radiator cap YAMAHA WR 250F 2014 Owners Manual

1-4
DESCRIPTION
DESCRIPTION
• The machine you have purchased may differ slightly from those shown in the following.
• Designs and specifications are subject to change without notice.
1. Clutch lever
2. Hot starter lever
3. Engine stop switch
4. Multi-function display
5. Main switch
6. Start switch
7. Front brake lever
8. Throttle grip
9. Radiator cap
10. Fuel tank cap
11. Taillight
12. Kickstarter lever
13. Fuel tank14. Headlight
15. Radiator
16. Coolant drain bolt
17. Rear brake pedal
18. Valve joint
19. Fuel cock
20. Cold starter knob
21. Air cleaner
22. Catch tank
23. Drive chain
24. Oil level check window
25. Shift pedal
26. Front fork

1-7
SPECIAL TOOLS
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the correct special tool will
help prevent damage caused by the use of improper tools or improvised techniques. The shape and part number used for
the special tool differ by country, so two types are provided. Refer to the list provided to avoid errors when placing an order.
• For U.S.A. and Canada, use part number starting with "YM-", "YU-" or "ACC-".
• For others, use part number starting with "90890-".
Tool name/Part number How to use Illustration
Crankcase separating tool
YU-01135-B, 90890-01135These tool is used to remove the
crankshaft from either case.
Dial gauge and stand
YU-03097-B, 90890-01252
Stand
YU-01256These tools are used to check each
part for runout or bent.
Crankshaft installing tool
Crankshaft installing pot
YU-90058, 90890-01274
Crankshaft installing bolt
YU-90060, 90890-01275
Spacer (crankshaft installer)
YM-91044, 90890-04081
Adapter (M12)
YU-90063, 90890-01278These tools are used to install the
crankshaft.
Piston pin puller set
YU-01304, 90890-01304 This tool is used to remove the pis-
ton pin.
Radiator cap tester
YU-24460-A, 90890-01325
Radiator cap tester adapter
YU-33984, 90890-01352These tools are used for checking
the cooling system.

2-8
MAINTENANCE SPECIFICATIONS
CHASSISCarburetor: ZA, AUS, NZ EUROPE
Type/manufacturer FCR-MX37/KEIHIN←----
I. D. mark 5UME E0 5UML L0 ----
Main jet (M.J) #170 #160 ----
Main air jet (M.A.J) #115←----
Jet needle (J.N) NJRU NNGU ----
Cutaway (C.A) 1.5←----
Pilot jet (P.J) #42 #45 ----
Pilot air jet (P.A.J) #70←----
Pilot outlet (P.O) ø0.9←----
Bypass (B.P) ø1.0←----
Valve seat size (V.S) ø3.8←----
Starter jet (G.S) #68←----
Leak jet (Acc.P) #70←----
Float height (F.H) 8.0 mm (0.31 in)←----
Engine idle speed 1,750–1,950 r/min←----
Intake vacuum 31.0–37.0 kPa
(233–278 mmHg,
9.2–10.9 inHg)←----
Hot starter lever free play 3–6 mm (0.12–0.24
in)←----
Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008
in)
Side clearance 0.090–0.170 mm (0.0035–0.0067 in) 0.24 mm
(0.0094 in)
Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm
(0.0067 in)
Cooling:
Radiator core size
Width 120.2 mm (4.73 in) ----
Height 240.0 mm (9.45 in) ----
Thickness 22.0 mm (0.87 in) ----
Radiator cap opening pressure 95.0–125.0 kPa (0.95–1.25 kg/cm
2, 13.8–
18.1 psi)----
Radiator capacity (total) 0.54 L (0.48 Imp qt, 0.57 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit
Item Standard Limit
Steering system:
Steering bearing typeTaper roller bearing ----

2-12
TIGHTENING TORQUES
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
ItemThread
sizeQ'ty Tightening torque Remarks
Spark plug M10S 1 13 Nm (1.3 m•kg, 9.4 ft•lb)
Camshaft cap M6 10 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head blind plug screw M12 1 28 Nm (2.8 m•kg, 20 ft•lb)
Cylinder head (stud bolt) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Cylinder head (stud bolt) M8 1 15 Nm (1.5 m•kg, 11 ft•lb)
Cylinder head (bolt) M9 4 38 Nm (3.8 m•kg, 27 ft•lb)
Cylinder head (nut) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer weight M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer shaft driven gear M14 1 50 Nm (5.0 m•kg, 36 ft•lb) Lock washer
Timing chain guide (intake side) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner cap bolt M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Impeller M8 1 14 Nm (1.4 m•kg, 10 ft•lb)
Radiator hose clamp M6 10 2 Nm (0.2 m•kg, 1.4 ft•lb)
Coolant drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)Copper
washer
Water pump housing M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator stay M6 6 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator pipe M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil pump cover M4 1 1.7 Nm (0.17 m•kg, 1.2 ft•lb)
Oil pump M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil filter element drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil filter element cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil strainer (crankcase) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil delivery pipe 1 (M10) M10 1 20 Nm (2.0 m•kg, 14 ft•lb)Copper
washer
Oil delivery pipe 1 (M8) M8 2 18 Nm (1.8 m•kg, 13 ft•lb)Copper
washer
△Oil hose M6 3 8 Nm (0.8 m•kg, 5.8 ft•lb)
Oil hose clamp — 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
Oil strainer (oil tank) M6 1 9 Nm (0.9 m•kg, 6.5 ft•lb)
Oil tank drain bolt M8 1 18 Nm (1.8 m•kg, 13 ft•lb)
Oil tank (upper) M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Oil tank and frame M6 3 9 Nm (0.9 m•kg, 6.5 ft•lb)
Oil pressure check bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Carburetor joint M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Carburetor joint clamp M4 2 3 Nm (0.3 m•kg, 2.2 ft•lb)
Air filter joint clamp M6 1 3 Nm (0.3 m•kg, 2.2 ft•lb)

2-15
TIGHTENING TORQUES
△Front brake disc M6 6 12 Nm (1.2 m•kg, 8.7 ft•lb)
△Rear brake disc M6 6 14 Nm (1.4 m•kg, 10 ft•lb)
△Brake pedal M8 1 26 Nm (2.6 m•kg, 19 ft•lb)
△Rear brake master cylinder M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Rear brake master cylinder cap M4 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
△
Rear brake hose union bolt M10 2 30 Nm (3.0 m•kg, 22 ft•lb)Copper
washer
△Rear wheel axle and axle nut M20 1 125 Nm (12.5 m•kg, 90 ft•lb)
△Nipple (spoke) — 72 3 Nm (0.3 m•kg, 2.2 ft•lb)
△Rear wheel sprocket M8 6 50 Nm (5.0 m•kg, 36 ft•lb)
△Rear brake disc cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
△Rear brake caliper protector M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Drive chain puller adjust bolt and locknut M8 2 19 Nm (1.9 m•kg, 13 ft•lb)
Engine mounting:
△Engine and engine bracket (front) M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△Engine and frame (lower) M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△Upper engine bracket and frame M8 4 34 Nm (3.4 m•kg, 24 ft•lb)
△Lower engine bracket and frame M8 4 34 Nm (3.4 m•kg, 24 ft•lb)
△Engine and engine bracket (upper) M10 1 55 Nm (5.5 m•kg, 40 ft•lb)
△Engine guard M6 3 7 Nm (0.7 m•kg, 5.1 ft•lb)
Regulator M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
△Pivot shaft and nut M16 1 85 Nm (8.5 m•kg, 61 ft•lb)
△Relay arm and swingarm M14 1 70 Nm (7.0 m•kg, 50 ft•lb)
△Relay arm and connecting rod M14 1 80 Nm (8.0 m•kg, 58 ft•lb)
△Connecting rod and frame M14 1 80 Nm (8.0 m•kg, 58 ft•lb)
△Rear shock absorber and frame M10 1 56 Nm (5.6 m•kg, 40 ft•lb)
△Rear shock absorber and relay arm M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△Rear frame (upper) M8 1 38 Nm (3.8 m•kg, 27 ft•lb)
△Rear frame (lower) M8 2 32 Nm (3.2 m•kg, 23 ft•lb)
△Swingarm and brake hose holder M54 3 Nm (0.3 m•kg, 2.2 ft•lb)
Swingarm and patch M4 4 2 Nm (0.2 m•kg, 1.4 ft•lb)
Upper drive chain tensioner M8 1 16 Nm (1.6 m•kg, 11 ft•lb)
Lower drive chain tensioner M8 1 16 Nm (1.6 m•kg, 11 ft•lb)
Drive chain support M6 3 7 Nm (0.7 m•kg, 5.1 ft•lb)
Seal guard and swingarm M5 4 6 Nm (0.6 m•kg, 4.3 ft•lb)
△Fuel tank M6 2 9 Nm (0.9 m•kg, 6.5 ft•lb)
△Fuel cock M6 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Seat set bracket and fuel tankM6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Fuel tank bracket and fuel tank M6 4 7 Nm (0.7 m•kg, 5.1 ft•lb)
△Air scoop and fuel tank M6 6 7 Nm (0.7 m•kg, 5.1 ft•lb)
△Air scoop and radiator guard (lower) M6 2 6 Nm (0.6 m•kg, 4.3 ft•lb)
△Front fender M6 4 7 Nm (0.7 m•kg, 5.1 ft•lb)
△Rear fender (front) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
△Rear fender (rear) M6 2 11 Nm (1.1 m•kg, 8.0 ft•lb)ItemThread
sizeQ'ty Tightening torque Remarks

3-2
MAINTENANCE INTERVALS FOR COMPETITION USE
CYLINDER
Inspect and clean●Inspect score marks.
Replace●Inspect wear.
CLUTCH
Inspect and adjust●●Inspect housing, friction plate, clutch
plate and spring.
Replace●
TRANSMISSION
Inspect●
Replace bearing●
SHIFT FORK, SHIFT CAM,
GUIDE BAR
Inspect●Inspect wear.
ROTOR NUT
Retighten●●
MUFFLER
Inspect and retighten●●
Clean●
Replace●
CRANK
Inspect and clean●●
CARBURETOR
Inspect, adjust and clean●●
AIR INDUCTION SYSTEM
Inspect and clean●● ●●
SPARK PLUG
Inspect and clean●●
Replace●
DRIVE CHAIN Use chain lube.
Lubricate, slack, alignment●●Chain slack: 48.0–58.0 mm (1.89–
2.28 in)
Replace●
COOLING SYSTEM
Check coolant level and leakage●●
Check radiator cap operation●
Replace coolant●Every two years
Inspect hoses●
OUTSIDE NUTS AND BOLTS
Retighten●●Refer to "STARTING AND BREAK-
IN" section in the CHAPTER 1.
AIR FILTER
Clean and lubricate●●Use foam air-filter oil or equivalent oil.
Replace● ItemAfter
break-
inEvery
race
Every
third
(or 500
km)Every
fifth (or
1,000
km)
As re-
quiredRemarks
3

3-5
PRE-OPERATION INSPECTION AND MAINTENANCE
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation or practice, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap. Check the cool-
ing system for leakage.P.3-9 – 10
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the fuel
line for leakage.P.1-18
Engine oilCheck that the oil level is correct. Check the crankcase and oil
line for leakage.P.3-12 – 13
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-10 – 11
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-11
Brakes Check the play of front brake and effect of front and rear brake. P.3-17 – 20
Drive chainCheck drive chain slack and alignment. Check that the drive chain
is lubricated properly.P.3-20 – 21
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-24
SteeringCheck that the handlebar can be turned smoothly and have no ex-
cessive play.P.3-24 – 25
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage.
P.3-21 – 24
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down.—
Exhaust pipe Check that the exhaust pipe is tightly mounted and has no cracks. P.3-8 – 9
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-20
Lubrication Check for smooth operation. Lubricate if necessary. P.3-26
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-20
Lead connectorsCheck that the AC magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the course and
weather or by taking into account the results of test runs before
riding? Are inspection and maintenance completely done?P.4-1 – 10

3-9
ENGINE
CHECKING THE SILENCER AND
EXHAUST PIPE
1. Inspect:
• Gasket "1"
Damage→Replace.
INSTALLING THE SILENCER AND
EXHAUST PIPE
1. Install:
• Gasket
• Exhaust pipe "1"
• Nut (exhaust pipe) "2"
First, temporarily install both nuts,
then tighten either of these nuts to 13
Nm (1.3 m•kg, 9.4 ft•lb) and the other
to 20 Nm (2.0 m•kg, 14 ft•lb), and
then come back to the first one and
retighten it to 20 Nm (2.0 m•kg, 14
ft•lb).
2. Install:
• Silencer clamp "1"
• Gasket "2"
• Silencer "3"
• Washer "4"
• Bolt (silencer) "5"CHECKING THE COOLANT LEVEL
Do not remove the radiator cap
"1", drain bolt and hoses when the
engine and radiator are hot. Scald-
ing hot fluid and steam may be
blown out under pressure, which
could cause serious injury. When
the engine has cooled, place a
thick towel over the radiator cap,
slowly rotate the cap counter-
clockwise to the detent. This pro-
cedure allows any residual
pressure to escape. When the
hissing sound has stopped, press
down on the cap while turning
counterclockwise and remove it.
Hard water or salt water is harmful
to the engine parts. You may use
distilled water, if you can't get soft
water.
1. Place the machine on a level
place, and hold it in an upright po-
sition.
2. Remove:
• Radiator cap
3. Check:
• Coolant level "a"
Coolant level low→Add coolant.
1. RadiatorCHANGING THE COOLANT
Do not remove the radiator cap
when the engine is hot.
Take care so that coolant does not
splash on painted surfaces. If it
splashes, wash it away with water.
1. Place a container under the en-
gine.
2. Remove:
• Seat
• Left side cover
3. Remove the catch tank hose from
the catch tank and drain the tank
of its coolant.
4. Remove:
• Coolant drain bolt "1"
5. Remove:
• Radiator cap
Drain the coolant completely.
6. Clean:
• Cooling system
Thoroughly flush the cooling sys-
tem with clean tap water.
7. Install:
• Copper washer
• Coolant drain bolt
8. Fill:
•Radiator
• Engine
To specified level. Nut (exhaust pipe):
20 Nm (2.0 m•kg, 14
ft•lb)
Silencer clamp:
16 Nm (1.6 m•kg, 11
ft•lb)
Bolt (silencer):
30 Nm (3.0 m•kg, 22
ft•lb)
Coolant drain bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Recommended coolant:
High quality ethylene
glycol anti-freeze con-
taining anti-corrosion
for aluminum engine
Coolant "1" and water
(soft water) "2" mixing ra-
tio:
50%/50%
Coolant capacity:
0.99 L (0.87 Imp qt, 1.05
US qt)

3-10
ENGINE
• Do not mix more than one type of
ethylene glycol antifreeze con-
taining corrosion inhibitors for
aluminum engine.
• Do not use water containing im-
purities or oil.
Handling notes of coolant:
The coolant is harmful so it should be
handled with special care.
• When coolant splashes to your
eye.
Thoroughly wash your eye with
water and see your doctor.
• When coolant splashes to your
clothes.
Quickly wash it away with water
and then with soap.
• When coolant is swallowed.
Quickly make him vomit and take
him to a doctor.
9. Install:
• Radiator cap
Start the engine and warm it up
for a several minutes.
10. Check:
• Coolant level
Coolant level low→Add coolant.
CHECKING THE RADIATOR CAP
1. Inspect:
• Seal (radiator cap) "1"
• Valve and valve seat "2"
Crack/damage→Replace.
Exist fur deposits "3" →Clean or
replace.CHECKING THE RADIATOR CAP
OPENING PRESSURE
1. Attach:
• Radiator cap tester "1" and adapt-
er "2"
Apply water on the radiator cap seal.
3. Radiator cap
2. Apply the specified pressure.
3. Inspect:
•Pressure
Impossible to maintain the speci-
fied pressure for 10 seconds→
Replace.
CHECKING THE COOLING
SYSTEM
1. Inspect:
• Coolant level
2. Attach:
• Radiator cap tester "1" and adapt-
er "2"
3. Apply the specified pressure.
• Do not apply pressure more than
specified pressure.
• Radiator should be filled fully.
4. Inspect:
• Pressure
Impossible to maintain the speci-
fied pressure for 10 seconds→
Repair.
•Radiator "1"
• Radiator hose joint "2"
Coolant leakage→Repair or re-
place.
• Radiator hose "3"
Swelling→Replace.
ADJUSTING THE CLUTCH LEVER
FREE PLAY
1. Check:
• Clutch lever free play "a"
Out of specification→Adjust.
2. Adjust:
• Clutch lever free play
Clutch lever free play adjustment
steps:
a. Loosen the locknuts "1".
b. Adjust the free play by changing
their tightening position.
c. Tighten the locknuts.
• Make minute adjustment on the le-
ver side using the adjuster "2".
• After adjustment, check proper op-
eration of clutch lever.
Radiator cap tester:
YU-24460-A/90890-
01325
Radiator cap tester
adapter:
YU-33984/90890-01352
Radiator cap opening
pressure:
95.0–125.0 kPa (0.95–
1.25 kg/cm
2, 13.8–18.1
psi)
Radiator cap tester:
YU-24460-A/90890-
01325
Radiator cap tester
adapter:
YU-33984/90890-01352
Standard pressure:
180 kPa (1.8 kg/cm
2,
25.6 psi)
Clutch lever free play "a"
:
8.0–13.0 mm (0.31–0.51
in)
Locknut:
7 Nm (0.7 m•kg, 5.1
ft•lb)

5-3
RADIATOR
HANDLING NOTE
Do not remove the radiator cap
when the engine and radiator are
hot. Scalding hot fluid and steam
may be blown out under pressure,
which could cause serious injury.
When the engine has cooled, open
the radiator cap by the following
procedure:
Place a thick rag, like a towel, over
the radiator cap, slowly rotate the
cap counterclockwise to the de-
tent. This procedure allows any re-
sidual pressure to escape. When
the hissing sound has stopped,
press down on the cap while turn-
ing counterclockwise and remove
it.
CHECKING THE RADIATOR
1. Inspect:
• Radiator core "1"
Obstruction→Blow out with com-
pressed air through rear of the ra-
diator.
Bent fin→Repair/replace.
INSTALLING THE RADIATOR
1. Install:
• O-ring "1"
• Radiator pipe 1 "2"
• Bolt (radiator pipe) "3"
Apply the lithium soap base grease
on the O-ring.
2. Install:
• Catch tank hose "1"
• Radiator hose 2 "2"
• Radiator hose 3 "3"
• Radiator pipe 2 "4"
• Radiator hose 5 "5"
• Radiator hose 4 "6"
To right radiator "7".
3. Install:
• Right radiator "1"
• Bolt (right radiator) "2"
• Radiator hose 5 "3"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.
4. Install:
• Left radiator "1"
• Bolt (left radiator) "2"
• Radiator hose 1 "3"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.5. Tighten:
• Radiator hose clamp "4"
6. Install:
• Radiator guard "1"
First fit the inner hook portion "a" and
then the outer one "b" onto the radia-
tor.
7. Install:
• Catch tank "1"
• Bolt (catch tank) "2"
• Bolt (catch tank) "3"
• Catch tank hose "4"
• Catch tank breather hose "5"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2. Bolt (radiator pipe):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (right radiator):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (left radiator):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Radiator hose 1:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Radiator hose clamp:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Bolt (catch tank):
7 Nm (0.7 m•kg, 5.1
ft•lb)
Bolt (catch tank):
16 Nm (1.6 m•kg, 11
ft•lb)