engine YAMAHA WR 250F 2017 Owner's Manual
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Page 50 of 432

MOTORCYCLE CARE AND STORAGE
1-36
EAS2GBB058
MOTORCYCLE CARE AND STOR-
AGE
EAS2GBB059CARE
While the open design of a motorcycle reveals 
the attractiveness of the technology, it also 
makes it more vulnerable. Rust and corrosion 
can develop even if high-quality components 
are used. A rusty exhaust pipe may go unno-
ticed on a car, however, it detracts from the 
overall appearance of a motorcycle. Frequent 
and proper care does not only comply with the 
terms of the warranty, but it will also keep your 
motorcycle looking good, extend its life and op-
timize its performance.
Before cleaning
1. Cover the muffler outlet with a plastic bag af-
ter the engine has cooled down.
2. Make sure that all caps and covers as well 
as all electrical couplers and connectors, in-
cluding the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt, like oil 
burnt onto the crankcase, with a degreasing 
agent and a brush, but never apply such 
products onto seals, gaskets, sprockets, the 
drive chain and wheel axles. Always rinse 
the dirt and degreaser off with water.
Cleaning
ECA
NOTICE
• Avoid using strong acidic wheel cleaners, 
especially on spoked wheels. If such prod-
ucts are used on hard-to-remove dirt, do 
not leave the cleaner on the affected area 
any longer than instructed. Also, thor-
oughly rinse the area off with water, imme-
diately dry it, and then apply a corrosion 
protection spray.
• Improper cleaning can damage plastic 
parts (such as cowlings, panels, wind-
shields, headlight lenses, meter lenses, 
etc.) and the mufflers. Use only a soft, 
clean cloth or sponge with water to clean 
plastic. However, if the plastic parts can-
not be thoroughly cleaned with water, di-
luted mild detergent with water may be 
used. Be sure to rinse off any detergent 
residue using plenty of water, as it is 
harmful to plastic parts.• Do not use any harsh chemical products 
on plastic parts. Be sure to avoid using 
cloths or sponges which have been in con-
tact with strong or abrasive cleaning prod-
ucts, solvent or thinner, fuel (gasoline), 
rust removers or inhibitors, brake fluid, 
antifreeze or electrolyte.
• Do not use high-pressure washers or 
steam-jet cleaners since they cause water 
seepage and deterioration in the following 
areas: seals (of wheel and swingarm bear-
ings, fork and brakes), electric compo-
nents (couplers, connectors, instruments, 
switches and lights), breather hoses and 
vents.
• For motorcycles equipped with a wind-
shield: Do not use strong cleaners or hard 
sponges as they will cause dulling or 
scratching. Some cleaning compounds for 
plastic may leave scratches on the wind-
shield. Test the product on a small hidden 
part of the windshield to make sure that it 
does not leave any marks. If the wind-
shield is scratched, use a quality plastic 
polishing compound after washing.
After normal use
Remove dirt with warm water, a mild detergent, 
and a soft, clean sponge, and then rinse thor-
oughly with clean water. Use a toothbrush or 
bottlebrush for hard-to-reach areas. Stubborn 
dirt and insects will come off more easily if the 
area is covered with a wet cloth for a few min-
utes before cleaning.
After riding in the rain, near the sea or on salt-
sprayed roads
Since sea salt or salt sprayed on roads during 
winter are extremely corrosive in combination 
with water, carry out the following steps after 
each ride in the rain, near the sea or on salt-
sprayed roads.
TIP
Salt sprayed on roads in the winter may remain 
well into spring.
1. Clean the motorcycle with cold water and a 
mild detergent, after the engine has cooled 
down.
NOTICE: Do not use warm water since it 
increases the corrosive action of the salt. 
Page 51 of 432

MOTORCYCLE CARE AND STORAGE
1-37
2. Apply a corrosion protection spray on all 
metal, including chrome- and nickel-plated, 
surfaces to prevent corrosion.
After cleaning
1. Dry the motorcycle with a chamois or an ab-
sorbing cloth.
2. Immediately dry the drive chain and lubri-
cate it to prevent it from rusting.
3. Use a chrome polish to shine chrome, alumi-
num and stainless- steel parts, including the 
exhaust system. (Even the thermally in-
duced discoloring of stainless- steel exhaust 
systems can be removed through polishing.)
4. To prevent corrosion, it is recommended to 
apply a corrosion protection spray on all 
metal, including chrome- and nickel-plated, 
surfaces.
5. Use spray oil as a universal cleaner to re-
move any remaining dirt.
6. Touch up minor paint damage caused by 
stones, etc.
7. Wax all painted surfaces.
8. Let the motorcycle dry completely before 
storing or covering it.
EWA
WARNING
Contaminants on the brakes or tires can 
cause loss of control.
• Make sure that there is no oil or wax on the 
brakes or tires.
• If necessary, clean the brake discs and 
brake linings with a regular brake disc 
cleaner or acetone, and wash the tires with 
warm water and a mild detergent. Before 
riding at higher speeds, test the motorcy-
cle’s braking performance and cornering 
behavior.
ECA
NOTICE
• Apply spray oil and wax sparingly and 
make sure to wipe off any excess.
• Never apply oil or wax to any rubber and 
plastic parts, but treat them with a suitable 
care product.
• Avoid using abrasive polishing com-
pounds as they will wear away the paint.
TIP
• Consult a Yamaha dealer for advice on what 
products to use.
• Washing, rainy weather or humid climates 
can cause the headlight lens to fog. Turning 
the headlight on for a short period of time will 
help remove the moisture from the lens.
EAS2GBB060STORAGE
Short-term
Always store your motorcycle in a cool, dry 
place and, if necessary, protect it against dust 
with a porous cover. Be sure the engine and the 
exhaust system are cool before covering the 
motorcycle.
ECA
NOTICE
• Storing the motorcycle in a poorly ventilat-
ed room or covering it with a tarp, while it 
is still wet, will allow water and humidity to 
seep in and cause rust.
• To prevent corrosion, avoid damp cellars, 
stables (because of the presence of am-
monia) and areas where strong chemicals 
are stored.
Long-term
Before storing your motorcycle for several 
months: 
1. Follow all the instructions in the “Care” sec-
tion of this chapter.
2. Fill up the fuel tank and add fuel stabilizer (if 
available) to prevent the fuel tank from rust-
ing and the fuel from deteriorating.
3. Perform the following steps to protect the 
cylinder, piston rings, etc. from corrosion.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the 
spark plug bore.
c. Install the spark plug cap onto the spark 
plug, and then place the spark plug on the 
cylinder head so that the electrodes are 
grounded. (This will limit sparking during the 
next step.)
d. Turn the engine over several times with the 
starter. (This will coat the cylinder wall with 
oil.) 
Page 52 of 432

MOTORCYCLE CARE AND STORAGE
1-38
e. Remove the spark plug cap from the spark 
plug, and then install the spark plug and the 
spark plug cap. WARNING! To prevent 
damage or injury from sparking, make 
sure to ground the spark plug electrodes 
while turning the engine over.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4. Lubricate all control cables and the pivoting 
points of all levers and pedals as well as of 
the sidestand/ centerstand.
5. Check and, if necessary, correct the tire air 
pressure, and then lift the motorcycle so that 
both of its wheels are off the ground. Alter-
natively, turn the wheels a little every month 
in order to prevent the tires from becoming 
degraded in one spot.
6. Cover the muffler outlet with a plastic bag to 
prevent moisture from entering it.
7. Remove the battery and fully charge it. Store 
it in a cool, dry place and charge it once a 
month. Do not store the battery in an exces-
sively cold or warm place [less than 0 °C (30 
°F) or more than 30 °C (90 °F)]. For more in-
formation on storing the battery, See page 
9-69.
TIP
Make any necessary repairs before storing the 
motorcycle. 
Page 53 of 432

2
SPECIFICATIONS
GENERAL SPECIFICATIONS......................................................................... 2-1
ENGINE SPECIFICATIONS............................................................................. 2-2
CHASSIS SPECIFICATIONS........................................................................... 2-7
ELECTRICAL SPECIFICATIONS.................................................................. 2-10
TIGHTENING TORQUES............................................................................... 2-12
GENERAL TIGHTENING TORQUE SPECIFICATIONS .......................... 2-12
ENGINE TIGHTENING TORQUES .......................................................... 2-13
CHASSIS TIGHTENING TORQUES ........................................................ 2-16
LUBRICATION POINTS AND LUBRICANT TYPES..................................... 2-20
ENGINE .................................................................................................... 2-20
CHASSIS .................................................................................................. 2-21
LUBRICATION SYSTEM CHART AND DIAGRAMS..................................... 2-23
LUBRICATION DIAGRAMS ..................................................................... 2-23
CABLE ROUTING DIAGRAM........................................................................ 2-31 
Page 55 of 432

ENGINE SPECIFICATIONS
2-2
EAS2GBB062
ENGINE SPECIFICATIONS
Engine
Engine type Liquid cooled 4-stroke, DOHC
Displacement 250 cm
3
Number of cylinders Single cylinder
Bore  stroke 77.0  53.6 mm (3.03  2.11 in)
Compression ratio 13.5:1
Starting system Electric starter and kickstarter
Fuel
Recommended fuel Premium unleaded gasoline only
Fuel tank capacity 7.5 L (2.0 US gal, 1.7 Imp.gal)
Fuel reserve amount 2.1 L (0.55 US gal, 0.46 lmp.gal)
Engine oil
Lubrication system Wet sump
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
Engine oil quantity
Quantity (disassembled) 1.10 L (1.16 US qt, 0.97 Imp.qt)
Oil change 0.83 L (0.88 US qt, 0.73 Imp.qt)
With oil filter removal 0.85 L (0.90 US qt, 0.75 Imp.qt)
Oil filter
Oil filter type Paper
Bypass valve opening pressure 40.0–80.0 kPa (0.40–0.80 kgf/cm
2,
5.8–11.6 psi)
Oil pump
Oil pump type Trochoid
Inner-rotor-to-outer-rotor-tip clearance 0.000–0.150 mm (0.0000–0.0059 in)
Limit 0.23 mm (0.0091 in)
Outer-rotor-to-oil-pump-housing clearance 0.13–0.18 mm (0.0051–0.0071 in)
Limit 0.25 mm (0.0098 in)
Oil-pump-housing-to-inner-and-outer-rotor 
clearance 0.06–0.11 mm (0.0024–0.0043 in)
Limit 0.18 mm (0.0071 in)
Cooling system
Radiator (including all routes) 1.00 L (1.06 US qt, 0.88 Imp.qt)
Radiator capacity 0.56 L (0.59 US qt, 0.49 Imp.qt)
Radiator cap valve opening pressure 107.9–137.3 kPa (1.08–1.37 kg/cm
2,
15.6–19.9 psi)
Radiator core
Width 112.6 mm (4.43 in)
Height 235.0 mm (9.25 in)
Depth 28.0 mm (1.10 in)
Water pump
Water pump type Single suction centrifugal pump
Spark plug(s)
Manufacturer/model NGK/LMAR8G
Spark plug gap 0.7–0.8 mm (0.028–0.031 in) 
Page 56 of 432

ENGINE SPECIFICATIONS
2-3
Cylinder head
Combustion chamber volume 12.07–12.87 cm3 (0.74–0.79 cu.in)
Warpage limit 0.05 mm (0.0020 in)
Camshaft
Drive system Chain drive (left)
Camshaft cap inside diameter 22.000–22.021 mm (0.8661–0.8670 in)
Camshaft journal diameter 21.959–21.972 mm (0.8645–0.8650 in)
Camshaft-journal-to-camshaft-cap clearance 0.028–0.062 mm (0.0011–0.0024 in)
Camshaft lobe dimensions
Lobe height (Intake) 31.730–31.830 mm (1.2492–1.2531 in)
Limit 31.630 mm (1.2453 in)
Base circle diameter (Intake) 22.450–22.550 mm (0.8839–0.8878 in)
Limit 22.350 mm (0.8799 in)
Lobe height (Exhaust) 33.370–33.470 mm (1.3138–1.3177 in)
Limit 33.270 mm (1.3098 in)
Base circle diameter (Exhaust) 25.211–25.311 mm (0.9926–0.9965 in)
Limit 25.111 mm (0.9886 in)
Camshaft runout limit 0.030 mm (0.0012 in)
Timing chain
Tensioning system Automatic
Valve, valve seat, valve guide
Valve clearance (cold)
Intake 0.12–0.19 mm (0.0047–0.0075 in)
Exhaust 0.17–0.24 mm (0.0067–0.0094 in)
Valve dimensions
Valve head diameter (intake) 30.90–31.10 mm (1.2165–1.2244 in)
Valve head diameter (exhaust) 24.90–25.10 mm (0.9803–0.9882 in)
Valve face width (intake) 1.697 mm (0.0668 in)
Valve face width (exhaust) 1.909 mm (0.0752 in)
Valve seat contact width (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Valve seat contact width (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Valve margin thickness (intake) 1.20 mm (0.0472 in)
Valve margin thickness (exhaust) 0.85 mm (0.0335 in)
Valve stem diameter (intake) 4.975–4.990 mm (0.1959–0.1965 in)
Limit 4.945 mm (0.1947 in)
Valve stem diameter (exhaust) 4.460–4.475 mm (0.1756–0.1762 in)
Limit 4.430 mm (0.1744 in)
Valve guide inside diameter (intake) 5.000–5.012 mm (0.1969–0.1973 in)
Limit 5.050 mm (0.1988 in)
Valve guide inside diameter (exhaust) 4.500–4.512 mm (0.1772–0.1776 in)
Limit 4.550 mm (0.1791 in)
Valve-stem-to-valve-guide clearance (intake) 0.010–0.037 mm (0.0004–0.0015 in)
Limit 0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clearance (exhaust) 0.025–0.052 mm (0.0010–0.0020 in)
Limit 0.100 mm (0.0039 in)
Valve stem runout 0.010 mm (0.0004 in) 
Page 57 of 432

ENGINE SPECIFICATIONS
2-4
Valve spring
Free length (intake) 36.69 mm (1.44 in)
Limit 34.85 mm (1.37 in)
Free length (exhaust) 34.86 mm (1.37 in)
Limit 33.11 mm (1.30 in)
Installed length (intake) 31.40 mm (1.24 in)
Installed length (exhaust) 28.50 mm (1.12 in)
Spring rate K1 (intake) 29.65 N/mm (3.02 kgf/mm, 169.30 lbf/in)
Spring rate K2 (intake) 39.31 N/mm (4.01 kgf/mm, 224.46 lbf/in)
Spring rate K1 (exhaust) 23.11 N/mm (2.36 kgf/mm, 131.96 lbf/in)
Spring rate K2 (exhaust) 30.88 N/mm (3.15 kgf/mm, 176.32 lbf/in)
Installed compression spring force (intake) 146.00–168.00 N (14.89–17.13 kgf, 
32.82–37.77 lbf)
Installed compression spring force (exhaust) 137.00–157.00 N (13.97–16.01 kgf, 
30.80–35.29 lbf)
Spring tilt (intake) 2.5 °/1.6 mm (2.5 °/0.06 in)
Spring tilt (exhaust) 2.5 °/1.5 mm (2.5 °/0.06 in)
Winding direction (intake) Clockwise
Winding direction (exhaust) Clockwise
Cylinder
Bore 77.000–77.010 mm (3.0315–3.0319 in)
Taper limit 0.050 mm (0.0020 in)
Out of round limit 0.050 mm (0.0020 in)
Piston
Piston-to-cylinder clearance 0.030–0.055 mm (0.0012–0.0022 in)
Limit 0.15 mm (0.006 in)
Diameter 76.955–76.970 mm (3.0297–3.0303 in)
Measuring point (from piston skirt bottom) 6.0 mm (0.24 in)
Offset 0.00 mm (0.0000 in)
Piston pin bore inside diameter 16.002–16.013 mm (0.6300–0.6304 in)
Limit 16.043 mm (0.6316 in)
Piston pin outside diameter 15.991–16.000 mm (0.6296–0.6299 in)
Limit 15.971 mm (0.6288 in)
Piston ring
Top ring
Ring type Barrel
Dimensions (B  T) 0.90  2.70 mm (0.04  0.11 in)
End gap (installed) 0.15–0.25 mm (0.0059–0.0098 in)
Limit 0.50 mm (0.0197 in)
Ring side clearance 0.030–0.065 mm (0.0012–0.0026 in)
Limit 0.115 mm (0.0045 in)
Oil ring
Dimensions (B  T) 1.50  2.25 mm (0.06  0.89 in)
End gap (installed) 0.10–0.35 mm (0.0039–0.0138 in)
Crankshaft
Crank assembly width 55.95–56.00 mm (2.203–2.205 in)
Runout limit 0.030 mm (0.0012 in)
Big end side clearance 0.150–0.450 mm (0.0059–0.0177 in)
Balancer
Balancer drive method Gear 
Page 58 of 432

ENGINE SPECIFICATIONS
2-5
Clutch
Clutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 7.0–12.0 mm (0.28–0.47 in)
Friction plate 1 thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 4 pcs
Friction plate 2 thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 5 pcs
Clutch plate thickness 1.10–1.30 mm (0.043–0.051 in)
Plate quantity 8 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch spring free length 47.80 mm (1.88 in)
Limit 45.41 mm (1.79 in)
Spring quantity 5 pcs
Push rod bending limit 0.30 mm (0.012 in)
Transmission
Transmission type Constant mesh 6-speed
Primary reduction system Spur gear
Primary reduction ratio 3.353 (57/17)
Final drive Chain
Secondary reduction ratio 3.846 (50/13)
Operation Left foot operation
Gear ratio
1st 2.385 (31/13)
2nd 1.813 (29/16)
3rd 1.444 (26/18)
4th 1.143 (24/21)
5th 0.957 (22/23)
6th 0.815 (22/27)
Main axle runout limit 0.08 mm (0.0032 in)
Drive axle runout limit 0.08 mm (0.0032 in)
Shifting mechanism
Shift mechanism type Shift drum and guide bar
Shift fork guide bar bending limit 0.050 mm (0.0020 in)
Shift fork thickness 4.85 mm (0.1909 in)
Decompression device
Device type Auto decomp
Air filter
Air filter element Wet element
Air filter oil grade Yamaha foam air filter oil or other quality foam 
air filter oil
Fuel pump
Pump type Electrical
Fuel injector
Model/quantity 30NA-FZ31/1
Resistance 12.0  
Page 59 of 432

ENGINE SPECIFICATIONS
2-6
Throttle body
Type/quantity 30RA-A95R/1
ID mark 2GB1 00
Fuel line pressure (at idle) 300.0–390.0 kPa (3.00–3.90 kgf/cm
2, 
43.5–56.6 psi)
Throttle position sensor
Resistance 6.30 k
Output voltage (at idle) 0.48–0.52 V
Fuel injection sensor
Crankshaft position sensor resistance 228–342 
Intake air pressure sensor output voltage 3.61–3.67 V at 101.3 kPa (3.61–3.67 V at 
1.01 kgf/cm
2, 3.61–3.67 V at 14.7 psi)
Intake air temperature sensor resistance 5400.0–6600.0  at 0 °C (5400.0–6600.0  
 at 32 °F)
289–391  at 80 °C (289–391  at 176 °F)
Coolant temperature sensor resistance 2512–2777  at 20 °C (2512–2777  at 68 °F)
210–220  at 100 °C (210–220  at 212 °F)
Idling condition
Engine idling speed 1900–2100 r/min
CO% 3.0–4.0 % (USA) (CAN)
Intake vacuum 27.3 kPa (205 mmHg, 8.1 inHg) (USA) (CAN)
Water temperature 70–90 °C (158–194 °F)
Oil temperature 70–80 °C (158–176 °F)
Throttle grip free play 3.0–6.0 mm (0.12–0.24 in) 
Page 63 of 432

ELECTRICAL SPECIFICATIONS
2-10
EAS2GBB064
ELECTRICAL SPECIFICATIONS
Voltage
System voltage 12 V
Ignition system
Ignition system TCI
Advancer type Digital
Ignition timing (B.T.D.C.) 10.0 ° at 2000 r/min
Engine control unit
Model/manufacturer 2GB0/YAMAHA (USA) (CAN)
2GB1/YAMAHA (EUR) (AUS) (NZL) (ZAF)
Ignition coil
Minimum ignition spark gap 6.0 mm (0.24 in)
Primary coil resistance 2.16–2.64 
Secondary coil resistance 8.64–12.96 k
Spark plug cap
Resistance 7.50–12.50 k
Lean angle sensor output voltage
Operating angle 45 °
Output voltage up to operating angle 0.4–1.4 V
Output voltage over operating angle 3.7–4.4 V
AC magneto
Standard output 14.0 V, 160 W at 5000 r/min
Stator coil resistance 0.528–0.792  (W–W)
Rectifier/regulator
Regulator type Three-phase
Regulated voltage (DC) 14.1–14.9 V
Rectifier capacity (DC) 35.0 A
Battery
Model YTZ7S (F)
Voltage, capacity 12 V, 6.0 Ah (10 HR)
Specific gravity 1.31
Manufacturer GS YUASA
Ten hour rate charging current 0.60 A
Headlight
Bulb type Halogen bulb
Bulb voltage, wattage  quantity
Headlight HS1, 35.0 W/35.0 W  1
Tail/brake light LED
Meter lighting EL (Electroluminescent)
Indicator light
Fuel level warning light 12 V, 1.7 W  1
Engine trouble warning light 12 V, 1.7 W  1
Electric starting system
System type Constant mesh