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SPECMAINTENANCE SPECIFICATIONS (WR426F)
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear brake hose union bolt (master cylinder)M10 ´ 1.25 1 30 3.0 22
Rear wheel axle and nut M20 ´ 1.5 1 125 12.5 90
Driven sprocket and wheel hub M8 ´ 1.25 6 42 4.2 30
Nipple (spoke) — 72 3 0.3 2.2
Disc cover and rear brake caliper M6 ´ 1.0 2 7 0.7 5.1
Protector and rear brake caliper M6 ´ 1.0 2 7 0.7 5.1
Engine mounting:
Engine bracket and frame M8 ´ 1.25 7 34 3.4 24
Engine and frame (front) M10 ´ 1.25 1 69 6.9 50
Engine and frame (upper) M10 ´ 1.25 1 55 5.5 40
Engine and frame (lower) M10 ´ 1.25 1 69 6.9 50
Engine guard (left and right) M8 ´ 1.25 2 23 2.3 17
Pivot shaft and nut M16 ´ 1.5 1 85 8.5 61
Relay arm and swingarm M14 ´ 1.5 1 80 8.0 58
Relay arm and connecting rod M14 ´ 1.5 1 80 8.0 58
Connecting rod and frame M14 ´ 1.5 1 80 8.0 58
Rear shock absorber and frame M10 ´ 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 ´ 1.25 1 53 5.3 38
Rear frame and frame M8 ´ 1.25 3 29 2.9 21
Swingarm and brake hose holder M5 ´ — 4 4 0.4 2.9
Drive chain tensioner mounting M8 ´ 1.25 2 19 1.9 13
Chain support and swingarm M6 ´ 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 ´ 0.8 4 6 0.6 4.3
Fuel tank mounting M6 ´ 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 ´ 1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M6 ´ 1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M6 ´ 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 ´ 1.0 4 7 0.7 5.1
Seat mounting M8 ´ 1.25 2 23 2.3 17
Side cover mounting M6 ´ 1.0 2 7 0.7 5.1
Air scoop and fuel tank M6 ´ 1.0 4 4 0.4 2.9
Air scoop and radiator panel (lower) M6 ´ 1.0 2 4 0.4 2.9
Front fender mounting M6 ´ 1.0 4 7 0.7 5.1
Rear fender mounting M6 ´ 1.0 4 7 0.7 5.1
Headlight stay (under) and under bracket M6 ´ 1.0 2 7 0.7 5.1
Headlight M6 ´ 1.0 3 7 0.7 5.1
Tail light M6 ´ 1.0 3 4 0.4 2.9
Tail light lead clamp and rear fender M4 ´ 1.59 2 1 0.1 0.7
Coolant reservoir tank M6 ´ 1.0 2 7 0.7 5.1
Sidestand bracket and frame M10 ´ 1.25 2 64 6.4 46
Sidestand mounting M10 ´ 1.25 1 64 6.4 46
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SPECMAINTENANCE SPECIFICATIONS (WR426F)
EC212300
ELECTRICAL
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model/manufacturer F5NG 00/YAMAHA ----
Source coil 1 resistance (color) 640 ~ 960 W at 20 ˚C (68 ˚F)
(Green – Brown)----
Source coil 2 resistance (color) 464 ~ 696 W at 20 ˚C (68 ˚F)
(Green – Pink)----
Lighting coil resistance (color) 0.16 ~ 0.24 W at 20 ˚C (68 ˚F)
(Black – Yellow)
Pickup coil resistance (color) 248 ~ 372 W at 20 ˚C (68 ˚F)
(White – Red)----
CDI unit-model/manufacturer 5NG-00/YAMAHA
(For USA)
5NG-10/YAMAHA
(Except for USA)----
Ignition coil:
Model/manufacturer 5BE-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary winding resistance 0.20 ~ 0.30 W at 20 ˚C (68 ˚F) ----
Secondary winding resistance 9.5 ~ 14.3 kW at 20 ˚C (68 ˚F) ----
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Stator M6 ´ 1.0 3 10 1.0 7.2
Rotor M10 ´ 1.25 1 48 4.8 35
Ignition coil M6 ´ 1.0 2 7 0.7 5.1
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SPECGENERAL SPECIFICATIONS (WR400F)
EC211000
GENERAL SPECIFICATIONS (WR400F)
Model name: WR400F (EUROPE)
WR400FN (AUS)
Model code number: 5GS9
Dimensions:
Overall length 2,171 mm (85.5 in)
Overall width 827 mm (32.6 in)
Overall height 1,303 mm (51.3 in)
Seat height 998 mm (39.3 in)
Wheelbase 1,490 mm (58.7 in)
Minimum ground clearance 373 mm (14.7 in)
Basic weight:
With oil and full fuel tank 121.5 kg (268 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder, forward inclined
Displacement 399 cm
3 (14.1 Imp oz, 13.5 US oz)
Bore ´ stroke 92.0 ´ 60.1 mm (3.62 ´ 2.37 in)
Compression ratio 12.5 : 1
Starting system Kick starter
Lubrication system: Dry sump
Oil type or grade:
Engine oil
API “SH” or higher grade
Oil capacity:
Engine oil
Periodic oil change 1.5 L (1.32 Imp qt, 1.59 US qt)
With oil filter replacement 1.6 L (1.41 Imp qt, 1.69 US qt)
Total amount 1.7 L (1.50 Imp qt, 1.80 US qt)
Coolant capacity (including all routes): 1.2 L (1.06 Imp qt, 1.27 US qt)
Air filter: Wet type element
-20
-4-10
140
3010
5020
6830
8640 50
104
122¡CTemp.
¡F
10W-30
10W-40
20W-40
20W-50
15W-40
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SPECGENERAL SPECIFICATIONS (WR400F)
Fuel:
Type Premium unleaded fuel with a research octane
number of 95 or higher. (Except for AUS)
Unleaded fuel only (For AUS)
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
Reserve 1.4 L (0.31 Imp gal, 0.37 US gal)
Carburetor:
Type FCR-MX39
Manufacturer KEIHIN
Spark plug:
Type/manufacturer CR8E/NGK
U24ESR-N/DENSO
Gap 0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 62/21 (2.952)
Secondary reduction system Chain drive
Secondary reduction ratio 50/14 (3.571)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 29/12 (2.416)
2nd 26/15 (1.733)
3rd 21/16 (1.312)
4th 21/20 (1.050)
5th 21/25 (0.840)
Chassis:
Frame type Semi double cradle
Caster angle 27.8˚
Trail 123 mm (4.84 in)
Tire:
Type With tube
Size (front) 90/90-21 54R
Size (rear) 130/90-18 69R
Tire pressure (front and rear) 100 kPa (1.0 kg/cm
2, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
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SPECGENERAL SPECIFICATIONS (WR400F)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
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SPECMAINTENANCE SPECIFICATIONS (WR400F)
MAINTENANCE SPECIFICATIONS (WR400F)
ENGINE
Item Standard Limit
Cylinder head:
Warp limit ---- 0.05 mm
(0.002 in)
Cylinder:
Bore size 92.00 ~ 92.01 mm
(3.6220 ~ 3.6224 in)----
Out of round limit ---- 0.05 mm
(0.002 in)
Camshaft:
Drive method Chain drive (left) ----
Camshaft cap inside diameter 22.000 ~ 22.021 mm
(0.8661 ~ 0.8670 in)----
Camshaft bearing diameter 21.967 ~ 21.980 mm
(0.8648 ~ 0.8654 in)----
Camshaft-to-cap clearance 0.020 ~ 0.054 mm
(0.0008 ~ 0.0021 in)0.08 mm
(0.003 in)
Cam dimensions
Intake “A” 31.7 ~ 31.8 mm
(1.248 ~ 1.252 in)31.6 mm
(1.244 in)
“B” 22.95 ~ 23.05 mm
(0.9035 ~ 0.9075 in)22.85 mm
(0.900 in)
Exhaust “A” 31.2 ~ 31.3 mm
(1.2283 ~ 1.2323 in)31.1 mm
(1.224 in)
“B” 22.95 ~ 23.05 mm
(0.9035 ~ 0.9075 in)22.85 mm
(0.900 in)
Camshaft runout limit ---- 0.03 mm
(0.0012 in)
A
B
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SPECMAINTENANCE SPECIFICATIONS (WR400F)
Cam chain:
Cam chain type/No. of links 92RH2010-120MPX/120 ----
Cam chain adjustment method Automatic ----
Valve, valve seat, valve guide:
Valve clearance (cold) IN 0.10 ~ 0.15 mm
(0.0039 ~ 0.0059 in)----
EX 0.20 ~ 0.25 mm
(0.0079 ~ 0.0098 in)----
Valve dimensions:
“A” head diameter IN 26.9 ~ 27.1 mm
(1.0591 ~ 1.0669 in)----
EX 27.9 ~ 28.1 mm
(1.0984 ~ 1.1063 in)----
“B” face width IN 2.26 mm (0.089 in) ----
EX 2.26 mm (0.089 in) ----
“C” seat width IN 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
“D” margin thickness IN 1 mm (0.0394 in) 0.85 mm
(0.033 in)
EX 1 mm (0.0394 in) 0.85 mm
(0.033 in)
Stem outside diameter IN 4.475 ~ 4.490 mm
(0.1762 ~ 0.1768 in)4.445 mm
(0.1750 in)
EX 4.965 ~ 4.980 mm
(0.1955 ~ 0.1961 in)4.935 mm
(0.1943 in)
Guide inside diameter IN 4.500 ~ 4.512 mm
(0.1772 ~ 0.1776 in)4.550 mm
(0.1791 in)
EX 5.000 ~ 5.012 mm
(0.1969 ~ 0.1973 in)5.050 mm
(0.1988 in)
Stem-to-guide clearance IN 0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)0.08 mm
(0.003 in)
EX 0.020 ~ 0.047 mm
(0.0008 ~ 0.0019 in)0.10 mm
(0.004 in)
Stem runout limit ---- 0.01 mm
(0.0004 in) Item Standard Limit
Head Diameter
B
Face WidthC
Seat Width
D
Margin ThicknessA
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SPECMAINTENANCE SPECIFICATIONS (WR400F)
Valve seat width IN0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
Valve spring:
Free length IN 41.36 mm (1.63 in) 39.3 mm
(1.55 in)
EX 43.60 mm (1.72 in) 41.4 mm
(1.63 in)
Set length (valve closed) IN 32.86 mm (1.29 in) ----
EX 35.38 mm (1.39 in) ----
Compressed pressure
(installed) IN 112.8 ~ 129.8 N
(11.5 ~ 13.2 kg, 25.35 ~ 29.10 lb)----
EX 116.3 ~ 133.9 N
(11.9 ~ 13.7 kg, 26.23 ~ 30.20 lb)----
Tilt limit IN ----2.5˚/1.8 mm
(2.5˚/0.071 in)
EX ----2.5˚/1.9 mm
(2.5˚/0.075 in)
Direction of winding
(top view) IN Clockwise ----
EX Clockwise ----
Piston:
Piston to cylinder clearance 0.040 ~ 0.065 mm
(0.0016 ~ 0.0026 in)0.1 mm
(0.004 in)
Piston size “D” 91.945 ~ 91.960 mm
(3.6199 ~ 3.6205 in)----
Measuring point “H” 9 mm (0.354 in) ----
Piston off-set 1 mm (0.0394 in) ----
Piston pin bore inside diameter 18.004 ~ 18.015 mm
(0.7088 ~ 0.7093 in)18.045 mm
(0.7104 in)
Piston pin outside diameter 17.991 ~ 18.000 mm
(0.7083 ~ 0.7087 in)17.971 mm
(0.7075 in) Item Standard Limit
*
H
D