Weber Injection-Ignition System (I.a.w. 15M); Description Of The System; Fuel Circuit; Sucked Air Circuit - MOTO GUZZI Quota 1100 ES Owner's Manual

MOTO GUZZI • Quota 1100 ES • Owner's Manual
WEBER injection-
ignition system
(I.A.W. 15M)
In the Weber injection-ignition system type "alfa/N" the engine speed and the throttle
position are used to measure the quantity of sucked air; when the quantity of air is known,
measure the fuel quantity in relation with the desired strength. Other sensors in the system
allow to adjust the main operation, on particular condition. Moreover, the engine speed and
the throttle angle allow to calculate the optimal ignition advance on every operation
condition. The quantity of air sucked from each cylinder per cycle, depends on the air
density in the suction manifold, on the single displacement and on the volume efficiency.
The volume efficiency is experimentally calculated on the whole operation field of the motor
(rpm and engine load) and is stored in the electronic unit. The control of the injectors, each
cylinder, is "time sequenced", i.e. the two injectors are controlled on the basis of the suction
sequence, while the delivery can already begin, for each cylinder, from the expansion phase
until the suction phase, already begun. The timing for the initial delivery is contained in the
electronic unit.
Static inductive-discharge ignition with dwell control provided by the power module (in-built
in the electronic box) and ignition advance mapping stored in the electronic box. The coils
receive the control inputs from the I.A.W. 15M unit (that calculates the ignition advance) via
the power modules.

Description of the system

Fuel circuit

The fuel is injected along the suction pipe of every cylinder, in the upper side of the suction
valve.
It includes: tank, pump, filter, pressure adjuster, electroinjectors.

Sucked air circuit

The circuit includes: air filter, suction pipe, floated casing.
Downstream the throttle valve is installed the plug for the pressure adjuster.
The potentiometer for the throttle position is assembled on the throttle shaft.
The max pressure sensor (built into the unit) and the air temperature sensor are installed
upstream from the throttle valve.

Control circuit

With this circuit, the electronic unit detects the engine conditions and the performance of
the fuel exhaust and the ignition advance.
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