Yamaha R1 2004 ServiceManual

7-37
Order Job / Part Q’ty Remarks
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15Removing the injectors
Throttle position sensor coupler
Sub-throttle position sensor coupler
Sub-throttle motor assembly coupler
Intake air pressure sensor coupler
Cylinder #1-injector coupler
Cylinder #2-injector coupler
Cylinder #3-injector coupler
Cylinder #4-injector coupler
Sub wire harness
Negative pressure hose
Intake air pressure sensor
Fuel distributor
Injector
Spring
Thermo wax assembly1
1
1
1
1
1
1
1
1
1
1
1
4
1
1Remove the...

7-38
THROTTLE BODIESFI
Order Job / Part Q’ty Remarks
16
17
18
19
20
21
22
23Idle adjust screw wire
Cotter pin
Washer
Link
Sub-throttle servo motor assembly
Throttle position sensor
Fuel pressure regulator
Throttle body assembly1
2
2
1
1
1
1
1
For installation, reverse the removal
procedure. 

7-39
THROTTLE BODIESFI
CAUTION:
EAS00911
The throttle bodies should not be disas-
sembled.
EAS00912
CHECKING THE INJECTORS
1. Check:

injectors
Damage 
 Replace.
EAS00913
CHECKING THE THROTTLE BODIES
1. Check:

throttle bodies
Cracks / damage 
 Replace the throttle bo-
dies as a set.
2. Check:

fuel passages
Obstructions 
 Clean.
a. Wash the throttle bodies in a petroleum-
based solvent.
Do not use any caustic carburetor cleaning
solution.
b. Blow out all of the passages with com-
pressed air.
EAS00095...

7-40
THROTTLE BODIESFI
NOTE: CHECKING THE PRESSURE REGULATOR
1. Check:

pressure regulator
Damage 
 Replace.
CHECKING THE FUEL PUMP AND
PRESSURE REGULATOR OPERATION
1. Check:

pressure regulator operation
a. Remove the fuel tank.
Refer to “FUEL TANK” in chapter 3.
b. Disconnect the negative pressure hose 
1
from the pressure regulator at the joint.
c. Connect the vacuum / pressure pump gauge
set 
2 onto the negative pressure hose from
the pressure regulator.
d. Connect the pressure gauge 
3 and adapter
4...

7-41
THROTTLE BODIESFI
NOTE:
Increase the vacuum pressure 
 
Fuel pressure is decreased
Decrease the vacuum pressure 
 
Fuel pressure is increased
Faulty 
 Replace the pressure regulator.
EAS00916
CHECKING AND ADJUSTING THE
THROTTLE POSITION SENSOR
Before adjusting the throttle position sensor, the
engine idling speed should be properly ad-
justed.
1. Check:

throttle position sensor
a. Disconnect the throttle position sensor cou-
pler.
b. Remove the throttle position sensor from the
throttle body.
c....

7-42
THROTTLE BODIESFI
NOTE:
Tester positive probe 
 
yellow terminal 
Tester negative probe 

black / blue terminal 
1
2
f. While slowly opening the throttle, check that
the throttle position sensor resistance is with-
in the specified range.
The resistance does not change or it
changes abruptly 
Replace the throttle
position sensor.
The slot is worn or broken 
 Replace the
throttle position sensor.
Check mainly that the resistance changes grad-
ually when turning the throttle, since the read-
ings...

7-43
THROTTLE BODIESFI
NOTE:
CHECKING AND ADJUSTING THE
SUB-THROTTLE POSITION SENSOR
1. Check:

sub-throttle position sensor
a. Disconnect the sub-throttle position sensor
coupler.
b. Remove the sub-throttle position sensor
from the sub-throttle servo motor.
c. Connect the pocket tester (Ω  1k) to the
sub-throttle position sensor.
Positive tester probe 
 blue terminal 
1
Negative tester probe 

black / blue terminal 
2
d. Measure the maximum sub-throttle position
sensor resistance.
Out of specification...

7-44
THROTTLE BODIESFI
2. Adjust:

sub-throttle position sensor full open angle
a. Turn the nut 
1 of the worm shaft of the sub-
throttle counterclockwise until it contacts
with the full open stopper.
b. When the dimension of 
a sections of the
throttle bodies #3 and #4 is measured with a
micrometer caliper, adjust with the adjuster
2 of the output shaft section of the sub-
throttle servo motor so that the dimension is
in a range from 24.2 to 24.6 mm (0.95 to 0.97
in).
AFront side
BRear side
Sub-throttle...

7-45
A
THROTTLE BODIESFI
NOTE:
NOTE:
b. After performing the step a, move the sub-
throttle position sensor to adjust to be in a
range from 0.97 to 1.07 V
Sub-throttle position sensor
voltage
0.97 
 1.07 V
(green / yellow – blue)

After setting up the sub-throttle position sen-
sor, check that the sub-throttle position sensor
output voltage is 0.4 V or more with the nut of
worm shaft turned to the full close side until it
stops.

When the sub-throttle position sensor output
voltage is 0.4 V or more,...

7-46
AIR INDUCTION SYSTEMFI
EAS00507
AIR INDUCTION SYSTEM
AIR INJECTION
The air induction system burns unburned ex-
haust gases by injecting fresh air (secondary
air) into the exhaust port, reducing the emission
of hydrocarbons.
When there is negative pressure at the exhaust
port, the reed valve opens, allowing secondary
air to flow into the exhaust port. The required
temperature for burning the unburned exhaust
gases is approximately 600 to 700C (1112 to
1292F).
EAS0097
AIR CUT-OFF VALVE
The air...