2007 YAMAHA WR 250F engine

MAINTENANCE SPECIFICATIONS
2 - 8
SPEC
Clutch:
Friction plate thickness 2.9 ~ 3.1 mm (0.114 ~ 0.122 in) 2.7 mm
(0.106 in)
Quantity 9 ----
Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ----
Quantity 8 ----
Warp limit ---- 0.1 mm
(0.004 in)
Clutch spring free length 37.0 mm (1.46 in) 36.0 mm
(1.42 in)
Quantity 5 ----
Clutch housing thrust clearance 0.10 ~ 0.35 mm
(0.0039 ~ 0.0138 in)----
Clutch housing radial clearance 0.010 ~ 0.044 mm
(0.0004 ~ 0.0017 in)----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm
(0.002 in)
Kickstarter:
Type Kick and ratchet type ----
Carburetor:
Type/manufacturer FCR-MX37/KEIHIN
I. D. mark 5UME E0
Main jet (M.J) #170
Main air jet (M.A.J) #115
Jet needle (J.N) NJRU
Cutaway (C.A) 1.5
Pilot jet (P.J) #42
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 mm (0.31 in)
Engine idle speed 1,750 ~ 1,950 r/min
Intake vacuum 31.3 ~ 36.7 kPa
(235 ~ 275 mmHg,
9.25 ~ 10.83 inHg)
Hot starter lever free play 3 ~ 6 mm
(0.12 ~ 0.24 in) Item Standard Limit

MAINTENANCE SPECIFICATIONS
2 - 15
SPEC
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Nipple (spoke)—72 3 0.3 2.2
Rear wheel sprocket M8 × 1.25 6 50 5.0 36
Rear brake disc cover M6 × 1.0 2 10 1.0 7.2
Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 19 1.9 13
Engine mounting:
Engine and engine bracket (front) M10 × 1.25 1 53 5.3 38
Engine and frame (lower) M10 × 1.25 1 53 5.3 38
Upper engine bracket and frame M8 × 1.25 4 34 3.4 24
Lower engine bracket and frame M8 × 1.25 4 34 3.4 24
Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
Engine guard M6 × 1.0 3 7 0.7 5.1
Regulator M6 × 1.0 2 7 0.7 5.1
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 70 7.0 50
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame (upper) M8 × 1.25 1 38 3.8 27
Rear frame (lower) M8 × 1.25 2 32 3.2 23
Swingarm and brake hose holder M5 × 0.8 4 2 0.2 1.4
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Upper drive chain tensioner M8 × 1.25 1 16 1.6 11
Lower drive chain tensioner M8 × 1.25 1 16 1.6 11
Drive chain support M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank M6 × 1.0 2 9 0.9 6.5
Fuel cock M6 × 1.0 2 4 0.4 2.9
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Fuel tank bracket and fuel tank M6 × 1.0 4 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 6 7 0.7 5.1
Air scoop and radiator guard (lower) M6 × 1.0 2 6 0.6 4.3
Front fender M6 × 1.0 4 7 0.7 5.1
Rear fender (front) M6 × 1.0 2 7 0.7 5.1
Rear fender (rear) M6 × 1.0 2 11 1.1 8.0
Side cover M6 × 1.0 2 7 0.7 5.1
Seat M8 × 1.25 2 23 2.3 17
Multi-function display bracket and upper
bracketM6 × 1.0 2 7 0.7 5.1
Multi-function display M5 × 0.8 2 4 0.4 2.9
Plate 1 and front fork protector M5 × 0.8 2 4 0.4 2.9
Plate 2 and front fork protector—2 0.5 0.05 0.36

2 - 19
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
SPEC
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm mkg ftlb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg
× m/sec
2 Force
Nm
m  kgNewton meter
Meter kilogramN
× m
m
× kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3 Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed

SPEC
2 - 111
CABLE ROUTING DIAGRAM
1Clamp
2Positive battery lead
3Battery
4Negative battery lead
5Taillight coupler
6CDI unit coupler (6-pin)
7CDI unit coupler (3-pin)
8CDI unit coupler (6-pin)ÈFasten the wire harness, negative battery lead and starter
motor lead to the upper engine bracket (left side). Locate the
clamp end facing toward the upper side of the frame with the
tie end cut off on the inside of the frame.
ÉFasten the wire harness, negative battery lead and starter
motor lead to the upper engine bracket (left side). Locate the
clamp end facing toward the upper side of the frame with the
tie end cut off on the inside of the frame. Clamp the wire har-
ness and negative lead at the marking.
ÊPass the starter motor lead through the hole in the relay
holder.
ËFit the cover securely.
ÌConnect the wire harness to the starter relay.

2 - 115
SPECCABLE ROUTING DIAGRAM
1Throttle cable
2Clamp
3Brake hose
4Clutch cable
5Hose guide
6Main switch coupler
7Wire harness
8Headlight coupler
9Hot starter cable
0Multi-function display bracket
AMain switch
BUpper bracket
CClutch switch coupler
DEngine stop switch coupler
EMulti-function display coupler
FStart switch coupler
GSpeed sensor couplerHSpeed sensor lead
40˚±10˚

2 - 117
SPECCABLE ROUTING DIAGRAM
ÈFasten the start switch lead to the handlebar with the plastic
bands.
ÉFasten the engine stop switch lead and clutch switch lead to
the handlebar with the plastic bands.
ÊPass the brake hose through the hose guides.
ËSecure the coupler by inserting it into the multi-function display
bracket.
ÌPass the throttle cables, clutch cable and hot starter cable
between the upper bracket and multi-function display bracket.
ÍFasten the multi-function display leads to the bracket. Cut off
the tie end.
ÎSecure the coupler by pushing it into the hole in the multi-func-
tion display bracket.
ÏSecure the wire harness clip by pushing it into the hole in the
multi-function display bracket on the inside.
ÐFasten the wire harness to the multi-function display bracket.
Cut off the tie end.ÑFasten the main switch lead (wire harness side) to the multi-
function display bracket. Locate the clamp end facing toward
the lower side of the frame and cut off the tie end.
ÒPass the speed sensor lead through the guide on the outside
of the front fork.
40˚±10˚

3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
NOTE: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 required 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.
ItemAfter
break-inEvery
race
Every third
(or
500 km)Every fifth
(or
1,000 km)As
requiredRemarks
ENGINE OIL
Replace
VALVES
Check the valve clearances The engine must be cold.
Check the valve seats and
valve stems for wear. Inspect
Replace
VALVE SPRINGS
InspectCheck the free length and
the tilt.
Replace
VALVE LIFTERS
InspectCheck for scratches and
wear.
Replace
CAMSHAFTSInspect the camshaft
surface.
Inspect the decompression
system. Inspect
Replace
CAMSHAFT SPROCKETS
InspectCheck for wear on the teeth
and for damage.
Replace
PISTON
InspectInspect crack
Inspect carbon deposits and
eliminate them. Clean
Replace
PISTON RING
InspectCheck ring end gap
Replace
PISTON PIN
Inspect
Replace
CYLINDER HEADInspect carbon deposits and
eliminate them.
Change gasket Inspect and clean
CYLINDER
Inspect and clean Inspect score marks
Inspect wear
Replace
CLUTCH
Inspect and adjust Inspect housing, friction
plate, clutch plate and spring
Replace
TRANSMISSION
Inspect
Replace bearing
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectInspect wear

3 - 16
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, 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 cooling system for leakage.P.3-35 ~ 41
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-49
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-51 ~ 59
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-41 ~ 43
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-43 ~ 45
Brakes Check the play of front brake and effect of front and rear brake. P.3-77 ~ 89
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-91 ~ 95
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-111 ~ 113
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-113 ~ 117
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-97 ~ 109
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.P.3-27 ~ 31
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-89
Lubrication Check for smooth operation. Lubricate if necessary. P.3-119
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-59
Lead connectorsCheck that the AC magneto, CDI unit, and ignition coil are
connected tightly.P.1-9
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 ~ 40