Editing Anti-lock braking system (section)

===Basic principle===
Wheel speed [[sensor]]s mounted on the front and rear wheel constantly measures the rotational speed of each wheel and delivers this information to an [[Electronic control unit|Electronic Control Unit]] (ECU). The ECU detects two things: 1) if the deceleration of one wheel exceeds a fixed threshold and 2) whether the brake slip, calculated based on information of both wheels, rises above a certain percentage and enters an unstable zone. These are indicators for a high possibility of a locking wheel. To countermeasure these irregularities the ECU signals the hydraulic unit to hold or to release pressure. After signals show the return to the stable zone, the pressure is increased again. Past models used a piston for the control of the [[Fluid pressure#Fluid pressure|fluid pressure]]. Most recent models regulate the pressure by rapidly opening and closing [[solenoid valve]]s.
While the basic principle and [[architecture]] has been carried over from passenger car ABS, typical motorcycle characteristics have to be considered during the development and application processes.
One characteristic is the change of the dynamic wheel load during braking. Compared to cars, the wheel load changes are more drastic, which can lead to a wheel lift up and a fall over. This can be intensified by a soft suspension. Some systems are equipped with a rear-wheel lift-off mitigation functionality. When the indicators of a possible rear lift-off are detected, the system releases brake pressure on the front wheel to counter this behavior.<ref>{{Cite web |url=http://news.consumerreports.org/cars/2012/04/the-most-valuable-motorcycle-feature-antilock-brakes.html |title=The most-valuable motorcycle feature: antilock brakes<!-- Bot generated title --> |access-date=2018-12-03 |archive-url=https://web.archive.org/web/20130615102218/http://news.consumerreports.org/cars/2012/04/the-most-valuable-motorcycle-feature-antilock-brakes.html |archive-date=2013-06-15 }}</ref>
Another difference is that in the case of the motorcycle the front wheel is much more important for stability than the rear wheel. If the front wheel locks up between 0.2-0.7s, it loses gyrostatic forces and the motorcycle starts to oscillate because of the increased influence of side forces operating on the wheel contact line. The motorcycle becomes unstable and falls.