1-11
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.
Frame construction Frame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear For link type Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Installation of rear shock absorber Rear shock absorber to frame
Installation of swingarm Tightening of pivot shaft
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle
Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp
2-1
GENERAL SPECIFICATIONS
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name: YZ250FY (USA, CDN, AUS, NZ)
YZ250F (EUROPE, ZA)
Model code number: 5XCR (USA,CDN)
5XCS (EUROPE)
5XCU (AUS, NZ, ZA)
Dimensions: USA, CDN EUROPE AUS, NZ, ZA
Overall length 2,163 mm (85.16
in)2,172 mm (85.51
in)2,170 mm (85.43
in)
Overall width 825 mm (32.48 in)←←
Overall height 1,299 mm (51.14
in)1,300 mm (51.18
in)←
Seat height 984 mm (38.74 in) 997 mm (39.25 in) 985 mm (38.78 in)
Wheelbase 1,469 mm (57.83
in)1,476 mm (58.11
in)←
Minimum ground clearance 370 mm (14.57 in) 372 mm (14.65 in) 371 mm (14.61 in)
Dry weight:
Without oil and fuel 92.7 kg (204 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3 (8.76 Imp oz, 8.42 US oz)
Bore × stroke 77.0 × 53.6 mm (3.03 × 2.11 in)
Compression ratio 13.5 : 1
Starting system Kickstarter
Lubrication system: Dry sump
Oil type or grade:
Engine oil (For USA and CDN)
Yamalube 4, SAE10W-40 or SAE20W-50
Yamalube 4-R, SAE10W-50
API service SG type or higher,
JASO standard MA
(Except for USA and CDN)
SAE10W-30, SAE10W-40, SAE15W-40,
SAE20W-40 or SAE20W-50
API service SG type or higher,
JASO standard MA
Oil capacity:
Engine oil
Periodic oil change 1.05 L (0.92 Imp qt, 1.11 US qt)
With oil filter replacement 1.15 L (1.01 Imp qt, 1.22 US qt)
Total amount 1.30 L (1.14 Imp qt, 1.37 US qt)
2
2-6
MAINTENANCE SPECIFICATIONS
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" 8 mm (0.31 in) ----
Piston off-set 0.5 mm (0.020 in)/IN-side ----
Piston pin bore inside diameter 16.002–16.013 mm (0.6300–0.6304 in) 16.043 mm
(0.6316 in)
Piston pin outside diameter 15.991–16.000 mm (0.6296–0.6299 in) 15.971 mm
(0.6288 in)
Piston rings:
Top ring:
Type Barrel ----
Dimensions (B × T) 0.90 × 2.75 mm (0.04 × 0.11 in) ----
End gap (installed) 0.15–0.25 mm (0.006–0.010 in) 0.50 mm (0.020
in)
Side clearance (installed) 0.030–0.065 mm (0.0012–0.0026 in) 0.12 mm (0.005
in)
2nd ring:
Type Taper ----
Dimensions (B × T) 0.80 × 2.75 mm (0.03 × 0.11 in) ----
End gap (installed) 0.30–0.45 mm (0.012–0.018 in) 0.80 mm (0.031
in)
Side clearance 0.020–0.055 mm (0.0008–0.0022 in) 0.12 mm (0.005
in)
Oil ring:
Dimensions (B × T) 1.50 × 2.25 mm (0.06 × 0.09 in) ----
End gap (installed) 0.10–0.40 mm (0.004–0.016 in) ----
Crankshaft:
Crank width "A" 55.95–56.00 mm (2.203–2.205 in) ----
Runout limit "C" 0.03 mm (0.0012 in) 0.05 mm (0.002
in)
Big end side clearance "D" 0.15–0.45 mm (0.0059–0.0177 in) 0.50 mm (0.02
in) Item Standard Limit
2-8
MAINTENANCE SPECIFICATIONS
CHASSISIntake vacuum 29.3–34.7 kPa
(220–260 mmHg,
8.66–9.45 inHg)←----
Hot starter lever free play 3–6 mm (0.12–0.24
in)←----
Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008
in)
Side clearance 0.09–0.17 mm (0.0035–0.0067 in) 0.24 mm (0.009
in)
Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm
(0.0067 in)
Cooling:
Radiator core size
Width 120.2 mm (4.7 in) ----
Height 240 mm (9.4 in) ----
Thickness 22 mm (0.9 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2, 15.6 psi) ----
Radiator capacity (total) 0.58 L (0.51 Imp qt, 0.61 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN EUROPE, AUS, NZ, ZA
Front fork travel 300 mm (11.8 in)←----
Fork spring free length 454 mm (17.9 in)←449 mm (17.7
in)
Spring rate, STD K = 4.4 N/mm (0.449 kg/
mm, 25.1 lb/in)K = 4.5 N/mm (0.459 kg/
mm, 25.7 lb/in)----
Optional spring Yes←----
Oil capacity 521 cm
3 (18.3 lmp oz,
17.6 US oz)←----
Oil grade Suspension oil "S1"←----
Inner tube outer diameter 48 mm (1.89 in)←----
Front fork top end 5 mm (0.20 in)←----
Rear suspension: USA, CDN EUROPE, AUS, NZ, ZA
Shock absorber travel 131.5 mm (5.18 in)←----
Spring free length 260 mm (10.24 in)←----
Fitting length 251 mm (9.88 in) 248 mm (9.76 in)
Preload length
in)←----
2-10
TIGHTENING TORQUES
ELECTRICAL
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
Clutch lever free play (lever end) 7–12 mm (0.28–0.47 in) ----
Throttle grip free play 3–5 mm (0.12–0.20 in) ----Item Standard Limit
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufacturer 5XC-10/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 5XC-R0/YAMAHA (For USA and CDN) ----
5XC-S0/YAMAHA (Except for USA and
CDN)----
Ignition coil:
Model/manufacturer 5UL-10/DENSO ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.08–0.10 Ωat 20 °C (68 °F) ----
Secondary coil resistance 4.6–6.8 kΩat 20 °C (68 °F) ----
Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb
Spark plug M10S × 1.0 1 13 1.3 9.4
Camshaft cap M6 × 1.0 10 10 1.0 7.2
Cylinder head blind plug screw M12 × 1.0 1 28 2.8 20
Cylinder head (stud bolt) M6 × 1.0 2 7 0.7 5.1
Cylinder head (stud bolt) M8 × 1.25 1 15 1.5 11
Cylinder head (bolt) M9 × 1.25 4 38 3.8 27
Cylinder head (nut) M6 × 1.0 2 10 1.0 7.2
Cylinder head cover M6 × 1.0 2 10 1.0 7.2
Cylinder M6 × 1.0 1 10 1.0 7.2
Balancer weight M6 × 1.0 2 10 1.0 7.2
Balancer shaft driven gear M14 × 1.0 1 50 5.0 36
Timing chain guide (intake side) M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner cap bolt M6 × 1.0 1 7 0.7 5.1
Impeller M8 × 1.25 1 14 1.4 10
Radiator hose clamp M6 × 1.0 10 2 0.2 1.4
Coolant drain bolt M6 × 1.0 1 10 1.0 7.2
Water pump housing M6 × 1.0 4 10 1.0 7.2
Radiator M6 × 1.0 6 10 1.0 7.2
3-6
ENGINE
ENGINE
CHECKING THE COOLANT LEVEL
Do not remove the radiator cap
"1", drain bolt and hoses when the
engine and radiator are hot. Scald-
ing hot fluid and steam may be
blown out under pressure, which
could cause serious injury. When
the engine has cooled, place a
thick towel over the radiator cap,
slowly rotate the cap counter-
clockwise to the detent. This pro-
cedure allows any residual
pressure to escape. When the
hissing sound has stopped, press
down on the cap while turning
counterclockwise and remove it.
Hard water or salt water is harmful
to the engine parts. You may use
distilled water, if you can't get soft
water.
1. Place the machine on a level
place, and hold it in an upright po-
sition.
2. Remove:
• Radiator cap
3. Check:
• Coolant level "a"
Coolant level low→Add coolant.
1. Radiator
CHANGING THE COOLANT
Do not remove the radiator cap
when the engine is hot.
Take care so that coolant does not
splash on painted surfaces. If it
splashes, wash it away with water.
1. Place a container under the en-
gine.
2. Remove:
• Coolant drain bolt "1"
3. Remove:
•Radiator cap
Drain the coolant completely.
4. Clean:
• Cooling system
Thoroughly flush the cooling sys-
tem with clean tap water.
5. Install:
• Copper washer
• Coolant drain bolt
6. Fill:
•Radiator
•Engine
To specified level.
• Do not mix more than one type of
ethylene glycol antifreeze con-
taining corrosion inhibitors for
aluminum engine.
• Do not use water containing im-
purities or oil.
Handling notes of coolant:
The coolant is harmful so it should be
handled with special care.
• When coolant splashes to your
eye.
Thoroughly wash your eye with
water and see your doctor.
• When coolant splashes to your
clothes.
Quickly wash it away with water
and then with soap.
• When coolant is swallowed.
Quickly make him vomit and take
him to a doctor.
7. Install:
•Radiator cap
Start the engine and warm it up
for a several minutes.
8. Check:
• Coolant level
Coolant level low→Add coolant.
CHECKING THE RADIATOR CAP
1. Inspect:
• Seal (radiator cap) "1"
• Valve and valve seat "2"
Crack/damage→Replace.
Exist fur deposits "3" →Clean or
replace.
CHECKING THE RADIATOR CAP
OPENING PRESSURE
1. Attach:
• Radiator cap tester "1" and adapt-
er "2"
Apply water on the radiator cap seal.
Coolant drain bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Recommended coolant:
High quality ethylene
glycol anti-freeze con-
taining anti-corrosion
for aluminum engine
Coolant "1" and water
(soft water) "2" mixing ra-
tio:
50%/50%
Coolant capacity:
0.99 L (0.87 Imp qt, 1.05
US qt)
Radiator cap tester:
YU-24460-01/90890-
01325
Radiator cap tester
adapter:
YU-33984/90890-01352
3-9
ENGINE
7. Install:
• Air filter element "1"
• Washer
• Fitting bolt
Align the projection "a" on filter guide
with the hole "b" in air filter case.
CHECKING THE ENGINE OIL
LEVEL
1. Start the engine, warm it up for
several minutes, and then turn off
the engine and wait for five min-
utes.
2. Place the machine on a level
place and hold it up on upright po-
sition by placing the suitable
stand under the engine.
3. Inspect:
• Oil level
Oil should be up to the full level in
the check window "1".
Level check window is not full. →
Add 0.2 L (0.18 Imp qt, 0.21 US
qt) of oil.
• Engine oil also lubricates the
clutch and the wrong oil types or
additives could cause clutch
slippage. Therefore, do not add
any chemical additives or use en-
gine oils with a grade of CD "a"
or higher and do not use oils la-
beled "ENERGY CONSERVING
II" "b"• Do not allow foreign materials to
enter the crankcase.
(For USA and CDN)
(Except for USA and CDN)
4. Install:
• Oil tank cap
5. Start the engine and let it warm up
for several minutes.
6. Turn off the engine and inspect
the oil level once again.
Wait a few minutes until the oil settles
before inspecting the oil level.
CHANGING THE ENGINE OIL
1. Start the engine and warm it up
for several minutes, and then turn
off the engine and wait for five
minute.
2. Place the machine on a level place and hold it on upright posi-
tion by placing the suitable stand
under the engine.
3. Place a suitable container under
the engine.
4. Remove:
• Lower engine guard "1"
• Bolt (oil tank) "2"
• Washer "3"
• Oil filler cap "4"
• Oil tank drain bolt "5"
• Crankcase oil drain bolt "6"
• Oil filter element drain bolt "7"
Drain the crankcase and oil tank
of its oil.
5. Remove:
• Oil hose clamp "1"
• Bolt (oil hose)
•Oil hose "2"
• Oil strainer "3"
6. Inspect:
• Oil strainer
Clogged→Blow.
7. If the oil filter is to be replaced dur-
ing this oil change, remove the fol-
lowing parts and reinstall them. Fitting bolt:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Recommended oil:
Yamalube 4, SAE10W-
40 or SAE20W-50
Yamalube 4-R,
SAE10W-50
API service SG type or
higher, JASO standard
MA
Recommended oil:
SAE10W-30, SAE10W-
40, SAE15W-40,
SAE20W-40 or
SAE20W-50
API service SG type or
higher, JASO standard
MA
4
5-14
FRONT BRAKE AND REAR BRAKE
4. Install:
• Copper washer "1"
•Brake hose "2"
• Union bolt "3"
Always use new copper washers.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake master cylinder.
INSTALLING THE REAR BRAKE
HOSE
1. Install:
• Copper washer "1"
•Brake hose "2"
• Union bolt "3"
Always use new copper washers.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.
2. Install:
• Brake hose holder "1"
• Screw (brake hose holder) "2"
After installing the brake hose
holders, make sure the brake hose
does not contact the spring (rear
shock absorber). If it does, correct
its twist.
FILLING THE BRAKE FLUID
1. Fill:
•Brake fluid
Until the fluid level reaches
"LOWER" level line "a".
ŒUse only the designated quality
brake fluid:
otherwise, the rubber seals may
deteriorate, causing leakage and
poor brake performance.
• Refill with the same type of brake
fluid;
mixing fluids may result in a
harmful chemical reaction and
lead to poor performance.
• Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the flu-
id and may result in vapor lock.
Brake fluid may erode painted sur-
faces or plastic parts. Always
clean up spilled fluid immediately.
A. Front
B. Rear
2. Air bleed:
• Brake system
Refer to "BLEEDING THE HY-
DRAULIC BRAKE SYSTEM" sec-
tion in the CHAPTER 3.
3. Inspect:
• Brake fluid level
Fluid at lower level→Fill up.
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section in
the CHAPTER 3.
4. Install:
• Reservoir float (front brake)
• Diaphragm
• Brake master cylinder cap "1"
• Screw (brake master cylinder
cap) "2" Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Screw (brake hose hold-
er):
3 Nm (0.3 m•kg, 2.2
ft•lb)
Recommended brake flu-
id:
DOT #4
Screw (bolt) {brake mas-
ter cylinder cap}:
2 Nm (0.2 m•kg, 1.4
ft•lb)