2017 YAMAHA WR 250F Owners Manual

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

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 

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)

CHASSIS SPECIFICATIONS
2-7
EAS2GBB063
CHASSIS SPECIFICATIONS
Chassis
Frame type Semi double cradle
Caster angle 26.3 °
Trail 114 mm (4.5 in)
Front wheel
Wheel type Spoke wheel
Rim size 1.60 21
Rim material Aluminum
Wheel travel 310 mm (12.2 in)
Radial wheel runout limit 2.0 mm (0.08 in)
Lateral wheel runout limit 2.0 mm (0.08 in)
Wheel axle bending limit 0.50 mm (0.02 in)
Rear wheel
Wheel type Spoke wheel
Rim size 2.15  18
Rim material Aluminum
Wheel travel 318 mm (12.5 in)
Radial wheel runout limit 2.0 mm (0.08 in)
Lateral wheel runout limit 2.0 mm (0.08 in)
Wheel axle bending limit 0.50 mm (0.02 in)
Front tire
Type With tube
Size 80/100-21 51M (USA) (CAN)
90/90-21 M/C 54M M+S (EUR) (AUS) (NZL)
(ZAF)
Manufacturer/model DUNLOP/MX51FA (USA) (CAN)
PIRELLI/SIX DAYS EXTREME (EUR) (AUS)
(NZL) (ZAF)
Rear tire
Type With tube
Size 110/100-18 64M (USA) (CAN)
130/90-18 M/C 69M M+S (EUR) (AUS) (NZL)
(ZAF)
Manufacturer/model DUNLOP/MX51 (USA) (CAN)
PIRELLI/SIX DAYS EXTREME (EUR) (AUS)
(NZL) (ZAF)
Tire air pressure (measured on cold tires)
Front 100 kPa (1.00 kgf/cm2, 15 psi)
Rear 100 kPa (1.00 kgf/cm2, 15 psi)
Front brake
Type Hydraulic single disc brake
Operation Right hand operation
Front disc brake
Disc outside diameter  thickness 270.0  3.0 mm (10.63  0.12 in)
Brake disc thickness limit 2.5 mm (0.10 in)
Brake pad lining thickness 4.4 mm (0.17 in)
Limit 1.0 mm (0.04 in)
Master cylinder inside diameter 9.52 mm (0.37 in)
Caliper cylinder inside diameter 22.65 mm, 22.65 mm (0.89 in, 0.89 in)
Specified brake fluid DOT 4

CHASSIS SPECIFICATIONS
2-8
Rear brake
Type Hydraulic single disc brake
Operation Right foot operation
Brake pedal position 5.0 mm (0.20 in)
Rear disc brake
Disc outside diameter  thickness 245.0  4.0 mm (9.65  0.16 in)
Brake disc thickness limit 3.5 mm (0.14 in)
Brake disc runout limit (as measured on wheel) 0.15 mm (0.0059 in)
Brake pad lining thickness 6.4 mm (0.25 in)
Limit 1.0 mm (0.04 in)
Master cylinder inside diameter 11.0 mm (0.43 in)
Caliper cylinder inside diameter 25.40 mm (1.00 in)
Specified brake fluid DOT 4
Steering
Steering bearing type Taper roller bearing
Center to lock angle (left) 43.0 °
Center to lock angle (right) 43.0 °
Front suspension
Type Telescopic fork
Spring/shock absorber type Coil spring/hydraulic damper
Front fork travel 310 mm (12.2 in)
Fork spring free length 470.0 mm (18.50 in)
Limit 465.0 mm (18.31 in)
Fork spring installed length 470.0 mm (18.50 in)
Spring rate K1 4.40 N/mm (0.45 kgf/mm, 25.12 lbf/in)
Spring stroke K1 0.0–310.0 mm (0.00–12.20 in)
Inner tube outer diameter 48 mm (1.9 in)
Inner tube bending limit 0.2 mm (0.01 in)
Optional spring available Yes
Recommended oil Yamaha Suspension Oil S1
Quantity 540.0 cm
3 (18.26 US oz, 19.05 Imp.oz)
Rebound damping adjusting positions
Minimum 20 clicks out*
Standard 10 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in
Compression damping adjusting positions
Minimum 20 clicks out*
Standard 11 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in

CHASSIS SPECIFICATIONS
2-9
Rear suspension
Type Swingarm (link suspension)
Spring/shock absorber type Coil spring/gas-hydraulic damper
Rear shock absorber assembly travel 126.0 mm (4.96 in)
Spring free length 275.0 mm (10.83 in)
Spring installed length 265.0 mm (10.43 in)
Spring rate K1 54.00 N/mm (5.51 kgf/mm, 308.34 lbf/in)
Spring stroke K1 0.0–150.0 mm (0.00–5.91 in)
Optional spring available Yes
Enclosed gas/air pressure (STD) 980 kPa (9.8 kgf/cm
2, 139.4 psi)
Spring preload adjusting positions
Minimum Position in which the spring is turned in 1.5 mm
(0.06 in) from its free length.
Standard Position in which the spring is turned in 10 mm
(0.39 in) from its free length.
Maximum Position in which the spring is turned in 18 mm
(0.71 in) from its free length.
Rebound damping adjusting positions
Minimum 30 clicks out*
Standard 14 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in
Compression damping setting
(for fast compression damping)
Minimum 2 turns out*
Standard 1-1/4 turns out*
Maximum Fully turned in
* With the adjuster fully turned in
Compression damping setting
(for slow compression damping)
Minimum 20 clicks out*
Standard 10 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in
Swingarm
Swingarm end free play limit (radial) 1.0 mm (0.04 in)
Swingarm end free play limit (axial) 0.2–0.9 mm (0.01–0.04 in)
Drive chain
Size DID520VM2
Number of links 114
Drive chain slack (on a suitable stand) 50.0–60.0 mm (1.97–2.36 in)
15-link length limit 239.3 mm (9.42 in)

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

ELECTRICAL SPECIFICATIONS
2-11
Starter motor
Power output 0.35 kW
Armature coil resistance 0.0189–0.0231 
Brush overall length 7.0 mm (0.28 in)
Limit 3.50 mm (0.14 in)
Brush spring force 3.92–5.88 N (400–600 gf, 14.11–21.17 oz)
Commutator diameter 17.6 mm (0.69 in)
Limit 16.6 mm (0.65 in)
Mica undercut (depth) 1.50 mm (0.06 in)
Fuel sender unit
Sender unit resistance (thermistor) 1350–1900 
Starter relay
Amperage 180.0 A
Coil resistance 4.18–4.62 
Starting circuit cut-off relay
Coil resistance 75.6–92.5 
Headlight relay
Coil resistance 86.4–105.6 
Fuses
Main fuse 15.0 A
Radiator fan motor fuse 5.0 A
Spare fuse 15.0 A