Kawasaki Motorcycle Forums banner

Not open for further replies.
1 - 3 of 3 Posts

534 Posts
Discussion Starter #1

ZX To The Power of Ten: Kawasaki ZX10R Test
by john ivy

Twenty years ago, December 1983, at Laguna Seca Raceway, Kawasaki introduced the first ever Ninja sportbike to the motorcycling world with the debut of the 900 Ninja. On this 20th anniversary, Kawasaki's' Karl Edmondson took the opportunity to announce that Kawasaki has a renewed focus on sportbikes and is making a major effort to re-focus and vitalize Kawasaki sportbikes.

For the World Press Introduction of the Kawasaki 2004 ZX-10R the press was invited to Homestead Speedway outside Miami. With all the major manufacturers putting corporate big guns behind the offerings in the liter bike category, Kawasaki prudently aimed high with their efforts to produce a class leading sportbike.


Kawasaki had specific priorities in the development of the ZX-10R, and the chassis was at the head of the list. With the frame they went over the top, pun intended. With prominent main beams arching over the engine and a unique combination of thin-walled 2.5mm castings and sheet pressings the result gives the ZX-10R a signature all-alloy frame that echoes the ZX-RR MotoGP bike with a minimized distance between the frame neck and the swingarm pivot. This allows the braced swingarm to be made longer, reducing the leverage of the engine on the rear suspension. The swingarm has been engineered for high torsional rigidity and a more flexible lateral rigidity in an acknowledgement of the role of chassis flex as a suspension component when the ZX-10R is leaned over. Resulting wheelbase is listed as 54.5 inches, which is shorter than the ZX-6R by 15mm. The frames' very narrow width in the critical seat and knee areas hint at the tight and tidy 600 class dimensions the ZX-10R achieves.

Up front, triple clamps delivering 102m of trail hold fully adjustable 43mm inverted cartridge forks at a 24 degree rake angle. 16-way adjustments on compression and rebound settings are provided. A black DLC coating on the sliders is designed to provide a smoother action and reduce stiction along with a increased surface hardness. Internally, top out springs are used to stabilize suspension action by reducing weight transfer under hard braking and acceleration. Radial mount 4-pot opposed piston brake calipers handle the braking chores, squeezing semi-floating 300mm petal brake discs. On the other end, the rear shock has step-less adjustments for compression and rebound damping, and spring pre-load adjustment. Rear ride height is adjustable by use of shims. The shock also has top out spring and is connected to aluminum suspension linkage. The rear brake uses a petal type 200mm disk and a tiny single rear caliper that looks smaller than the recent trick Kawasaki race-kit caliper. Kawasaki did not achieve the claimed 175 kilo weight without careful engineering everywhere, and alloy is used for axle spacers and collars, rear suspension bearing arms, bodywork pop nuts and the aluminum forged clip-ons are even gun-drilled.

Significant weight savings were said to be gained with the distinctive new six-spoke wheel design. The key outer rim portion of the wheels weight is reduced and spokes with an "H" cross section are used. Dunlop has developed a new model tire specifically for the ZX-10R, bearing the D218ZR stamping. It is a light weight tire engineered using carbon black particles of a smaller diameter, 16 nanometers compared to a typical 18 nanometers. Dunlop spokesman Mike Manning said this allows the tire to be designed to produce higher grip with less wear.


With the chassis gurus at Kawasaki holding the trump cards, the engine team, lead by Tomohiro Kanazawa, got busy on a totally new, scratch baked 998cc powerplant. They came up with a super-compact 76mm bore 55mm stroke engine with a combined cylinder and upper crankcase assembly, and used a stacked "tri-axis" transmission crankshaft layout and piggybacked the generator behind the clutch. Kawasaki was able to optimize the overall center of gravity on the ZX-10R by using the over-the-engine frame design and ultra-compact motor and the resulting freedom in positioning of the major components.

After being fed air by the wicked central Ram Air duct and swirling through the frame, past a compact air cleaner and flow-analyzed airbox, a reception is waiting in the form of 43mm Mikuni throttle bodies with dual butterfly throttle valves. Fine atomizing injectors squirt a 70 micron mist of fuel into the intake tract. All Kawasaki says is that flow-analysis was used to obtain idealized intake and exhaust port dimensions. After sifting through the tables covered with a dis-assembled ZX-10R powerplant I was pleasantly surprised holding the cylinder head. Very small looking ports for a motor with a claimed 184 horsepower in real top speed conditions, smaller appearance than the ports on the heads of a mid-nineties Muzzy 750cc Superbike head, this I can tell you. The ports all but shout 'high-velocity' and point towards the recent gains made in cylinder head design. 31 mm intake valves opened by billet camshafts with soft-nitrided lobes let the fuel mixture by, then are slammed shut by single valve springs wound from oval section wire held captive by sintered aluminum retainers acting on 4.5mm valve stems, all elements combining to keep the cylinder head compact and lightweight.

Forged 76mm flat top pistons pumping in plated cylinders compress the fuel mixture to a claimed 12.7 to 1 ratio and the mix is ignited by iridium spark plugs and high voltage stick coils. Spent gases exit with a shove through the titanium 25.5mm exhaust valve into the exhaust plumbing. The ZX-10R has a full titanium system, from the head pipes to the tip of the muffler, the pipes and the internals are all titanium. An aluminum covering surrounds the outer surface of the muffler. A butterfly valve in the exhaust is designed to provide a step-less power delivery all through the rpm range. Kawasaki's' KLEEN system uses a honeycomb catalyze fitted inside the muffler to breeze through current environmental emissions standards.

Kawasaki was a pioneer in the development of the Superbike slipper clutch and the ZX-10R sports the latest incarnation which is currently being described as an 'adjustable back torque limiter' but to you and me, it's a slipper clutch. And it is connected to track-ready close-ratio 6-speed transmission with a 17 tooth countershaft sprocket and a 39 tooth sprocket on the rear wheel.


Kawasaki has done a superb job at creating not just a state of the art liter bike with all the key parts in all the right places, but in designing the ZX-10R to be so visually striking and unique in appearance. There has been considerable anticipation surrounding the ZX-10R since early pictures were released. With the signature massive black frame spars arching upwards, the engine sitting low in the frame, a sinister looking Ram-air intake shape and the overall bodywork exuding such an aggressive elegance, the ZX-10R is a real looker in most minds. The speculation immediately shifted to, will it perform as well as its looks suggest?

The frontal area of the ZX-10R is smaller than that of the ZX-6R, which itself has a very tidy nose. The ZX-10R has a neat little set of circular one inch lights inboard of the main and high beam lights and are separately lit, something not really noticeable in the press images. Low beam gets you left side beam illumination. As mentioned earlier, the wheelbase is shorter by 15mm than the ZX-6R, but you would not know this from the riding position. Kawasaki did exhaustive research and testing to come up with the perfect seat/peg/handlebar ergonomics for what they call a naturally aggressive riding position. The tank is concave on the top and very narrow at the rear seat/tank junction. The ZX-10R gives good knee.

A compact electronic dash handles speedometer and tachometer functions, along with temperature, clock, lap timer, trip meter and programmable shift light. The tach, although digital, displays in a circular arc mimicking an analog tachometer and the speed is displayed numerically in miles per hour or kilometers. The ultra-thin tail section is made possible by use of a multi-piece design, remove two sections and the bulk of the ZX-10R electronics are exposed inside. Unlock the pillion seat and there is room for a pair of gloves, cell phone and a few small items but no real storage. The slick looking solo-cowl cover that replaces the pillion seat, it's not included and is sold separately so start twisting your dealer's arm now.

images by tom riles

1 - 3 of 3 Posts
Not open for further replies.