2015 YAMAHA WR 250F engine

CABLE ROUTING DIAGRAM
2-38
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

CABLE ROUTING DIAGRAM
2-42
1. Clutch switch lead
2. Engine stop switch lead
3. Clutch cable
4. Brake hose guide
5. Headlight lead
6. Speed sensor lead
7. Indicator light coupler
8. Meter assembly optional switch coupler
9. Meter assembly coupler
10. Speed sensor coupler
11. Start switch lead
12. Plastic band
13. Throttle cable
14. Front brake hose
A. Route the throttle cable, clutch cable, clutch
switch lead, engine stop switch lead and start
switch lead between the cable guide of the meter
bracket and handle crown. The cables and leads
may be routed in any order.
B. Clamp the wire harness, clutch switch lead and
start switch lead to the meter bracket. The clamp
shall be located at a position where there is no
slack with the handle turned fully to the left.
C. Connect the headlight lead to the headlight.
D. Clamp the start switch lead to the handlebar by
the plastic band.
E. Clamp the engine stop switch lead and clutch
switch lead to the handlebar by the plastic band.
F. 40°±10°
G. Vertical direction
H. Pass the engine stop switch lead under the han-
dlebar.

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 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 ................................................ 3-13
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 ..................................................... 3-23
CHASSIS........................................................................................................ 3-24
BLEEDING THE BRAKE SYSTEM .......................................................... 3-24
CHECKING THE BRAKE HOSE .............................................................. 3-25
ADJUSTING THE FRONT BRAKE .......................................................... 3-25
ADJUSTING THE REAR BRAKE ............................................................. 3-26
CHECKING THE FRONT BRAKE PADS ................................................. 3-26
CHECKING THE REAR BRAKE PADS ................................................... 3-28
CHECKING THE REAR BRAKE PAD INSULATOR ................................ 3-29
CHECKING THE BRAKE FLUID LEVEL.................................................. 3-29
ADJUSTING THE DRIVE CHAIN SLACK ................................................ 3-30
CHECKING THE FRONT FORK LEGS ................................................... 3-31
CHECKING THE FRONT FORK PROTECTOR GUIDE .......................... 3-31
CLEANING THE FRONT FORK OIL SEAL AND DUST SEAL ................ 3-31
AIR BLEEDING FROM FRONT FORK .................................................... 3-31
ADJUSTING THE FRONT FORK LEGS .................................................. 3-32
CHECKING THE SWINGARM OPERATION ........................................... 3-33
CHECKING THE REAR SUSPENSION ................................................... 3-33

PERIODIC MAINTENANCE
3-1
EAS2GB2076
PERIODIC MAINTENANCE
EAS2GB2077INTRODUCTION
This chapter includes all information necessary to perform recommended checks and adjustments.
If followed, these preventive maintenance procedures will ensure more reliable vehicle operation, a
longer service life and reduce the need for costly overhaul work. This information applies to vehicles
already in service as well as to new vehicles that are being prepared for sale. All service technicians
should be familiar with this entire chapter.
EAS2GB2078PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL SYSTEM
TIP
• From 4200 mi (7000 km) or 9 months, repeat the maintenance intervals starting from 1800 mi (3000
km) or 3 months.
• Items marked with an asterisk should be performed by a Yamaha dealer as they require special
tools, data and technical skills.
NO. ITEM CHECKS AND MAINTENANCE JOBSINITIALODOMETER READ-
INGS
600 mi
(1000
km) or 1
month1800 mi
(3000
km) or 3
months3000 mi
(5000
km) or 6
months
1*Fuel line• Check fuel hoses for cracks or dam-
age.
• Replace if necessary.
2Spark plug• Check condition.
• Adjust gap and clean.
3*Valve clear-
ance• Check and adjust valve clearance
when engine is cold.
4*Air filter ele-
ment• Clean with solvent and apply foam air-
filter oil or equivalent oil.
• Replace if necessary.
5*Breather sys-
tem• Check ventilation hose for cracks or
damage and drain any deposits.
• Replace. Every 2 years
6*Fuel injec-
tion• Adjust engine idling speed.
7Exhaust sys-
tem• Check for leakage.
• Tighten if necessary.
• Replace gasket(s) if necessary.
8Engine oil• Change (warm engine before drain-
ing).
9Engine oil fil-
ter element• Replace.
10Engine oil
strainer• Clean.

PERIODIC MAINTENANCE
3-3
TIP
• The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
• Hydraulic brake service
• After disassembling the brake master cylinders and calipers, always change the fluid. Regularly
check the brake fluid levels and fill the reservoirs as required.
• Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
13
Brake and
clutch lever
pivot shafts• Apply lithium-soap-based grease (all-
purpose grease) lightly.
14Brake pedal
pivot shafts• Apply lithium-soap-based grease (all-
purpose grease) lightly.
15Sidestand
pivot• Check operation.
• Apply lithium-soap-based grease (all-
purpose grease) lightly.
16*Front fork• Check operation and for oil leakage.
• Replace if necessary.
17*Shock ab-
sorber as-
sembly• Check operation and for oil leakage.
• Replace if necessary.
18*Rear suspen-
sion link piv-
ots• Apply molybdenum disulfide grease
lightly.
19*Control ca-
bles• Apply Yamaha chain and cable lube or
engine oil 10W-30 thoroughly.
20*Throttle grip
housing and
cable• Check operation and free play.
• Adjust the throttle cable free play if
necessary.
• Lubricate the throttle grip housing and
cable.
21*Chassis fas-
teners• Check all chassis fitting and fasteners.
• Correct if necessary.
22Battery• Check terminal for looseness and cor-
rosion. NO. ITEM CHECKS AND MAINTENANCE JOBSINITIALODOMETER READ-
INGS
600 mi
(1000
km) or 1
month1800 mi
(3000
km) or 3
months3000 mi
(5000
km) or 6
months

PERIODIC MAINTENANCE
3-4
EAS2GB2080MAINTENANCE INTERVALS FOR COMPETITION USE
TIP
• The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the re-
quired maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
• Periodic inspection is essential in making full use of the machine performance. The service life of
the parts varies substantially according to the environment in which the machine runs (e.g., rain,
dirt, etc.). Therefore, earlier inspection is required by reference to the list below.
ITEMAfter
break-
inEvery
raceEvery
third
(or
500
km)Every
fifth
(or
1,000
km)As re-
quiredRemarks
ENGINE OIL
Replace
VALVES
Check the valve
clearancesThe engine must be cold.
InspectCheck the valve seats and
valve stems for wear.
Replace
VALVE SPRINGS
InspectCheck the free length and the
tilt.
Replace
VALVE LIFTERS
InspectCheck for scratches and wear.
Replace
CAMSHAFTS Inspect the camshaft surface.
InspectInspect the decompression
system.
Replace
CAMSHAFT
SPROCKETS
InspectCheck for wear on the teeth
and for damage.
Replace
PISTON Inspect crack.
InspectInspect carbon deposits and
eliminate them.
Clean
ReplaceIt is recommended that the pis-
ton pin and ring are also re-
placed at the same time.
PISTON RING
InspectCheck ring end gap.
Replace

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 1-32.
AIR FILTER
Clean and lubri-
cateUse foam air-filter oil or equiv-
alent 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

PRE-OPERATION INSPECTION AND MAINTENANCE
3-9
EAS2GB2081
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
EAS2GB2082GENERAL INSPECTION AND MAINTENANCE
TIP
Perform usual maintenance enough so that, in the race course, a confirmation of that and simple set-
ting adjustments may only be left, in order to get enough time to use effectively.ITEM inspect Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.3-10 – 12
FuelCheck that a fresh gasoline is filled in the fuel tank.
Check the fuel line for leakage.1-32
Engine oilCheck that the oil level is correct. Check the crank-
case and oil line for leakage.3-16 – 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and
that the clutch operates smoothly.3-12 – 13
Throttle grip/HousingCheck that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and
housing, if necessary.3-13 – 14
BrakesCheck the play of front brake and effect of front and
rear brake.3-24 – 30
Drive chainCheck drive chain slack and alignment. Check that
the drive chain is lubricated properly.3-30
5-68 – 69
WheelsCheck for excessive wear and tire pressure. Check
for loose spokes and have no excessive play.3-35 – 36
SteeringCheck that the handlebar can be turned smoothly and
have no excessive play.3-36 – 37
Front forks and rear
shock absorberCheck that they operate smoothly and there is no oil
leakage.3-31 – 35
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 pipeCheck that the exhaust pipe is tightly mounted and
has no cracks.3-15 – 16
Rear wheel sprocketCheck that the rear wheel sprocket tightening bolt is
not loose.5-10 – 11
LubricationCheck for smooth operation. Lubricate if necessary. 3-13
3-37 – 38
Bolts and nutsCheck the chassis and engine for loose bolts and
nuts.1-36 – 37
Lead connectorsCheck that the AC magneto, ECU and ignition coil are
connected tightly.1-11 – 14
SettingsIs the machine set suitably for the condition of the rac-
ing course and weather or by taking into account the
results of test runs before racing? Are inspection and
maintenance completely done?4-1 – 8