2017 YAMAHA WR 250F engine coolant

DESCRIPTION
1-4
EAS2GBB009
DESCRIPTION
TIP
Designs and specifications of the vehicle are subject to change without notice. Therefore, please
note that the descriptions in this manual may be different from those for the vehicle you have pur-
chased.1. Clutch lever 12. Headlight
2. Multi-function display 13. Radiator
3. Front brake lever 14. Coolant drain bolt
4. Throttle grip 15. Rear brake pedal
5. Start switch 16. Air filter
6. Radiator cap 17. Drive chain
7. Fuel tank cap 18. Shift pedal
8. Engine stop switch 19. Oil level check window
9. Taillight 20. Starter knob/idle screw
10. Fuel tank 21. Front fork
11. Kickstarter lever
32 1
8
10
91112 1376
54
15 14 21 20 19 18 1716

IMPORTANT INFORMATION
1-7
EAS20180
IMPORTANT INFORMATION
EAS2GBB020PREPARATION FOR REMOVAL AND DIS-
ASSEMBLY
1. Before the jobs, completely remove mud,
dust, and the like in order to prevent the en-
try of them into the inside during the jobs.
• Before cleaning with high-pressure water of
washers, cover the following parts.
Air duct
Silencer exhaust port
Drain hole on the cylinder head (right side)
Hole under the water pump housing
2. Use proper special tools and equipment.
See “SPECIAL TOOLS”.
3. During disassembly, check and measure the
required parts, and make a record of them
so that you may refer to the record when in-
stalling them. Moreover, arrange gears, cyl-
inders, pistons, and other parts for each
section so as not to confuse or lose them.4. During disassembly, clean each of the parts,
and store them in trays for each section.
5. Flammable. Keep servicing areas away
from any source of fire.
6. During servicing, take special care not to re-
ceive an injury or a burn on the engine, the
exhaust pipe, the silencer, or the like.
7. If coolant is left adhered to the chassis, paint
and plating will be damaged. Therefore,
rinse it out with water in good time.
EWA
WARNING
Coolant is potentially harmful and should
be handled with special care.
• If it enters your eyes, wash it away with wa-
ter enough and then get medical attention
• If it splashes on your skin or clothes,
quickly wash it away with water and then
with soapy water.
• If it is swallowed, immediately induce vom-
iting and get medical attention.
EAS2GBB021REPLACEMENT PARTS
Make sure that the parts and grease or oil to be
used for repair of the vehicle, including periodic
replacement parts, are new YAMAHA genuine
parts and recommended parts.
Do not use any used parts, because these may
not be genuine though they have similar ap-
pearances or because the quality may be
changed by aging.

MAINTENANCE AFTER BREAK-IN
1-33
EAS2GBB055
MAINTENANCE AFTER BREAK-IN
After a break-in, perform careful maintenance
to get ready for the next practice or race.
Refer to “PRE-OPERATION INSPECTION
AND MAINTENANCE” on page 3-9.
EAS2GBB056MAJOR MAINTENANCE
1. For the engine
• Leaks around the engine
Check for pressure leaks from the cylinder
head or the cylinder, oil leaks from the
crankcase or the case cover, leaks from the
coolant system, and other leaks.
• Check that the valve, the cylinder head, the
cylinder, the piston, and the piston ring fit
one another, and that contact between the
valve and the cylinder head, and that be-
tween the cylinder and the piston are cor-
rect.
• Engine oil change
Drain the oil, and check for dirt and foreign
materials such as metal chips. (If any foreign
material is mixed, disassemble and check
the crankcase.)
Pour the specified amount of the recom-
mended oil.
• AC magneto
Check for looseness in mounted areas of
the rotor and the stator.
Check that the connector is not being dis-
connected.
• Silencer
Check the main body and stay for cracks.
Check for leaks.
• Mounting bolts and nuts
Check for looseness in mounted areas of
parts, as well as engine mounting bolts and
engine brackets.
2. For the chassis
• Check welds and mounted areas of the
frame, the swingarm, the link, the bracket,
and so on, for looseness and cracks.
• Wheel (s)
Check the wheel for runout. Check the
spoke for looseness.
• Brake(s)
Check the brake disc mounting bolt for
looseness.
Check that the reservoir contains the speci-
fied amount of brake fluid. Check for leaks.• Cable
Grease and adjust cables.
•Drive chain
Lubricate the drive chain and adjust its ten-
sion.
• Fuel tank
Clean the inside of the fuel tank. Check for
leaks.
• Suspension
Check for oil leaks in the front fork or the rear
shock absorber. Check that the mounted
conditions are good.
• Sprocket
Check for looseness in the sprocket mount-
ed on the rear wheel.
• Mounting bolts and nuts
Check mounted areas for looseness.
ECA
NOTICE
After a break-in or before each race, always
check the points shown in “TORQUE-
CHECK POINTS” for tightening torques and
retighten them. (Refer to “TORQUE-CHECK
POINTS” on page 1-34.)
• Greasing and oiling
Always grease or oil the specified points.

ENGINE SPECIFICATIONS
2-6
Throttle body
Type/quantity 30RA-A95R/1
ID mark 2GB1 00
Fuel line pressure (at idle) 300.0–390.0 kPa (3.00–3.90 kgf/cm
2,
43.5–56.6 psi)
Throttle position sensor
Resistance 6.30 k
Output voltage (at idle) 0.48–0.52 V
Fuel injection sensor
Crankshaft position sensor resistance 228–342 
Intake air pressure sensor output voltage 3.61–3.67 V at 101.3 kPa (3.61–3.67 V at
1.01 kgf/cm
2, 3.61–3.67 V at 14.7 psi)
Intake air temperature sensor resistance 5400.0–6600.0  at 0 °C (5400.0–6600.0 
at 32 °F)
289–391  at 80 °C (289–391  at 176 °F)
Coolant temperature sensor resistance 2512–2777  at 20 °C (2512–2777  at 68 °F)
210–220  at 100 °C (210–220  at 212 °F)
Idling condition
Engine idling speed 1900–2100 r/min
CO% 3.0–4.0 % (USA) (CAN)
Intake vacuum 27.3 kPa (205 mmHg, 8.1 inHg) (USA) (CAN)
Water temperature 70–90 °C (158–194 °F)
Oil temperature 70–80 °C (158–176 °F)
Throttle grip free play 3.0–6.0 mm (0.12–0.24 in)

TIGHTENING TORQUES
2-13
EAS2GBB066ENGINE TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEMThread
sizeQ’ty TIGHTENING TORQUES Remarks
Camshaft cap bolt
M6 8 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head blind plug
M12 1 28 Nm (2.8 m·kgf, 20 ft·lbf)
Spark plug
M10 1 13 Nm (1.3 m·kgf, 9.4 ft·lbf)
Cylinder head stud bolt
M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Cylinder head stud bolt (exhaust
pipe)M8 2 15 Nm (1.5 m·kgf, 11 ft·lbf)
Cylinder head bolts
M9 4 33 Nm (3.3 m·kgf, 24 ft·lbf)
Cylinder head nuts
M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head cover bolt
M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pressure check bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer weight plate screw
M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer driven gear nut M14 1 50 Nm (5.0 m·kgf, 36 ft·lbf)
Balancer nut M10 1 38 Nm (3.8 m·kgf, 27 ft·lbf)
Timing chain guide stopper plate
(exhaust side)M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing chain tensioner cap bolt
M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Timing chain tensioner bolt
M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Coolant drain bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator hose clamp screw
M6 8 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Radiator bolt
M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe joint bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator fan bolt
M6 3 8 Nm (0.8 m·kgf, 5.8 ft·lbf)
Water pump housing cover bolt
M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pump bolt
M5 2 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Oil pump cover screw
M4 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Oil strainer bolt
M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Throttle cable cover bolt
M5 1 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Throttle body joint bolt
M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Throttle body joint clamp bolt
M5 1 3.0 Nm (0.30 m·kgf, 2.2 ft·lbf)
Air filter joint clamp bolt
M4 1 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Air filter case bolt M6 3 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Air filter bolt M6 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
E
LT
M
LT
E
LT
LT

CABLE ROUTING DIAGRAM
2-36
1. Cable guide
2. Speed sensor lead
3. Joint coupler
4. Ground lead
5. Throttle position sensor lead
6. Throttle position sensor coupler
7. Radiator breather hose
8. Cylinder head breather hose
9. Crankcase breather hose
10. Radiator hose
11. Fuel hose
12. Engine ground lead
13. Coolant temperature sensor coupler
14. Radiator fan motor lead
15. Intake air pressure sensor coupler
16. Intake air temperature sensor coupler
17. Start switch coupler
18. Radiator fan motor coupler
19. Clutch switch coupler
20. Air filter case
21. Plate
22. Bracket
A. Pass the wire harness under the start switch lead
and clutch switch lead.
B. Insert and fix the joint coupler to the plate. After
fixing it, attach the cover.
C. Pass the throttle position sensor lead to the out-
side of the tension arm (the outside of the vehi-
cle).
D. After connecting the throttle position sensor cou-
pler, attach the cover.
E. Pass the radiator breather hose to the outside of
the tension arm and the throttle position sensor
lead (the outside of the vehicle), and to the inside
of the radiator hose (the side of the vehicle).
F. 45°
G. Install the engine ground lead within a range of
45° from a location where it will not run over the
step difference of the radiator hose joint. Both
sides of the engine ground lead terminal can be
used.
H. Attach the coupler cover to the coolant tempera-
ture sensor coupler.
I. Pass the radiator fan motor lead to the inside of
the tension arm (the side of the vehicle).
J. Install the ground lead terminal between the plate
and the bolt.
K. Fix the ground lead terminal to the detent in the
plate. For the ground lead terminal, either side
will do.
L. Detent

3
PERIODIC CHECKS AND ADJUSTMENTS
PERIODIC MAINTENANCE............................................................................. 3-1
INTRODUCTION ........................................................................................ 3-1
PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL
SYSTEM .................................................................................................... 3-1
GENERAL MAINTENANCE AND LUBRICATION CHART ........................ 3-2
MAINTENANCE INTERVALS FOR COMPETITION USE ......................... 3-4
PRE-OPERATION INSPECTION AND MAINTENANCE................................. 3-9
GENERAL INSPECTION AND MAINTENANCE........................................ 3-9
ENGINE.......................................................................................................... 3-10
CHECKING THE COOLANT LEVEL ........................................................ 3-10
CHECKING THE COOLING SYSTEM ..................................................... 3-10
CHANGING THE COOLANT.................................................................... 3-10
CHECKING THE RADIATOR CAP .......................................................... 3-11
CHECKING THE RADIATOR CAP VALVE OPENING PRESSURE ....... 3-11
CHECKING THE COOLANT CIRCULATORY SYSTEM FOR LEAKS .... 3-12
ADJUSTING THE CLUTCH LEVER FREE PLAY .................................... 3-12
ADJUSTING THE THROTTLE GRIP FREE PLAY .................................. 3-13
LUBRICATING THE THROTTLE CABLE ................................................ 3-14
CLEANING THE AIR FILTER ELEMENT................................................. 3-14
CHECKING THE THROTTLE BODY JOINT ............................................ 3-15
CHECKING THE BREATHER HOSES .................................................... 3-15
CHECKING THE EXHAUST SYSTEM..................................................... 3-15
CHECKING THE FUEL LINE ................................................................... 3-16
CHECKING THE ENGINE OIL LEVEL..................................................... 3-16
CHANGING THE ENGINE OIL ................................................................ 3-17
ADJUSTING THE ENGINE IDLING SPEED ............................................ 3-18
ADJUSTING THE VALVE CLEARANCE ................................................. 3-19
CLEANING THE SPARK ARRESTER ..................................................... 3-24
CHASSIS........................................................................................................ 3-25
BLEEDING THE BRAKE SYSTEM .......................................................... 3-25
CHECKING THE BRAKE HOSE .............................................................. 3-26
ADJUSTING THE FRONT BRAKE .......................................................... 3-26
ADJUSTING THE REAR BRAKE ............................................................. 3-27
CHECKING THE FRONT BRAKE PADS ................................................. 3-27
CHECKING THE REAR BRAKE PADS ................................................... 3-29
CHECKING THE REAR BRAKE PAD INSULATOR ................................ 3-30
CHECKING THE BRAKE FLUID LEVEL.................................................. 3-30
ADJUSTING THE DRIVE CHAIN SLACK ................................................ 3-31
CHECKING THE FRONT FORK LEGS ................................................... 3-32
CHECKING THE FRONT FORK PROTECTOR GUIDE .......................... 3-32
CLEANING THE FRONT FORK OIL SEAL AND DUST SEAL ................ 3-32
AIR BLEEDING FROM FRONT FORK .................................................... 3-32
ADJUSTING THE FRONT FORK LEGS .................................................. 3-33
CHECKING THE SWINGARM OPERATION ........................................... 3-34
CHECKING THE REAR SUSPENSION ................................................... 3-34

PERIODIC MAINTENANCE
3-6
COOLING SYSTEM
Check coolant lev-
el and leakage
Check radiator cap
operation
Replace coolant Every two years
Inspect hoses
OUTSIDE NUTS
AND BOLTS
RetightenRefer to “STARTING AND
BREAK-IN” on page 1-30.
AIR FILTER
Clean and lubri-
cateUse Yamaha foam air filter oil
or other quality foam air filter
oil.
Replace
OIL FILTER
Replace
ENGINE GUARD
Replace Breakage
FRAME
Clean and inspect
FUEL TANK, FUEL
PUMP
Clean and inspect
FUEL HOSE
Inspect
Replace Every four yearsITEMAfter
break-
inEvery
raceEvery
third
(or
500
km)Every
fifth
(or
1,000
km)As re-
quiredRemarks