Kawasaki's Smart Ignition System

3-2-1 we have Ignition... Changing the ignition timing is an excellent way of controlling power. The terms 'advance' and 'retard' refer to the timing of the spark relative to the position of the piston in its stroke. The combustion chamber is compressed to its smallest when the crank arm is at the highest point in its arc, called Top Dead Center (TDC).

When the spark fires, it ignites the fuel mixture and causes the bang that makes the power. Ignition advance is when that happens before the piston is at the top of its stroke. Retarding the ignition means that happens later, even with the piston already on its way back down.

Advanced ignition produces more power from less space, whacking the piston down the bore harder. Retarded ignition means the bang follows the piston down the bore. Think of it like swingbal. Advanced ignition is like launching your racquet to meet the approaching ball, and whack it back the other way with maximum force.
Retarded ignition is like hitting the ball in the direction it's already going as it passes you. It's only possible to add a little power to the ball's speed.

Likewise, the engine power will be much softer. Adjusting ignition timing is a highly effective way of changing the result of a given throttle opening.

Kawasaki uses a clever ignition management system to monitor the Kawasaki's ZX-10R engine speed for sudden spikes indicating the tire is slipping. It reacts by retarding the ignition timing to help the tire regain grip. Kawasaki claims the system provides assistance when the rider wants it and not before. This is done by also monitoring throttle position, vehicle speed, and gear position. If an expert rider tries to light up the tires by applying loads of gas, the system will allow it. Near fully-closed or fully-open the system does not act, thereby preventing unwanted interference when at full lean or upright.