2016 YAMAHA WR 250F stop start

ENGINE
3-16
4. Install:
• Exhaust pipe protector
EAS2GB7095CHECKING THE FUEL LINE
1. Remove:
• Seat
• Side cover (left/right)
• Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
• Fuel tank
Refer to “FUEL TANK” on page 8-1.
2. Check:
• Fuel hose “1”
Crack/damage  Replace.
Loose connection  Connect properly.
3. Install:
• Fuel tank
Refer to “FUEL TANK” on page 8-1.
• Air scoop (left/right)
• Seat
• Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
EAS2GB7096CHECKING THE ENGINE OIL LEVEL
1. Stand the vehicle upright on a level surface.
2. Start the engine, warm this up for 3 minutes,
and then stop the engine and wait about 5
minute.
3. Check:
• Oil level
The engine oil level should be between the
minimum level mark “a” and maximum level
mark “b”.
Below the minimum level mark  Add the
recommended engine oil to the proper level.
ECA
NOTICE
• Since engine oil also lubricates the clutch,
the wrong oil types or additives could
cause clutch slippage. Therefore, do not
add any chemical additives.
• Do not allow foreign material to enter the
crankcase. Exhaust pipe protector screw
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
LOCTITE®
4
3
T R..
1
Recommended brand
YAMALUBE
Type
SAE 10W-40, SAE 10W-50, SAE
15W-40, SAE 20W-40 or SAE
20W-50
Recommended engine oil grade
API service SG type or higher,
JASO standard MA
a b

ENGINE
3-17
EAS2GB7097CHANGING THE ENGINE OIL
Stand the vehicle upright on a level surface.
1. Start the engine, warm this up for 3 minutes,
and then stop the engine and wait about 5
minutes.
2. Place an oil pan under the drain bolt.
3. Remove:
• Engine guard “1”
• Oil filler cap “2”
• Drain bolt (with gasket) “3”
4. If the oil filter element is also to be replaced,
perform the following procedure.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the oil filter element cover “1” and
oil filter element “2”.
b. Replace the O-ring “3”.
c. Install the new oil filter element and the oil fil-
ter element cover.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
5. To check the oil strainer, perform the follow-
ing procedure.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the oil strainer “1”.
b. Check the oil strainer.
Damage  Replace.
Clogging due to dirt  Wash with kerosene.
c. Replace the O-ring “2”.
d. Install the oil strainer.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
6. Install:
•Gasket
• Drain bolt
7. Pour the specified amount of engine oil into
the oil filler cap hole.
Oil filter element cover bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
12
3
1
3
2
New
T R..
Oil strainer bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Drain bolt
20 Nm (2.0 m·kgf, 14 ft·lbf)
Engine oil quantity
Without oil filter element replace-
ment
0.83 L (0.88 US qt, 0.73 Imp.qt)
With oil filter element replace-
ment
0.85 L (0.90 US qt, 0.75 Imp.qt)
Quantity (disassembled)
1.10 L (1.16 US qt, 0.97 Imp.qt)
1
2New
T R..
New
T R..

HANDLEBAR
5-33
EAS2GB7193
HANDLEBAR
Removing the handlebar
Order Part name Q’ty Remarks
1 Clutch cable 1 Disconnect.
2 Clutch switch 1
3 Clutch lever holder 1
4 Engine stop switch 1
5 Brake master cylinder 1
6 Throttle cable cap 1
7 Throttle cable (pull) 1 Disconnect.
8 Throttle cable (return) 1 Disconnect.
9 Right grip 1
10 Tube guide 1
11 Start switch 1
12 Left grip 1
13 Handlebar upper holder 2
14 Handlebar 1

CLUTCH......................................................................................................... 6-40
REMOVING THE CLUTCH ...................................................................... 6-43
CHECKING THE FRICTION PLATES...................................................... 6-43
CHECKING THE CLUTCH PLATES ........................................................ 6-43
CHECKING THE CLUTCH SPRINGS...................................................... 6-43
CHECKING THE CLUTCH HOUSING ..................................................... 6-44
CHECKING THE CLUTCH BOSS ............................................................ 6-44
CHECKING THE PRESSURE PLATE ..................................................... 6-44
CHECKING THE PUSH LEVER SHAFT .................................................. 6-44
CHECKING THE CLUTCH PUSH RODS ................................................ 6-44
CHECKING THE PRIMARY DRIVE GEAR .............................................. 6-44
CHECKING THE PRIMARY DRIVEN GEAR ........................................... 6-45
INSTALLING THE OIL SEAL................................................................... 6-45
INSTALLING THE RIGHT CRANKCASE COVER ................................... 6-45
INSTALLING THE CLUTCH ..................................................................... 6-45
INSTALLING THE KICKSTARTER LEVER ............................................. 6-48
KICKSTATER................................................................................................. 6-49
REMOVING THE KICK SHAFT ASSEMBLY ........................................... 6-50
CHECKING THE KICK SHAFT AND RATCHET WHEEL ........................ 6-50
CHECKING THE KICK GEAR, KICK IDLE GEAR AND RATCHET
WHEEL .................................................................................................... 6-50
INSTALLING THE KICK SHAFT ASSEMBLY .......................................... 6-50
INSTALLING THE KICK IDLE GEAR ....................................................... 6-51
SHIFT SHAFT................................................................................................. 6-52
REMOVING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ......... 6-53
REMOVING THE SEGMENT ................................................................... 6-53
CHECKING THE SHIFT SHAFT .............................................................. 6-53
CHECKING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ......... 6-53
CHECKING THE STOPPER LEVER ....................................................... 6-53
INSTALLING THE STOPPER LEVER ..................................................... 6-54
INSTALLING THE SEGMENT.................................................................. 6-54
INSTALLING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY ....... 6-54
INSTALLING THE SHIFT SHAFT ............................................................ 6-55
INSTALLING THE SHIFT PEDAL ............................................................ 6-55
OIL PUMP AND BALANCER GEAR............................................................. 6-56
REMOVING THE BALANCER ................................................................. 6-58
CHECKING THE PRIMARY DRIVE GEAR, BALANCER SHAFT DRIVE
GEAR, AND BALANCER WEIGHT GEAR .............................................. 6-58
CHECKING THE BALANCER .................................................................. 6-58
CHECKING THE OIL PUMP .................................................................... 6-58
ASSEMBLING THE OIL PUMP ................................................................ 6-59
INSTALLING THE OIL PUMP AND BALANCER GEAR .......................... 6-60

CRANKCASE
6-68
EAS2GB7310
CRANKCASE
Separating the crankcase
Order Part name Q’ty Remarks
Engine Refer to “ENGINE REMOVAL” on page 6-1.
PistonRefer to “CYLINDER AND PISTON” on page
6-30.
BalancerRefer to “OIL PUMP AND BALANCER
GEAR” on page 6-56.
Kick shaft assembly Refer to “KICKSTATER” on page 6-49.
Segment Refer to “SHIFT SHAFT” on page 6-52.
Generator rotorRefer to “GENERATOR AND STARTER
CLUTCH” on page 6-62.
1 Timing chain guide (exhaust side) 1
2 Timing chain guide stopper plate 1
3 Timing chain 1
4 Bolt [L = 45 mm (1.77 in)] 7
5 Bolt [L = 60 mm (2.36 in)] 2
6 Bolt [L = 75 mm (2.95 in)] 3
7 Right crankcase 1
8 Left crankcase 1
9 Dowel pin 2
10 Nm (1.0 mkgf, 7.2 ftIbf)T.R
.
12 Nm (1.2 mkgf, 8.7 ftIbf)T.R
.
12 Nm (1.2 mkgf, 8.7 ftIbf)T.R
.
12 Nm (1.2 mkgf, 8.7 ftIbf)T.R
.
3
1 5
2
6410 56
4
4
446
9117
8
9
LT

THROTTLE BODY
8-10
EAS2GB7352CHECKING THE INJECTOR
1. Check:
• Injectors
Obstruction  Replace, and check the fuel
pump and the fuel injection system.
Refer to “FUEL INJECTION SYSTEM” on
page 9-28.
Deposits  Replace.
Damage  Replace.
2. Check:
• Injector resistance
Refer to “CHECKING THE FUEL INJEC-
TOR” on page 9-81.
EAS2GB7353CHECKING THE THROTTLE BODY
1. Check:
• Throttle body
Cracks/damage  Replace.
2. Check:
• Fuel passages
Obstructions  Clean.
ECA
NOTICE
• Before removing the throttle body, clean
the area around the throttle body to pre-
vent dirt and other foreign material from
falling into the engine.
• If the throttle body is subject to strong
shocks or dropped during cleaning, re-
place it.
• Do not use any caustic carburetor clean-
ing solution.
• Do not directly push the throttle valves to
open them.
• Do not loosen the throttle valve stopper
screw “1”, throttle valve pulley nut “2”, or
throttle valve screw “3”. A loss of perfor-
mance may occur.
• Do not use compressed air to clean the
throttle body. Foreign materials may ad-
here to the intake air pressure sensor pas-
sage “a” and fuel injector “b” in the
throttle body.3. Check:
• Starter knob/idle screw passage “c”
Obstruction  Blow out with compressed
air.
EAS2GB7354CHECKING THE THROTTLE BODY JOINT
1. Check:
• Throttle body joint “1”
Crack/damage  Replace.
1 2
3
ba
c
1

IGNITION SYSTEM
9-3
1. Joint connector
2. Joint connector
4. AC magneto
9. Battery
10.Frame ground
11.Starter relay
12.Main fuse
22.ECU (engine control unit)
23.Ignition coil
24.Spark plug
30.Joint connector
35.Lean angle sensor
36.Engine stop switch
48.Frame ground
49.Ignition coil sub-lead

ELECTRIC STARTING SYSTEM
9-7
1. Joint connector
2. Joint connector
3. Joint connector
7. Main relay
9. Battery
10.Frame ground
11.Starter relay
12.Main fuse
13.Starter motor
14.Starter relay diode
22.ECU (engine control unit)
30.Joint connector
36.Engine stop switch
37.Neutral switch
38.Diode
39.Starting circuit cut-off relay
40.Clutch switch
41.Start switch
48.Frame ground