fuel YAMAHA WR 250F 2014 User Guide

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

2-21
CABLE ROUTING DIAGRAM
CABLE ROUTING DIAGRAM
1. Fuel tank breather hose
2. Clamp
3. Diode
4. Hot starter cable
5. Wire harness
6. Hump (frame)
7. Cylinder head breather hose
8. Throttle position sensor lead
9. Neutral switch lead10. Oil hose
11. Clutch cable
12. Starter motor lead
13. Cable guide
14. Negative battery lead
15. AC magneto lead
16. Brake hose
17. Rectifier/regulator lead
18. Carburetor breather hose19. Carburetor overflow hose
20. Catch tank breather hose
21. Hot starter cable protector
22. Rubber cap

2-22
CABLE ROUTING DIAGRAM
A. Insert the end of the fuel tank
breather hose into the hole in
the steering stem.
B. Fasten the throttle cable, hot
starter cable and rectifier/regula-
tor lead onto the frame. Locate
the clamp under the throttle ca-
ble on the right side of the frame,
and face its ends, as well as the
tie ends, downward.
C. Fasten the diode (at the mark-
ing), throttle cable and hot start-
er cable onto the frame. Locate
the clamp end facing toward the
lower right of the frame and with
the tie end facing downward.
D. Fasten the wire harness, throttle
position sensor lead, starter mo-
tor lead and negative battery
lead onto the frame. Pass the
clamp through the hole in the
stay (air cut-off valve). Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
E. Pass the carburetor breather
hoses, carburetor overflow hose
and catch tank breather hose
between the connecting rod and
cross tube (frame).
F. Fasten the neutral switch lead
and oil hose together with the
plastic locking ties and cut off
the tie ends.
G. Fasten the neutral switch lead
and AC magneto lead onto the
frame. Locate the clamp end
facing toward the outside of the
frame and tie end facing toward
the rear of the frame.
H. Pass the clutch cable through
the cable guide.
I. Fasten the starter motor lead,
AC magneto lead and neutral
switch lead onto the frame. Lo-
cate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
J. Fasten the clutch cable, starter
motor lead, negative battery
lead, AC magneto lead and neu-
tral switch lead onto the frame.
Locate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
K. Pass the neutral switch lead and
AC magneto lead on the inside
of the wire harness.
L. Fasten the clutch cable, AC
magneto lead and neutral switch
lead onto the frame. Locate the
clamp end near the clutch cable
and cut off the tie end.M. Pass the clutch cable and wire
harness through the cable
guide.
N. Locate the couplers in the frame
recess.
O. Pass the carburetor breather
hoses, carburetor overflow hose
and catch tank breather hose so
that the hoses do not contact the
rear shock absorber.
P. Secure the coupler by pushing it
into the hole in the headlight
unit.
Q. Fasten the throttle position sen-
sor lead and the hot starter ca-
ble.
R. Locate the clamp between the
hot starter cable protector and
rubber cap.

3-3
MAINTENANCE INTERVALS FOR COMPETITION USE
OIL FILTER
Replace●●
ENGINE GUARD
Replace●Breakage
FRAME
Clean and inspect●●
FUEL TANK, COCK
Clean and inspect●●
BRAKES
Adjust lever position and pedal
height●●
Lubricate pivot point●●
Check brake disc surface●●
Check fluid level and leakage●●
Retighten brake disc bolts, cali-
per bolts, master cylinder bolts
and union bolts●●
Replace pads●
Replace brake fluid●Every one year
FRONT FORKS
Inspect and adjust●●
Replace oil●●Suspension oil "S1"
Replace oil seal●
FRONT FORK OIL SEAL AND
DUST SEAL
Clean and lube●●Lithium base grease
PROTECTOR GUIDE
Replace●
REAR SHOCK ABSORBER
Inspect and adjust●●
Lube●(After
rain
ride)●Molybdenum disulfide grease
Retighten●●
DRIVE CHAIN GUIDE AND
ROLLERS
Inspect●●
SWINGARM
Inspect, lube and retighten●●Molybdenum disulfide grease
RELAY ARM, CONNECTING
ROD
Inspect, lube and retighten●●Molybdenum disulfide grease
SIDESTAND
Lubricate●Lithium base grease ItemAfter
break-
inEvery
race
Every
third
(or 500
km)Every
fifth (or
1,000
km)
As re-
quiredRemarks

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

3-6
ENGINE
ENGINE
REMOVING THE SEAT, FUEL TANK AND SIDE COVERS
Order Part name Q'ty Remarks
Turn the fuel cock to "OFF".
Disconnect the fuel hose.
1Seat 1
2 Air scoop (left and right) 2
3 Bolt (fuel tank) 2
4 Fuel tank 1
5 Left side cover 1 Open the air filter case cover.
6 Right side cover 1 Refer to removal section.
7 Headlight coupler 1
8 Headlight 1

3-8
ENGINE
REMOVING THE EXHAUST PIPE AND SILENCER
Order Part name Q'ty Remarks
Right side coverRefer to "REMOVING THE SEAT, FUEL
TANK AND SIDE COVERS" section.
1 Bolt (silencer clamp) 1 Only loosening.
2 Bolt [silencer (front)] 1
3 Bolt [silencer (rear)] 1
4 Collar 1
5 Silencer 1
6 Silencer clamp 1
7 Nut (exhaust pipe) 2
8 Exhaust pipe 1
9 Gasket 2

3-14
ENGINE
ADJUSTING THE PILOT SCREW
(For EUROPE)
1. Adjust:
• Pilot screw "1"
Adjustment steps:
To optimize the fuel flow at a smaller
throttle opening, each machine's pilot
screw has been individually set at the
factory. Before adjusting the pilot
screw, turn it in fully and count the
number of turns. Record this number
as the factory-set number of turns
out.
a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the
factory-set number of turns.
ADJUSTING THE ENGINE IDLING
SPEED
1. Start the engine and thoroughly
warm it up.
2. Adjust:
• Engine idling speed
Adjustment steps:
a. Turn the throttle stop screw "1"
until the specified engine idling
speed.
Using a digital engine tachometer for
idle speed adjustment, detect the en-
gine idling speed by bringing the
sensing element "c" of the engine ta-
chometer close to the ignition coil "2".
ADJUSTING THE VALVE
CLEARANCE
This section is intended for those who
have basic knowledge and skill con-
cerning the servicing of Yamaha mo-
torcycles (e.g., Yamaha dealers,
service engineers, etc.) Those who
have little knowledge and skill con-
cerning servicing are requested not to
undertake inspection, adjustment,
disassembly, or reassembly only by
reference to this manual. It may lead
to servicing trouble and mechanical
damage.
• The valve clearance should be ad-
justed when the engine is cool to
the touch.
• The piston must be at Top Dead
Center (T.D.C.) on compression
stroke to check or adjust the valve
clearance.
1. Remove:
•Seat
•Fuel tank
Refer to "SEAT, FUEL TANK
AND SIDE COVERS" section.
2. Drain:
• Coolant
Refer to "CHANGING THE
COOLANT" section.
3. Remove:
• Right radiator
Right to "RADIATOR" section in
the CHAPTER 5.
• Carburetor
Refer to "CARBURETOR" section
in the CHAPTER 5.
• Spark plug
• Upper engine bracket
• Cylinder head cover
Refer to "CAMSHAFTS" section
in the CHAPTER 5.4. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
• O-ring
5. Check:
• Valve clearance
Out of specification→Adjust.
Checking steps:
a. Turn the crankshaft counterclock-
wise with a wrench.
b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
In order to be sure that the piston is at
Top Dead Center, the punch mark "c"
on the exhaust camshaft and the
punch mark "d" on the intake cam-
shaft must align with the cylinder
head surface, as shown in the illustra-
tion.
c. Measure the valve clearance "e"
using a feeler gauge "1".
Record the measured reading if the
clearance is incorrect.
Pilot screw (example):
2 turns out
To increase idle speed→Turn the
throttle stop screw "1" in "a".
To decrease idle speed→Turn the
throttle stop screw "1" out "b".
Engine idling speed:
1,750–1,950 r/min
Valve clearance (cold):
Intake valve:
0.10–0.15 mm
(0.0039–0.0059 in)
Exhaust valve:
0.17–0.22 mm
(0.0067–0.0087 in)

3-25
CHASSIS
d. Tighten the steering ring nut "3"
using steering nut wrench "4".
• Apply the lithium soap base grease
on the thread of the steering stem.
• Set the torque wrench to the steer-
ing nut wrench so that they form a
right angle.
e. Loosen the steering ring nut one
turn.
f. Retighten the steering ring nut us-
ing the steering nut wrench.
Avoid over-tightening.
g. Check the steering stem by turn-
ing it lock to lock. If there is any
binding, remove the steering stem
assembly and inspect the steer-
ing bearings.
h. Install the washer "5", collar "6",
upper bracket "7", washer "8",
steering stem nut "9", handlebar
"10", handlebar upper holder "11"
and headlight "12".
• Install the collar "6" with the larger
inside diameter facing downward.
• The handlebar upper holder should
be installed with the punched mark
"a" forward.
• Install the handlebar so that the
marks "b" are in place on both
sides.• Install the handlebar so that the pro-
jection "c" of the handlebar upper
holder is positioned at the mark on
the handlebar as shown.
• Insert the end of the fuel breather
hose "13" into the hole in the steer-
ing stem.
First tighten the bolts on the front
side of the handlebar upper holder,
and then tighten the bolts on the
rear side.
Steering nut wrench:
YU-A9472/90890-01403
Steering ring nut (initial
tightening):
38 Nm (3.8 m•kg, 27
ft•lb)
Steering ring nut (final
tightening):
7 Nm (0.7 m•kg, 5.1
ft•lb)
Steering stem nut:
145 Nm (14.5 m•kg, 105
ft•lb)
Handlebar upper holder:
28 Nm (2.8 m•kg, 20
ft•lb)
Pinch bolt (upper brack-
et):
21 Nm (2.1 m•kg, 15
ft•lb)
Headlight:
7 Nm (0.7 m•kg, 5.1
ft•lb)

3-31
ELECTRICAL
6. Install:
•Battery
• Battery band
7. Connect:
• Battery leads
(to the battery terminals)
First, connect the positive lead "1",
then the negative lead "2".
8. Check:
• Battery terminals
Dirt→Clean with a wire brush.
Loose connection→Connect
properly.
9. Lubricate:
• Battery terminal
10. Install:
• Seat
CHECKING THE FUSE
To avoid a short circuit, always set
the main switch to "OFF" when
checking or replacing a fuse.
1. Remove:
• Seat
• Fuse cover
2. Check:
• Continuity
Checking steps:
a. Remove the fuse "1".
b. Connect the pocket tester to the
fuse and check the continuity.
Set the pocket tester selector to " Ω×
1".
2. Reserve fuse
c. If the pocket tester indicates "∞",
replace the fuse.
3. Replace:
• Blown fuse
Replacement steps:
a. Set the main switch to "OFF".
b. Install a new fuse of the correct
amperage.
c. Set on the switches to verify if the
electrical circuit is operational.
d. If the fuse immediately blows
again, check the electrical circuit.
Never use a fuse with an amperage
rating other than that specified. Im-
provising or using a fuse with the
wrong amperage rating may cause
extensive damage to the electrical
system, cause the starting and ig-
nition systems to malfunction and
could possibly cause a fire.
4. Install:
• Fuse cover
•SeatREPLACING THE HEADLIGHT
BULBS
1. Remove:
• Headlight
Refer to "REMOVING THE SEAT,
FUEL TANK AND SIDE COV-
ERS" section.
2. Remove:
• Headlight bulb holder cover "1"
3. Remove:
• Headlight bulb holder "1"
Remove the headlight bulb holder by
pushing it in and turning it counter-
clockwise.
4. Remove:
• Headlight bulb
Since the headlight bulb gets ex-
tremely hot, keep flammable prod-
ucts and your hands away from the
bulb unit it has cooled down.
5. Install:
• Headlight bulb
Avoid touching the glass part of
the headlight bulb to keep it free
form oil, otherwise the transparen-
cy of the glass, the life of the bulb
and the luminous flux will be ad-
versely affected. If the headlight
bulb gets soiled, thoroughly clean
it with a cloth moistened with alco-
hol or lacquer thinner.
Recommended lubricant:
Lithium soap base
grease
Pocket tester:
YU-03112-C/90890-
03112
Items Amperage
ratingQ'ty
Main fuse 10.0 A 1