Yamaha Wr250r 2008 Manual

 
THROTTLE BODIES 
7-6 
EAS26980 
CHECKING THE INJECTORS
WARNING
 
EWA32D1009  
Replace the fuel injector with a new one if 
you have dropped or impacted it. 
1. Check: 
 
Injectors
Damage  
→ 
 Replace. 
EAS26990 
CHECKING THE THROTTLE BODIES 
1. Check: 
 
Throttle bodies
Cracks/damage  
→ 
 Replace the throttle bod-
ies as a set.
2. Check: 
 
Fuel passages
Obstructions  
→ 
 Clean.

 
a. Wash the throttle bodies in a petroleum-
based solvent.
Do not use any caustic...

 
THROTTLE BODIES 
7-7 
EAS27030 
ADJUSTING THE THROTTLE POSITION 
SENSOR
WARNING
 
EWA32D1011  
Replace the throttle position sensor with a 
new one if you have dropped or impacted it.
NOTE:
 
Before adjusting the throttle position sensor, the 
engine idling speed should be properly adjusted.
1. Check: 
 
Throttle position sensor
Refer to “CHECKING THE THROTTLE PO-
SITION SENSOR” on page 8-79.
2. Adjust: 
 
Throttle position sensor angle

 
a. Connect the throttle...

 
THROTTLE BODIES 
7-8 

 
AIR INDUCTION SYSTEM 
7-9 
EAS27040 
AIR INDUCTION SYSTEM
2
1
3
4 

 
AIR INDUCTION SYSTEM 
7-10 
1. Air filter case
2. Air induction system hose
3. Air cut-off valve
4. Air induction system pipe 

 
AIR INDUCTION SYSTEM 
7-11 
Removing the air cut-off valve assembly 
Order Job/Parts to remove Q’ty Remarks  
Seat Refer to“GENERAL CHASSIS” on page 4-1.
Side cover (left/right)
Air scoop (left/right)
Fuel tank Refer to“FUEL TANK” on page 7-1.
1 Air induction coupler 1 Disconnect.
2 Air induction system pipe 1
3 Gasket 1
4 Pipe3 1
5 Air induction system hose 1
6 Air cut-off valve assembly 1
For installation, reverse the removal proce-
dure.
1
2
3 4
5 6
T R..10 Nm (1.0 m • kg, 7.2 ft • Ib) 
T R..10 Nm...

 
AIR INDUCTION SYSTEM 
7-12 
EAS27060 
CHECKING THE AIR INDUCTION SYSTEM
Air induction 
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, allow-
ing secondary air to flow into the exhaust port.
The required temperature for burning the un-
burned exhaust gases is approximately 600 to
700 
° 
C. 
Air cut-off valve 
The air...

 
AIR INDUCTION SYSTEM 
7-13 
EAS32D12011 
CANISTER (FOR CALIFORNIA) 
Removing the canister 
Order Job/Parts to remove Q’ty Remarks  
1 Canister cover 1
2 Canister 1
3 Hose (fuel tank 
– 
roll over valve) 1
4 Roll over valve 1
5 Hose (roll over valve 
– 
canister) 1
6 Hose (canister 
– 
throttle body) 1
For installation, reverse the removal proce-
dure.
T R..10 Nm (1.0 m • kg, 7.2 ft • Ib) 
1
T R..10 Nm (1.0 m • kg, 7.2 ft • Ib) 
2
56
3
4 

 
1
2
3
4
5
6
7
8
9
 
ELECTRICAL SYSTEM 
IGNITION SYSTEM ........................................................................................8-1  
CIRCUIT DIAGRAM .................................................................................8-1
TROUBLESHOOTING .............................................................................8-3  
ELECTRIC STARTING SYSTEM...................................................................8-5  
CIRCUIT DIAGRAM...

 
CHECKING THE CRANKSHAFT POSITION SENSOR ..........................8-75
CHECKING THE LEAN ANGLE SENSOR ..............................................8-75
CHECKING THE STATOR COIL .............................................................8-76
CHECKING THE RECTIFIER/REGULATOR ...........................................8-76
CHECKING THE HORN...........................................................................8-77
CHECKING THE SPEED SENSOR...