weight YAMAHA YZ250F 2015 Owners Manual

GENERAL SPECIFICATIONS
2-1
EAS1SM5053
GENERAL SPECIFICATIONS
Model
Model 1SM5 (USA) (CAN)
1SM6 (EUR)
1SM7 (JPN)
1SM8 (AUS) (NZL) (ZAF)
Dimensions
Overall length 2165 mm (85.2 in) (USA) (CAN) (AUS) (NZL)
(ZAF)
2170 mm (85.4 in) (EUR) (JPN)
Overall width 825 mm (32.5 in)
Overall height 1280 mm (50.4 in) (USA) (CAN) (EUR) (JPN)
1275 mm (50.2 in) (AUS) (NZL) (ZAF)
Seat height 965 mm (38.0 in) (USA) (CAN) (EUR) (JPN)
960 mm (37.8 in) (AUS) (NZL) (ZAF)
Wheelbase 1475 mm (58.1 in)
Ground clearance 325 mm (12.8 in) (USA) (CAN) (AUS) (NZL)
(ZAF)
330 mm (13.0 in) (EUR) (JPN)
Weight
Curb weight 105 kg (231 lb)

TIGHTENING TORQUES
2-13
EAS1SM5058ENGINE 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)
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)
Air filter guide holder screw
M5 8 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
LT
M
LT
LT
LT

CLUTCH......................................................................................................... 5-35
REMOVING THE CLUTCH ...................................................................... 5-38
CHECKING THE FRICTION PLATES...................................................... 5-38
CHECKING THE CLUTCH PLATES ........................................................ 5-38
CHECKING THE CLUTCH SPRINGS...................................................... 5-38
CHECKING THE CLUTCH HOUSING ..................................................... 5-39
CHECKING THE CLUTCH BOSS ............................................................ 5-39
CHECKING THE PRESSURE PLATE ..................................................... 5-39
CHECKING THE PUSH LEVER SHAFT .................................................. 5-39
CHECKING THE CLUTCH PUSH RODS ................................................ 5-39
CHECKING THE PRIMARY DRIVE GEAR .............................................. 5-39
CHECKING THE PRIMARY DRIVEN GEAR ........................................... 5-40
INSTALLING THE OIL SEAL................................................................... 5-40
INSTALLING THE RIGHT CRANKCASE COVER ................................... 5-40
INSTALLING THE CLUTCH ..................................................................... 5-41
INSTALLING THE KICKSTARTER LEVER ............................................. 5-43
KICKSTATER................................................................................................. 5-44
REMOVING THE KICK SHAFT ASSEMBLY ........................................... 5-45
CHECKING THE KICK SHAFT AND RATCHET WHEEL ........................ 5-45
CHECKING THE KICK GEAR, KICK IDLE GEAR
AND RATCHET WHEEL ......................................................................... 5-45
INSTALLING THE KICK SHAFT ASSEMBLY .......................................... 5-45
INSTALLING THE KICK IDLE GEAR ....................................................... 5-46
SHIFT SHAFT................................................................................................. 5-47
REMOVING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ......... 5-49
REMOVING THE SEGMENT ................................................................... 5-49
CHECKING THE SHIFT SHAFT .............................................................. 5-49
CHECKING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ......... 5-49
CHECKING THE STOPPER LEVER ....................................................... 5-49
INSTALLING THE STOPPER LEVER ..................................................... 5-50
INSTALLING THE SEGMENT.................................................................. 5-50
INSTALLING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ....... 5-50
INSTALLING THE SHIFT SHAFT ............................................................ 5-51
INSTALLING THE SHIFT PEDAL ............................................................ 5-51
OIL PUMP AND BALANCER GEAR............................................................. 5-52
REMOVING THE BALANCER ................................................................. 5-54
CHECKING THE PRIMARY DRIVE GEAR, BALANCER SHAFT
DRIVE GEAR, AND BALANCER WEIGHT GEAR .................................. 5-54
CHECKING THE BALANCER .................................................................. 5-54
CHECKING THE OIL PUMP .................................................................... 5-54
ASSEMBLING THE OIL PUMP ................................................................ 5-55
INSTALLING THE OIL PUMP AND BALANCER GEAR .......................... 5-55

OIL PUMP AND BALANCER GEAR
5-53
Removing the balancer
Order Part name Q’ty Remarks
Primary driven gear Refer to “CLUTCH” on page 5-35.
Right crankcase cover Refer to “CLUTCH” on page 5-35.
Stator Refer to “AC MAGNETO” on page 5-58.
1 Nut (balancer) 1
2 Nut (primary drive gear) 1
3 Nut (balancer shaft driven gear) 1
4 Conical washer 1
5Balancer 1
6 Conical washer 1
7 Primary drive gear 1
8Collar 1
9 Balancer shaft drive gear 1
10 Conical washer 1
11 Balancer weight gear 1
12 Collar 1
For installation, reverse the removal proce-
dure.
T
.R.
75 Nm (7.5 mkgf, 54 ftlbf)T.R.
50 Nm (5.0 mkgf, 36 ftIbf)T
.R.
New
6
12
11
7
8

OIL PUMP AND BALANCER GEAR
5-54
EAS1SM5267REMOVING THE BALANCER
1. Loosen:
• Balancer nut “1”
• Primary drive gear nut “2”
• Balancer weight gear nut “3”
TIP
Place an aluminum plate “a” between the teeth
of the balancer drive gear “4” and balancer
weight gear “5”.
EAS1SM5268CHECKING THE PRIMARY DRIVE GEAR,
BALANCER SHAFT DRIVE GEAR, AND
BALANCER WEIGHT GEAR
1. Check:
• Primary drive gear “1”
• Balancer shaft drive gear “2”
• Balancer weight gear “3”
Wear/damage  Replace.
EAS1SM5269CHECKING THE BALANCER
1. Check:
•Balancer
Crack/damage  Replace.
EAS1SM5270CHECKING THE OIL PUMP
1. Check:
• Oil pump drive gear
• Oil pump driven gear
• Oil pump housing
• Oil pump housing cover
Cracks/damage/wear  Replace the defec-
tive part(s).
2. Measure:
• Inner-rotor-to-outer-rotor-tip clearance “a”
• Outer-rotor-to-oil-pump-housing clearance
“b”
• Oil-pump-housing-to-inner-rotor-and-outer-
rotor clearance “c”
Out of specification  Replace the oil pump.
1
4
a5
2
4a
5
3
Inner-rotor-to-outer-rotor-tip
clearance
Less than
0.150 mm (0.0059 in)
Outer-rotor-to-oil-pump-housing
clearance
0.13–0.18 mm (0.0051–0.0071 in)
Oil-pump-housing-to-inner-and-
outer-rotor
clearance
0.06–0.11 mm (0.0024–0.0043 in)

OIL PUMP AND BALANCER GEAR
5-56
NOTICE
After tightening the bolts, make sure that
the oil pump turns smoothly.
2. Install:
• Collar “1”
• Balancer weight gear “2”
TIP
Install the balancer weight gear and balancer
shaft with their lower splines “a” aligning with
each other.
3. Install:
• Balancer drive gear “1”
• Collar “2”
TIP
• Align the punched mark “a” on the balancer
drive gear with the punched mark “b” on the
balancer weight gear.
• Install the balancer drive gear and crankshaft
with the lower splines “c” aligning with each
other.4. Install:
• Conical washer “1”
• Balancer weight gear nut “2”
• Primary drive gear “3”
• Conical washer “4”
• Primary drive gear nut “5”
•Balancer “6”
• Conical washer “7”
• Balancer nut “8”
TIP
• Apply engine oil to the contact surface and
threaded portion of the primary drive gear nut.
• Place an aluminum plate “a” between the
teeth of the balancer drive gear “9” and bal-
ancer weight gear “10”.
• Install the conical washer with its convex sur-
face “b” outward.
• Align the balancer flat portion “c” with the flat
portion “d”.
21
1
2
Balancer weight gear nut
50 Nm (5.0 m·kgf, 36 ft·lbf)
Primary drive gear nut
75 Nm (7.5 m·kgf, 54 ft·lbf)
Balancer nut
38 Nm (3.8 m·kgf, 27 ft·lbf)
New
T R..
New
T R..
New
T R..
a
210
b
2 91
b53
a41059
3
E