Benelli ZAFFERAN 250, Service Manual

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17.2.3 Throttle Valve
17.2.3.1 General Working Principles:
The throttle valve mainly consists of the main cast valve body, return spring, throttle cable,
throttle position sensor and idle adjustment screw.
The throttle position sensor provides the movement of the throttle to ECU; the idle adjustment
screw is able to control the idle speed and its stability. It reduces the bypass flow clockwise and
lowers the idle speed, while increasing the bypass flow counterclockwise will raise the idle speed.
Normally, it should be fastened by two turns. All above subsystems work together to achieve the
following functions:
● Control the air intake flow
● Control the air flow at idle speed
● Check the throttle position
—provide throttle feedback signals to the engine control system
●
Provides the throttle with return force
17.2.3.2 Appearance