributes to improved rider feedback
- Slim, waist on fuel tank makes it easy for the rider to grip the tank with his knees or to hang off in turns
- Front to back, the new seat is shorter, allowing the rider to shift his body farther back on the rear seat step, helping to reduce rider fatigue
- Steeper rake angle quickens steering response and enhances communication from the front tire
- Relocating the rear brake master cylinder reservoir forward of the swingarm mount frees up space around the footpeg, enabling a reduction of parts and contributing to weight savings

Lower seat height
- New rear sub-frame is narrower, making it easier to reach the ground
- Front of seat is narrower and seat height is approximately 10mm lower, for a slimmer riding position and a shorter reach to the pavement

Advanced suspension
- ZX-6R features the first production-use of Showa’s new Big Piston Front fork (BPF) design
- The BPF eliminates many of the internal components used in a cartridge-type fork, simplifying construction and resulting in lighter overall fork weight
- The large-diameter of the BPF’s internal piston allows a reduction in damping pressure, for better feedback and smoother action
- The ZX-6R swingarm uses many of the same parts as the ZX-10R; both left and right inner plates, the left outer plate, rear stand bosses, brake caliper stopper, chain guard and swingarm pivot shaft
- Greatly improves braking and initial corner turn-in

Brakes
- New 220mm rear petal disc is 10mm larger
- Revised rear brake lever is now mounted coaxially with the footpeg for increased mid-stroke braking efficiency and improved feeling

Race-quality steering damper
- A race quality adjustable Öhlins steering damper with relief valve and twin-tube design is fitted as standard equipment

Additional Features

- New fairing offers better wind protection and was designed to minimize the effects of cross winds
- Position lamps are now integral with the projector beam headlights; the new Ninja ZX-6R now features dual position lamps like the ZX-10R
- New one-piece fender (previously a three-piece construction) offers improved aerodynamics
- New inner fender above the swingarm helps to reduce turbulence and keep the undertail clean
- Revised front brake hose routing with a three-way joint at the lower triple-clamp facilitates bleeding air from the brake lines
- Similar in design to that of the ZX-10R, the new instrument panel gives at-a-glance information to the rider

Moto Caradisiac Impressions

This time around, Kawasaki seem to be truly serious about hunting down the R6, CBR 600RR, GSX-R600 and even the Daytona 675. The 2009 ZX-6R is indeed an all-new bike – it shares nothing with its predecessor. And to begin with, the new bike looks really good – a perfect mix of aggression and sobriety.

The engine sounds relatively subdued when you start the bike, though the sound is still pleasant. And the riding position and ergonomics feel just right  you immediately feel comfortable on this bike.

On the move, the new engine is docile and smooth at low revs – if you insist, it will even putter along at 2,000rpm, in sixth gear, at 30km/h. But, of course, that’s not what the ZX-6R is meant to do. The bike really comes alive between 8,000-16,000rpm and in that rev range, a handful of throttle instantly translates into hard acceleration and insane speeds. With ram-air, the ZX-6R’s 599cc inline-four makes 134 horsepower at 14,100rpm and, yes, the bike feels very responsive – the throttle twist-grip seems to be directly connected to the rear wheel. And it averages about 17.5km per litre of petrol, which is not too bad.

The new, fully-adjustable big-piston fork (BPF) from Showa is quite a revelation – the Kawasaki’s nose is always absolutely glued to the tarmac and the ride quality is not bad either. And the Nissin bakes, with radial mount callipers at the front, are very powerful – just two fingers on the brake lever are quite enough to bring the bike to a super-quick halt – but you’d better be careful while braking hard in wet weather conditions and/or during an emergency.

The good:
Poise, steering accuracy
Powerful brakes
Riding position
High speed handling
Engine performance

The not-so-good:
Styling too similar to the ZX-10R
Readability of the instruments
Wind protection provided by the fairing is inadequate