Z650

Based on feedback from racing activities, the Assist & Slipper Clutch uses two types of cams (an assist cam and a slipper cam) to either drive the clutch hub and operating plate together or apart. Under normal operation, the assist cam functions as a self-servo mechanism, pulling the clutch hub and operating plate together to compress the clutch plates. This allows the total clutch spring load to be reduced, resulting in a lighter clutch lever feel when operating the clutch. When excessive engine braking occurs as a result of quick downshifts (or an accidental downshift) the slipper cam comes into play, forcing the clutch hub and operating plate apart. This relieves pressure on the clutch plates to reduce back-torque and helps prevent the rear tyre from hopping and skidding. This race-style function is particularly useful when sport or track riding.

Late-model sport bikes often use large-bore throttle bodies to generate high levels of power. However, with large diameter throttles, when a rider suddenly opens the throttle, the unrestricted torque response can be strong. Dual throttle valve technology was designed to tame engine response while contributing to performance.
On models with dual throttle valves, there are two throttle valves per cylinder: in addition to the main valves, which are physically linked to the throttle grip and controlled by the rider, a second set of valves, opened and closed by the ECU, precisely regulates intake airflow to ensure a natural, linear response. With the air passing through the throttle bodies becoming smoother, combustion efficiency in improved and power is increased.

KTRC, Kawasaki's advanced traction control system provides both enhanced sport riding performance and the peace of mind to negotiate slippery surfaces with confidence. Multiple rider-selectable modes (the number of modes varies by model) offer progressively greater levels of intrusion to suit the riding situation and rider preference. Less intrusive modes maintain optimum traction during cornering. Designed with sport riding in mind, they facilitate acceleration out of corners by maximising forward drive from the rear wheel. And because Kawasaki’s sophisticated software bases its dynamic analysis on the chassis’ orientation relative to the track surface (rather than relative to a horizontal plane), it is able to take into account corner camber, gradient, etc, and adapt accordingly. In the more intrusive modes (and for some models, in any mode), when excessive wheel spin is detected, engine output is reduced to allow grip to be regained, effectively enabling riders to negotiate both short, slippery patches (train tracks or manhole covers) and extended stretches of bad roads (wet pavement, cobblestone, gravel) with confidence. Models equipped with IMU incorporate chassis-orientation feedback to offer even more precise management.

Using high-precision electronic control for engine management, Kawasaki models can achieve a high level of fuel efficiency. However, fuel consumption is greatly affected by throttle use, gear selection, and other elements under the rider's control. The Economical Riding Indicator is a function that indicates when current riding conditions are consuming a low amount of fuel. The system continuously monitors fuel consumption, regardless of vehicle speed, engine speed, throttle position and other riding conditions. When fuel consumption is low for a given speed (i.e. fuel efficiency is high), an "ECO" mark appears on the instrument panel's LCD screen. By riding so that the "ECO" mark remains on, fuel consumption can be reduced. While effective vehicle speed and engine speed may vary by model, paying attention to conditions that cause the "ECO" mark to appear can help riders improve their fuel efficiency – a handy way to increase cruising range. Further, keeping fuel consumption low also helps minimise negative impact on the environment.

Sudden over-application of the brakes, or braking on low-grip surfaces (surfaces with a low coefficient of friction) such as wet asphalt or manhole covers may cause a motorcycle's wheel(s) to lock up and slip. ABS was developed to prevent such incidents. Kawasaki ABS systems are controlled by high precision and highly reliable programming formulated based on thorough testing of numerous riding situations. By ensuring stable braking performance, they offer rider reassurance that contributes to greater riding enjoyment. And to meet the special requirements of certain riders, specialised ABS systems are also available. For example, KIBS (Kawasaki Intelligent anti-lock Brake System) is a high-precision brake system designed specifically for supersport models, enabling sport riding to be enjoyed by a wider range of riders. And by linking the front and rear brakes, K-ACT (Kawasaki Advanced Coactive-braking Technology) ABS provides the confidence to enjoy touring on heavyweight models. Kawasaki is continually working on the development of other advanced ABS systems.

Compared to Kawasaki's traditional Uni-Trak rear suspension, which mounts the shock unit vertically, with Horizontal Back-link rear suspension, the shock unit is almost horizontal. Kawasaki's original suspension arrangement locates the shock unit very close to the bike's centre of gravity, greatly contributing to mass centralisation. And because there is no linkage or shock unit protruding beneath the swingarm, this frees up space for a larger exhaust pre-chamber (an exhaust expansion chamber situated just upstream of the silencer). With a larger pre-chamber, silencer volume can be reduced, and heavy exhaust components can be concentrated closer to the centre of the bike, further contributing to mass centralisation. The result is greatly improved handling. Another benefit is that the shock unit is placed far away from exhaust heat. Because it is more difficult for heat from the exhaust system to adversely affect suspension oil and gas pressure, suspension performance is more stable. Horizontal Back-link rear suspension offers numerous secondary benefits like this.