Suzuki GSX-R750, Service Manual

Page: 222 / 495

FI SYSTEM AND INTAKE AIR SYSTEM 4-75
To set the ST valve to fully open position, apply 12 volts to
A
and
B
terminals.
Positive wire –––
B
(Gray wire) terminal
Negative wire –––
A
(Pink wire) terminal
To prevent the motor damage, stop to apply 12V as soon
as the ST valve reaches to fully open position.
Measure the position sensor output voltage at fully open posi-
tion.
Position sensor output voltage
ST valve is fully open: less than 4.8 V
(
+
Yellow –
-
B/Br)
If the measured voltage is more than specification, adjust the No.1
cable adjuster as follows:
• Set the ST valve to adjustment position. (
4-61)
Adjusting the No.1 cable with the ST valve fully opened
can damage the STV actuator. Be sure to adjust the No.2
cable with the ST valve set in adjustment position.
• Turn out the No.1 cable adjuster
1
until the output voltage be-
comes specified value.
Position sensor output voltage
ST valve is fully open: 4.2 output voltage 4.8 V
• Repeat the above procedure until the output voltage is within
the specified value.
• After adjusting the ST control cables, perform 4th step to con-
firm C28 is not indicated.
FUEL INJECTOR INSPECTION
The fuel injector can be checked without removing it from the
throttle body.
Refer to page 4-49 for details.
FUEL INJECTOR REMOVAL
• Lift and support the fuel tank with its prop stay. ( 4-51)
• Remove the air cleaner box. ( 4-61 and -62)
• With battery negative cable disconnected, disconnect the in-
jector couplers.
• Remove the fuel delivery pipe assembly. ( 4-66)
• Remove the fuel injectors No.1, No.2, No.3 and No.4.
( 4-66)
INSPECTION
Check fuel injector filter for evidence of dirt and contamination. If
present, clean and check for presence of dirt in the fuel lines and
fuel tank.
12 V
Gray Gray
Pink Pink