1 Operating principle
The Ducati ABS brake system manages the front and rear brake systems separately.
The operating mechanism consists of a pulse generator (phonic wheel), with a ring of slots, fitted onto each wheel.
There are HALL sensors on LH fork leg bottom end and on rear brake calliper holder plate. With vehicle running, they read the slots on the phonic wheel thereby detecting instant wheel speed.
These sensors output data to ABS ECU, which contains a software with a special control algorithm developed by Ducati.
The software compares the vehicle average speed with the instant wheel speed reading and assesses any slipping condition.
If control values are exceeded when the rider commands a certain pressure on brake calliper, the control unit shall hydraulically control the braking system, which is nearly locked up.
The system can modulate pressure at the calliper through a set of solenoid valves which first prevent any further increase of hydraulic pressure (EV valve closing), and then make the pressure decrease (AV valve opening).
The AV valve is opened in a series of pulses (with less than 10 milliseconds between successive pulses), to reduce pressure in steps.
When the wheel begins to turn again in response to the diminished braking force applied and its speed reaches the reference value, the AV release valve will be closed.
Simultaneously, the EV inlet valve is reopened, restoring normal operation of the brake system. The ABS control unit can monitor and modulate brake force in the three following different conditions: dry road surface (high grip), wet or slippery road surface (poor grip) and uneven road surface. ABS functionality is disabled at vehicle speeds lower than 5 km/h.
Please find below a chart explaining ABS operation.
The hydraulic component of the ABS system consists of a primary circuit (from the cylinder to the control unit and from the control unit to the calliper) and a secondary circuit (completely within the control unit). Please find below a chart explaining ABS hydraulic operation.
Key to ABS hydraulic system
 
A
 
Rear brake master cylinder
 
B
 
Front brake master cylinder
 
1A
 
EV rear - Rear calliper inlet valve
 
1B
 
EV front - Front calliper inlet valve
 
2A
 
AV rear - Rear calliper outlet valve
 
2B
 
AV front - Front calliper outlet valve
 
3
 
Brake master cylinder
 
4
 
Accumulators
 
5A
 
Rear calliper
 
5B
 
Left front calliper
 
6B
 
Right front calliper
 
7
 
ABS electronic unit
 
8A
 
Rear speed sensor
 
8B
 
Front speed sensor