2013 YAMAHA YZ250F lock

HOW TO READ DESCRIPTIONS
To help identify parts and clarify pro-
cedure steps, there are exploded dia-
grams at the start of each removal
and disassembly section.
1. An easy-to-see exploded diagram
"1" is provided for removal and
disassembly jobs.2. Numbers "2" are given in the or-
der of the jobs in the exploded di-
agram. A number that is enclosed
by a circle indicates a disassem-
bly step.
3. An explanation of jobs and notes
is presented in an easy-to-read
way by the use of symbol marks
"3". The meanings of the symbol
marks are given on the next page.4. A job instruction chart "4" accom-
panies the exploded diagram,
providing the order of jobs, names
of parts, notes in jobs, etc.
5. For jobs requiring more informa-
tion, the step-by-step format sup-
plements "5" are given in addition
to the exploded diagram and job
instruction chart.
ILLUSTRATED SYMBOLS (Refer to
the illustration)Illustrated symbols "1" to "7" are used
to identify the specifications appear-
ing in the text.
1. With engine mounted
2. Filling fluid
3. Lubricant
4. Special tool
5. Tightening
6. Specified value, Service limit
7. Resistance (Ω), Voltage (V),
Electric current (A)
Illustrated symbols "8" to "13" in the
exploded diagrams indicate grade of
lubricant and location of lubrication
point.
8. Apply engine oil
9. Apply molybdenum disulfide oil
10. Apply brake fluid11. Apply lightweight lithium-soap
base grease
12. Apply molybdenum disulfide
grease
13. Apply silicone grease
Illustrated symbols "14" to "15" in the
exploded diagrams indicate where to
apply a locking agent and where to in-
stall new parts.
14. Apply locking agent (LOC-
TITE
®)
15. Use new one
1
23
45

1-7
CHECKING OF CONNECTION
4. During the machine disassembly,
clean all parts and place them in
trays in the order of disassembly.
This will speed up assembly time
and help assure that all parts are
correctly reinstalled.
5. Keep away from fire.
ALL REPLACEMENT PARTS
1. We recommend to use Yamaha
genuine parts for all replace-
ments. Use oil and/or grease rec-
ommended by Yamaha for
assembly and adjustment.
GASKETS, OIL SEALS AND O-
RINGS
1. All gaskets, oil seals, and O-rings
should be replaced when an en-
gine is overhauled. All gasket sur-
faces, oil seal lips, and O-rings
must be cleaned.
2. Properly oil all mating parts and
bearings during reassembly. Ap-
ply grease to the oil seal lips.
LOCK WASHERS/PLATES AND
COTTER PINS
1. All lock washers/plates "1" and
cotter pins must be replaced
when they are removed. Lock
tab(s) should be bent along the
bolt or nut flat(s) after the bolt or
nut has been properly tightened.BEARINGS AND OIL SEALS
1. Install the bearing(s) "1" and oil
seal(s) "2" with their manufactur-
er's marks or numbers facing out-
ward. (In other words, the
stamped letters must be on the
side exposed to view.) When in-
stalling oil seal(s), apply a light
coating of lightweight lithium base
grease to the seal lip(s). Oil the
bearings liberally when installing.
Do not use compressed air to spin
the bearings dry. This causes dam-
age to the bearing surfaces.
CIRCLIPS
1. All circlips should be inspected
carefully before reassembly. Al-
ways replace piston pin clips after
one use. Replace distorted cir-
clips. When installing a circlip "1",
make sure that the sharp-edged
corner "2" is positioned opposite
to the thrust "3" it receives. See
the sectional view.
CHECKING OF
CONNECTION
Dealing with stains, rust, moisture,
etc. on the connector.
1. Disconnect:
• Connector2. Dry each terminal with an air
blower.
3. Connect and disconnect the con-
nector two or three times.
4. Pull the lead to check that it will
not come off.
5. If the terminal comes off, bend up
the pin "1" and reinsert the termi-
nal into the connector.
6. Connect:
• Connector
The two connectors "click" together.
7. Check for continuity with a tester.
• If there in no continuity, clean the
terminals.
• Be sure to perform the steps 1 to 7
listed above when checking the
wire harness.
• For a field remedy, use a contact re-
vitalizer available on the market.
• Use the tester on the connector as
shown.

1-16
CLEANING AND STORAGE
CLEANING AND STORAGE
CLEANING
Frequent cleaning of your machine
will enhance its appearance, maintain
good overall performance, and ex-
tend the life of many components.
1. Before washing the machine,
block off the end of the exhaust
pipe to prevent water from enter-
ing. A plastic bag secured with a
rubber band may be used for this
purpose.
2. If the engine is excessively
greasy, apply some degreaser to
it with a paint brush. Do not apply
degreaser to the chain, sprockets,
or wheel axles.
3. Rinse the dirt and degreaser off
with a garden hose; use only
enough pressure to do the job.
Do not use high-pressure washers
or steam-jet cleaners since they
cause water seepage and deterio-
ration seals.
4. After the majority of the dirt has
been hosed off, wash all surfaces
with warm water and a mild deter-
gent. Use an old toothbrush to
clean hard-to-reach places.
5. Rinse the machine off immediate-
ly with clean water, and dry all
surfaces with a soft towel or cloth.
6. Immediately after washing, re-
move excess water from the
chain with a paper towel and lubri-
cate the chain to prevent rust.
7. Clean the seat with a vinyl uphol-
stery cleaner to keep the cover
pliable and glossy.
8. Automotive wax may be applied
to all painted or chromed surfac-
es. Avoid combination cleaner-
waxes, as they may contain abra-
sives.
9. After completing the above, start
the engine and allow it to idle for
several minutes.STORAGE
If your machine is to be stored for 60
days or more, some preventive mea-
sures must be taken to avoid deterio-
ration. After cleaning the machine
thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines, and
the carburetor float bowl.
2. Remove the spark plug, pour a ta-
blespoon of SAE 10W-40 motor
oil in the spark plug hole, and re-
install the plug. With the engine
stop switch pushed in, kick the en-
gine over several times to coat the
cylinder walls with oil.
3. Remove the drive chain, clean it
thoroughly with solvent, and lubri-
cate it. Reinstall the chain or store
it in a plastic bag tied to the frame.
4. Lubricate all control cables.
5. Block the frame up to raise the
wheels off the ground.
6. Tie a plastic bag over the exhaust
pipe outlet to prevent moisture
from entering.
7. If the machine is to be stored in a
humid or salt-air environment,
coat all exposed metal surfaces
with a film of light oil. Do not apply
oil to rubber parts or the seat cov-
er.
Make any necessary repairs before
the machine is stored.

2-5
MAINTENANCE SPECIFICATIONS
Stem runout limit ---- 0.01 mm
(0.0004 in)
Valve seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
Valve seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
Valve spring:
Free length (IN) 39.76 mm (1.57 in) 38.76 mm (1.53
in)
Free length (EX) 37.78 mm (1.49 in) 36.78 mm (1.45
in)
Set length (valve closed) (IN) 28.98 mm (1.14 in) ----
Set length (valve closed) (EX) 28.30 mm (1.11 in) ----
Compressed force (installed) (IN) 99–114 N at 28.98 mm (9.9–11.4 kg at
28.98 mm, 22.27–25.57 lb at 1.14 in)----
Compressed force (installed) (EX) 126–145 N at 28.30 mm (12.6–14.5 kg at
28.30 mm, 28.44–31.97 lb at 1.11 in)----
Tilt limit* (IN) ---- 2.5°/1.7 mm
(2.5°/0.067 in)
Tilt limit* (EX) ---- 2.5°/1.6 mm
(2.5°/0.063 in)
Direction of winding (top view) (IN) Clockwise ----
Direction of winding (top view) (EX) Clockwise ----
Piston:
Piston to cylinder clearance 0.030–0.055 mm (0.0012–0.0022 in) 0.1 mm (0.004
in)
Piston size "D" 76.955–76.970 mm (3.0297–3.0303 in) ----
Measuring point "H" 9 mm (0.35 in) ----
Piston off-set 0 mm (0 in) ----Item Standard Limit

2-10
TIGHTENING TORQUES
ELECTRICAL
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufacturer 17D-51/YAMAHA ----
Charging coil 1 resistance (color) 720–1,080 Ωat 20 °C (68 °F) (Green–
Brown)----
Charging coil 2 resistance (color) 44–66 Ωat 20 °C (68 °F) (Black–Pink) ----
Pickup coil resistance (color) 248–372 Ωat 20 °C (68 °F) (White–Red) ----
CDI unit-model/manufacturer 17D-90/YAMAHA ----
Ignition coil:
Model/manufacturer 5UL-20/DENSO ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.08–0.10 Ωat 20 °C (68 °F) ----
Secondary coil resistance 4.56–6.84 kΩat 20 °C (68 °F) ----
ItemThread
sizeQ'ty Tightening torque Remarks
Spark plug M10S 1 13 Nm (1.3 m•kg, 9.4 ft•lb)
Camshaft cap M6 10 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head blind plug screw M12 1 28 Nm (2.8 m•kg, 20 ft•lb)
Cylinder head (stud bolt) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Cylinder head (stud bolt) M8 1 15 Nm (1.5 m•kg, 11 ft•lb)
Cylinder head (bolt) M9 4 38 Nm (3.8 m•kg, 27 ft•lb)
Cylinder head (nut) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer weight M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer shaft driven gear M14 1 50 Nm (5.0 m•kg, 36 ft•lb) Lock washer
Timing chain guide (intake side) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner cap bolt M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Impeller M8 1 14 Nm (1.4 m•kg, 10 ft•lb)
Radiator hose clamp M6 10 2 Nm (0.2 m•kg, 1.4 ft•lb)
Coolant drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)Copper
washer
Water pump housing M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator M6 6 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator pipe M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil pump cover M4 1 1.7 Nm (0.17 m•kg, 1.2 ft•lb)
Oil pump M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil filter element drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)

2-11
TIGHTENING TORQUES
Oil filter element cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil strainer (crankcase) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil delivery pipe 1 (M10) M10 1 20 Nm (2.0 m•kg, 14 ft•lb)Copper
washer
Oil delivery pipe 1 (M8) M8 2 18 Nm (1.8 m•kg, 13 ft•lb)Copper
washer
△Oil hose M6 3 8 Nm (0.8 m•kg, 5.8 ft•lb)
Oil hose clamp — 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Oil strainer (oil tank) M6 1 9 Nm (0.9 m•kg, 6.5 ft•lb)
Oil tank drain bolt M8 1 18 Nm (1.8 m•kg, 13 ft•lb)
Oil tank (upper) M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Oil tank and frame M6 3 9 Nm (0.9 m•kg, 6.5 ft•lb)
Carburetor joint clamp M5 1 3 Nm (0.3 m•kg, 2.2 ft•lb)
Air filter joint clamp M6 1 3 Nm (0.3 m•kg, 2.2 ft•lb)
Throttle cable (pull) M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Throttle cable (return) M12 1 11 Nm (1.1 m•kg, 8.0 ft•lb)
Throttle cable cover M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Hot starter plunger M12 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Hot starter cable adjust bolt and locknut M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
△Air filter case M6 2 8 Nm (0.8 m•kg, 5.8 ft•lb)
Air filter joint and air filter case M5 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Air filter element M6 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Exhaust pipe M8 2 20 Nm (2.0 m•kg, 14 ft•lb)
△Exhaust pipe protector M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
△Silencer M8 2 30 Nm (3.0 m•kg, 22 ft•lb)
Silencer clamp M8 1 14 Nm (1.4 m•kg, 10 ft•lb)
Crankcase M6 11 12 Nm (1.2 m•kg, 8.7 ft•lb)
Crankcase bearing stopper M6 11 10 Nm (1.0 m•kg, 7.2 ft•lb)
Crankcase bearing stopper (crankshaft) M6 4 14 Nm (1.4 m•kg, 10 ft•lb) Stake.
Left crankcase cover M6 8 10 Nm (1.0 m•kg, 7.2 ft•lb)
Right crankcase cover M6 8 10 Nm (1.0 m•kg, 7.2 ft•lb)
Clutch cover M6 7 10 Nm (1.0 m•kg, 7.2 ft•lb)
Crankcase oil drain bolt M10 1 20 Nm (2.0 m•kg, 14 ft•lb)Copper
washer
△Crankshaft end accessing screw M32 1 —
△Timing mark accessing screw M14 1 —
△Drive chain sprocket cover M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Kick shaft ratchet wheel guide M6 2 12 Nm (1.2 m•kg, 8.7 ft•lb) Lock washer
Kickstarter crank M8 1 33 Nm (3.3 m•kg, 24 ft•lb)
Primary drive gear M18 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Clutch spring M6 5 10 Nm (1.0 m•kg, 7.2 ft•lb)
Clutch boss M16 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Clutch cable locknut M8 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Clutch cable adjust bolt and locknutM6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Push lever shaft M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb) ItemThread
sizeQ'ty Tightening torque Remarks

2-12
TIGHTENING TORQUES
CHASSIS
△- marked portion shall be checked for torque tightening after break-in or before each race.
Drive sprocket M18 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Drive axle oil seal stopper M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Segment M8 1 30 Nm (3.0 m•kg, 22 ft•lb)
Shift guide M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Stopper lever M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Shift pedal M6 1 12 Nm (1.2 m•kg, 8.7 ft•lb)ItemThread
sizeQ'ty Tightening torque Remarks
ItemThread
sizeQ'ty Tightening torque Remarks
△Upper bracket and outer tube M84 21 Nm (2.1 m•kg, 15 ft•lb)
△Lower bracket and outer tube M8 4 21 Nm (2.1 m•kg, 15 ft•lb)
△Upper bracket and steering stem M24 1 145 Nm (14.5 m•kg, 105 ft•lb)
△Handlebar upper holder and handlebar
lower holderM8 4 28 Nm (2.8 m•kg, 20 ft•lb)
△Handlebar lower holder and upper brack-
etM10 2 34 Nm (3.4 m•kg, 25 ft•lb)
△Steering stem and steering ring nut M28 1 Refer to TIP.
Front fork and damper assembly M51 2 30 Nm (3.0 m•kg, 22 ft•lb)
Front fork and adjuster M22 2 55 Nm (5.5 m•kg, 40 ft•lb)Copper
washer
Damper assembly and base valve M42 2 29 Nm (2.9 m•kg, 21 ft•lb)
Adjuster and damper assembly M12 2 29 Nm (2.9 m•kg, 21 ft•lb)
Front fork bleed screw and base valve M5 2 1 Nm (0.1 m•kg, 0.7 ft•lb)
△Front fork and front fork protector M6 6 5 Nm (0.5 m•kg, 3.6 ft•lb)
△Lower bracket and brake hose guide M6 1 9 Nm (0.9 m•kg, 6.5 ft•lb)
△Front fork protector and brake hose hold-
erM6 2 8 Nm (0.8 m•kg, 5.8 ft•lb)
Throttle grip cap M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
△Front brake master cylinder M6 29 Nm (0.9 m•kg, 6.5 ft•lb)
Brake lever mounting bolt M6 1 6 Nm (0.6 m•kg, 4.3 ft•lb)
Brake lever mounting nut M6 1 6 Nm (0.6 m•kg, 4.3 ft•lb)
Brake lever position locknut M6 1 5 Nm (0.5 m•kg, 3.6 ft•lb)
Clutch lever holder M6 2 5 Nm (0.5 m•kg, 3.6 ft•lb)
Clutch lever mounting nut M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Clutch lever position lock nut M5 1 5 Nm (0.5 m•kg, 3.6 ft•lb)
Hot starter lever holder M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Hot starter lever mounting nut M5 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Front brake master cylinder cap M4 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
△
Front brake hose union bolt M10 2 30 Nm (3.0 m•kg, 22 ft•lb)Copper
washer
△Front brake caliper M8 2 28 Nm (2.8 m•kg, 20 ft•lb)
Pad pin plug M10 2 3 Nm (0.3 m•kg, 2.2 ft•lb)

2-13
TIGHTENING TORQUES
△Front brake caliper and pad pin M10 1 18 Nm (1.8 m•kg, 13 ft•lb)
△Rear brake caliper and pad pin M10 1 18 Nm (1.8 m•kg, 13 ft•lb)
△Brake caliper and bleed screw M8 2 6 Nm (0.6 m•kg, 4.3 ft•lb)
△Front wheel axle and axle nut M16 1 105 Nm (10.5 m•kg, 75 ft•lb)
△Front wheel axle holder M8 4 21 Nm (2.1 m•kg, 15 ft•lb)
△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)
△
Footrest bracket and frame M10 4 55 Nm (5.5 m•kg, 40 ft•lb)TORX
△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 M22 1 135 Nm (13.5 m•kg, 98 ft•lb)
△Nipple (spoke) — 72 3 Nm (0.3 m•kg, 2.2 ft•lb)
△Rear wheel sprocket M8 6 42 Nm (4.2 m•kg, 30 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 21 Nm (2.1 m•kg, 15 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, 25 ft•lb)
△Front engine bracket and frame M8 4 34 Nm (3.4 m•kg, 25 ft•lb)
△Engine and engine bracket (upper) M10 2 55 Nm (5.5 m•kg, 40 ft•lb)
Lower engine guard M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
CDI unit bracket M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Cable guide and frame 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 2 32 Nm (3.2 m•kg, 23 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)
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 1 9 Nm (0.9 m•kg, 6.5 ft•lb)
△Fuel cock M6 2 4 Nm (0.4 m•kg, 2.9 ft•lb)ItemThread
sizeQ'ty Tightening torque Remarks