The ABS brakes allow the driver to maintain steering control under heavy braking by preventing a skid and allowing the wheel to maintain traction with the road surface as directed by the rider. The ABS offers improved control on slippery surfaces such as ice, packed snow, gravel, steel plates, wet leaves, wet cement or anything other slippery pavement. The main benefit of ABS on such surfaces is to increase the ability of the driver to maintain control of the vehicle rather than go into a skid. In the four wheel vehicles the ABS is electronically controlled for each wheel. The recent technology allowed the ABS to be controlled none electronically but with the use of sophisticated valve system distributing optimized pressure to the brake master cylinder. In the Motorino scooters the ABS of each disk brake is independent and it is controlled by Hydraulic Control Unit (HCU). The front and the rear wheel units are different considering the fact that approximately 60% of the braking power of two wheel vehicles is provided by the front wheel.

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Anti-lock Brake Systems (ABS) operates as follows:
1. When the brakes are applied, fluid is forced from the brake lever cylinder outlet ports to the HCU inlet ports. This pressure is transmitted through solenoid valves contained inside the HCU to the brake master cylinder of the wheel.
2. The circuit brake master cylinder compresses the brake pads .
3. If the anti-lock brake control module senses a wheel is about to lock, based on anti-lock it closes the normally open solenoid valve for that circuit. This prevents any more fluid from entering that circuit.
4. If that wheel is still decelerating, it opens the solenoid valve for that circuit.
5. Once the affected wheel comes back up to speed, the anti-lock brake control module returns the solenoid valves to their normal condition allowing fluid flow to the affected brake.

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