Yamaha FJR13AG Service Manual page 144

Engine idling speed
950–1150 r/min
b. Check the vacuum pressure.
The difference in vacuum pres-
sure between the throttle bodies
should not exceed 1.33 kPa (10
mmHg).
If out of specification → Adjust the throttle
body synchronization.
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Adjusting the throttle body synchronization
1. Remove the fuel tank bolts "1" and lift up the
fuel tank.
ECA23370
NOTICE
When lifting up the fuel tank, be careful not
to pull the fuel tank breather/overflow hose.
2. Adjust:
• Throttle body synchronization
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a. Start the engine, warm it up for several min-
utes, and then let it run at the specified en-
gine idling speed.
Engine idling speed
950–1150 r/min
b. Using the throttle body that has the bypass air
screw "1" with a white paint mark as the stan-
dard, adjust the other throttle bodies by turn-
ing its bypass air screw in or out.
ECA21300
NOTICE
Do not turn the bypass air screw (white paint
mark) of the throttle body that is the stan-
dard. Otherwise, the engine may run roughly
at idle and the throttle bodies may not oper-
ate properly.
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1
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3-9
PERIODIC MAINTENANCE
TIP
• Turn the bypass air screw using the carburetor
angle driver.
• After each step, rev the engine two or three
times, each time for less than a second, and
check the synchronization again.
• If a bypass air screw was removed, turn the
screw in fully and be sure to synchronize the
throttle bodies.
• If the throttle body synchronization can not be
adjusted using the bypass air screw, clean or
replace the throttle bodies.
• The difference in vacuum pressure between
the throttle bodies should not exceed 1.33 kPa
(10 mmHg).
Carburetor angle driver 2
90890-03173
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3. Stop the engine and remove the measuring
equipment.
4. Install:
• Caps
5. Install:
• T–bar
Refer to "GENERAL CHASSIS (6)" on page
4-22.
• Fuel tank
Refer to "FUEL TANK" on page 7-1.
• Rider seat
Refer to "GENERAL CHASSIS (1)" on page
4-1.
6. Adjust:
• Throttle grip free play
Refer to "CHECKING THE THROTTLE GRIP
OPERATION" on page 3-32.
Throttle grip free play
1.0–3.0 mm (0.04–0.12 in)
1
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