APRILIA DORSODURO 2007, Service Station Manual

Page: 218 / 302

Ride by Wire
RIDE BY WIRE
Operating logic
Those riding motorbikes do not require a specific throttle valve opening from their engines but actually
a specific torque. The Ride by Wire system has been so designed that the throttles of the throttle bodies
are mechanically isolated from the throttle control; their actuation depends exclusively on 2 electrical
motors controlled by the control unit. Therefore, there is a "Throttle map" to which the control unit refers
in order to decide the position at which the throttle valves should be and at what speed they should
reach the pre-set position. The main parameters which influence the throttle map are:
•
Throttle position and opening/closing speed
•
Engine rpm
•
Inlet pressure read at each inlet manifold
•
Rear and front throttle valve position
•
Air temperature
The functions required from the Marelli control unit therefore are:
1. Ride by Wire system control (throttle map)
2. Injection/ignition control
3. System safety checks
1 - Ride by Wire system control
THROTTLE GRIP POSITION SENSOR The throttle grip is the part to which the throttle control cables
arrive; its task is to translate the rider's power request into an electrical signal to be sent to the electronic
control unit. The two throttle cables (opening and closing) actuate on a scroll mounted on a shaft and
which is sent back to its home position by a return spring.
On the shaft covers there are 2 double track potentiometers (4 control tracks) by means of which the
torque demand is read (and checked).
Marelli 5DM electronic control unit Besides the regular control functions of the injection system, it
supervises the throttle bodies: Through the throttle grip position sensor, it reads the torque demand
and, through the THROTTLE MAP, it decides the throttle opening and sends the command to the throttle
valve control unit. It checks the correct operation of each component (Self-diagnosis), of the system
(Safety), and carries out the emergency procedure (Recovery).
EFI throttle control unit The control unit receives the target throttle opening to be carried out and it
actuates on the control acting on the throttle body motors.
It checks (through the throttle position sensor signal) that the throttle bodies have reached the target
position.
It communicates the position reached to the Marelli control unit. It does not actuate on Safety strategies.
Throttle Body The two throttle bodies are made up of:
Power supply
DORSODURO
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