Although the ZX-14 looks the same externally, some subtle internal changes result in significant performance advances, with the big Kawasaki getting a boost in overall power while still meeting ever-stricter Euro III emission and noise standards. In fact, one was actually a by-product of the other.
In order to meet the latest Euro III emission standards, a third honeycomb catalyzer was added to the exhaust system, positioned in the collector leading to the twin silencers (where the other two catalyzers are located). Because the collector had to be modified to accept the cata-lyzer, the connecting tubes between the primary headers from cylinders 1-4 and 2-3 were enlarged approximately 75 percent to compensate for the new collector shape. The silencers themselves were redesigned, with the first and third chambers' capacity modified, along with the lengths of the pipes protruding from each baffle plate. Also, the secondary air-injection ports in the cylinder head were made 20 percent larger to handle the increased flow.
In order to increase combustion efficiency, the EFI injector angle in the throttle bodies was increased from 15 to 20 degrees to disperse the atomized fuel over a wider area. The intake ports were subtly massaged for improved flow. The intake and exhaust modifications resulted in a boost in overall torque across the rpm range, especially in the low end.
Reducing mechanical noise was achieved by revising piston profiles and adding a urethane insulation sheet inside the cam chain cover.
Switching to pressure die-casting in the portions of the monocoque chassis' formerly gravity-cast aluminum parts also allowed Kawasaki to shave some weight from the 14.