The WSBK Champs are not sitting around waiting for anybody to catch up.
The changes to the engine are indicative of the changes to the rest of the bike, in that outwardly it appears largely unchanged, while close examination reveals that very few parts are carried over. All of the changes were aimed at keeping the bombastic power of the 2011 bike, while boosting low to mid-range power to help with acceleration out of corners. With a completely new cylinderhead and crank – that has lost 20% of its weight – Kawasaki claim the new engine’s reduction in inertia allows it to spin-up much faster.
The lighter crank has several other side-effects, too. Not only does it benefit acceleration, but with less sored energy in the crank, it can be decelerated faster, while cornering forces are reducing thanks to the reduction in the gyroscopic effect of the rotating mass.
The new cylinder head’s intake ports are straighter and wider to allow a greater volume of fuel/air mixture to flow more easily into the combustion chamber and to contribute to power production. The exhaust ports are also straighter and wider to allow the chamber to purge more efficiently. Both intake and exhaust ports are also polished to improve gas flow, while the larger diameter intake and exhaust valves are now made from titanium to reduce mass. Larger coolant passageways also help keep the extra heat generated under control.
The engine has revised cam profiles to optimise valve overlap for a strong balance of torque and high-end power, while their chromoly construction further aids the weight reduction. The pistons are shorter and lighter with revised crowns while thicker cylinder walls and a rerouted cooling system have been proven improvements from the firms racing developments. And all of this has been done while still passing the strict Euro4 regulations for noise and emissions.
The airbox is now two litres larger, at 10lires, giving the engine a large volume of air to draw from all helped by a ram-air intake which has been moved further forward for greater efficiency, and an air filter with a larger surface area and higher flow rate. All this conspires to deliver a claimed 207bhp (with ram air) at 13,000rpm, and 84ftlb torque at 11,500rpm.
What else is new?
Exhaust: Shedding weight was a priority, so the new bike uses titanium headers identical in size to the race bike. Kawasaki say this means trackday addicts and racers will only have to replace part of the exhaust to get a fully track-focussed system. There are now three catalysers to help the bike pass stringent Euro4 emissions and noise tests, while the silencer is also now titanium – not stainless steel.
Chassis: The changes to the chassis are not as extensive as those to the engine but the headstock is mounted 7.5mm nearer to the rider, helping to place more weight over the front wheel for improved stability and turn-in. Resonance chambers in the frame help to keep intake noise under control.
Electronics: The new bike gets the latest batch of control systems, all based around the Bosch Inertial Measurement Unit (IMU) which operates through five measured axes plus a calculated programme which allows the bike to know what is going on in terms of lean angle, pitch and yaw, acceleration and braking. Kawasaki have emptied a bucket of acronyms over this bike and that includes: new Sport-Kawasaki TRaction Control (S-KTRC), Kawasaki Launch Control Mode (KLCM), Kawasaki Intelligent anti-lock Brake System (KIBS), Kawasaki Quick Shifter (KQS), Kawasaki Engine Brake Control (KEBC). The bike also has an Ohlins electronic steering damper and a new power mode selection.
Swingarm: Now 15.8mm longer than before, helping to put more weight over the front wheel and improve stability under braking and turn-in.
Suspension: The new front suspension has been jointly developed by the WSB team and Showa, with their Balance Free Front Fork making its mass-production debut on the new ZX-10R. At the rear there’s the firm’s Balance Free Rear Cushion (BFRC) shock. The 43mm fork is said to offer increased ride comfort, braking stability, improved front-end feel, with each leg being independently adjustable for compression and rebound damping. Each leg boasts a separate compressed nitrogen gas canister at the fork bottom with damping force generated separately to the main tube in a different chamber. This allows the whole surface of the main piston to act as a pump, pushing oil towards the valves and keeping pressure more constant.
Brakes: The front calipers are now top-of-the-range Brembo M50 cast aluminium monoblocs, radially-mounted and gripping 330mm twin discs via braided steel hoses. The discs are 200mm wider in diameter than the outgoing bike and they have grooves around the outer edge to increase their surface area and therefore cooling. At the rear a 220mm single disc is gripped by a single piston caliper and also gets steel braided brake lines. At both ends the once fashionable petal discs have succumbed to good old-fashioned round discs.
New aerodynamics: A larger top fairing was requested by the WSB team to help improve high-speed stability and aerodynamic flow. Increased wind protection is claimed to help racers change position more easily under braking turns because the air is less turbulent. The windscreen is now fully supported by the fairing and shouldn’t vibrate as much as the current bike’s at high speed. Intakes at the side of the windscreen reduce negative air pressure in the cockpit to stabilize airflow and reduce helmet buffeting. A new front mudguard gets a stepped design helping to direct air to the radiator to increase cooling.
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