Checking The Fuel Pressure; Installing The Throttle Body Joint - Yamaha YZF-R25 Service Manual

Pressure drops → Check the pressure gauge
and adapter.
Check the seals and O-rings, and then rein-
stall.
Replace the fuel injectors.
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EAS30482

CHECKING THE FUEL PRESSURE

1. Check:
• Fuel pressure
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a. Remove the fuel tank bracket bolts "1" and
holdup the fuel tank.
ECA20070
NOTICE
When lifting up the fuel tank, be careful not
to pull the fuel tank overflow hose and fuel
tank breather hose.
1
b. Disconnect the fuel hose "2" from the throttle
bodies.
EWA16640
WARNING
Cover fuel hose connections with a cloth
when disconnecting them. Residual pres-
sure in the fuel lines could cause fuel to
spurt out when removing the hoses.
ECA20010
NOTICE
Be sure to disconnect the fuel hose by hand.
Do not forcefully disconnect the hose with
tools.
2
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c. Connect the pressure gauge "3" and adapter
"4" to the fuel hose "2".
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3
2
d. Start the engine.
e. Measure the fuel pressure.
1
Faulty → Replace the fuel pump.
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2. Install:
• Fuel tank
Refer to "FUEL TANK" on page 7-1.
EAS30937

INSTALLING THE THROTTLE BODY JOINT

1. Install:
• Throttle body joint "1"
TIP
Align the projection "a" on the throttle body joint
with the slot "b" in the throttle body joint clamp.
7-12
THROTTLE BODIES
Pressure gauge
90890-03153
Pressure gauge
YU-03153
Fuel pressure adapter
90890-03176
Fuel pressure adapter
YM-03176
Fuel line pressure at idling
220–300 kPa (2.2–3.0 kgf/cm²,
31.9–43.5 psi) / Regulated pres-
sure 250 kPa (2.5 kgf/cm², 36.3
psi)
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Rear fuel tank bracket bolt
(frame)
12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Front fuel tank bracket bolt
(frame)
12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Throttle body joint clamp screw
2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
4
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