clutch YAMAHA YZ426F 2000 Owners Manual
[x] Cancel search | Manufacturer: YAMAHA, Model Year: 2000, Model line: YZ426F, Model: YAMAHA YZ426F 2000Pages: 608, PDF Size: 45.52 MB
Page 22 of 608
CHAPTER 4
ENGINE
SEAT, FUEL TANK AND
SIDE COVERS
.......................................... 4-1
EXHAUST PIPE AND SILENCER
............ 4-3
RADIATOR
................................................ 4-4
CARBURETOR
......................................... 4-7
CAMSHAFTS
.......................................... 4-17
CYLINDER HEAD
................................... 4-24
VALVES AND VALVE SPRINGS
........... 4-27
CYLINDER AND PISTON
....................... 4-35
CLUTCH
.................................................. 4-41
OIL FILTER, WATER PUMP AND
CRANKCASE COVER (RIGHT)
............. 4-47
BALANCER
............................................ 4-53
OIL PUMP
............................................... 4-56
KICK AXLE AND SHIFT SHAFT
............ 4-60
CDI MAGNETO
....................................... 4-67
ENGINE REMOVAL
................................ 4-71
CRANKCASE AND CRANKSHAFT
....... 4-76
TRANSMISSION, SHIFT CAM,
SHIFT FORK
........................................... 4-85
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
...... 5-1
FRONT BRAKE AND REAR BRAKE
..... 5-10
FRONT FORK
......................................... 5-27
HANDLEBAR
.......................................... 5-40
STEERING
.............................................. 5-45
SWINGARM
............................................ 5-50
REAR SHOCK ABSORBER
................... 5- 57
Page 26 of 608
1 - 1
GEN
INFO
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
Clutch lever
2
Decompression lever
3
Front brake lever
4
Throttle grip
5
Radiator cap
6
Fuel tank cap
7
Oil filler plug/dipstick
8
“ENGINE STOP” button
9
Kick starter
0
Fuel tank
A
Radiator
B
Coolant drain bolt
C
Rear brake pedal
D
Valve joint
E
Fuel cock
F
Cold starter knob
G
Hot starter knob (red)
H
Drive chain
I
Air cleaner
J
Shift pedal
K
Front fork
NOTE:
l
The machine you have purchased may differ
slightly from those shown in the following.
l
Designs and specifications are subject to
change without notice.
1
1
Page 37 of 608
1 - 7
GEN
INFO
SPECIAL TOOLS
YM-33975, 90890-01403 Ring nut wrench
This tool is used when tighten the steering ring nut to
specification.YM-33975 90890-01403
YM-1423, 90890-01423 Damper rod holder
Use this tool to remove and install the damper rod.YM-1423 90890-01423
YM-01442, 90890-01442 Fork seal driver
This tool is used when install the fork oil seal.YM-01442 90890-01442
YU-03112, 90890-03112 Yamaha pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.YU-03112 90890-03112
YU-8036-1
90890-03113Inductive tachometer
Engine tachometer
This tool is needed for observing engine rpm.YU-8036-1 90890-03113
YM-33277-A, 90890-03141 Timing light
This tool is necessary for checking ignition timing.YM-33277-A 90890-03141
YM-04019, 90890-04019
YM-04108, 90890-04108Valve spring compressor
Attachment
This tool needed to remove and install the valve
assemblies.YM-04019
YM-0410890890-04019
90890-04108
YM-91042, 90890-04086 Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.YM-91042 90890-04086
YM-4116, 90890-04116
YM-4097, 90890-04097Valve guide remover
Intake (4.5 mm)
Exhaust (5.0 mm)
This tool is needed to remove and install the valve
guide.YM-4116
YM-409790890-04116
90890-04097
Part number Tool name/How to use Illustration
Page 46 of 608
1 - 9
GEN
INFO
CONTROL FUNCTIONS
EC150000
CONTROL FUNCTIONS
EC151000
“ENGINE STOP” BUTTON
The “ENGINE STOP” button 1 is located on
the left handlebar. Continue pushing the
“ENGINE STOP” button till the engine comes
to a stop.
EC152000
CLUTCH LEVER
The clutch lever 1 is located on the left han-
dlebar; it disengages or engages the clutch.
Pull the clutch lever to the handlebar to disen-
gage the clutch, and release the lever to
engage the clutch. The lever should be pulled
rapidly and released slowly for smooth starts.
EC153000
SHIFT PEDAL
The gear ratios of the constant-mesh 5 speed
transmission are ideally spaced. The gears
can be shifted by using the shift pedal 1 on
the left side of the engine.
EC154000
KICK STARTER
Rotate the kick starter 1 away from the
engine. Push the starter down lightly with your
foot until the gears engage, then kick smoothly
and forcefully to start the engine. This model
has a primary kick starter so the engine can be
started in any gear if the clutch is disengaged.
In normal practices, however, shift to neutral
before starting.
1
Page 71 of 608
SPEC
2 - 2
GENERAL SPECIFICATIONS
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)
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: USA, CDN, ZA,
AUS, NZEUROPE
Primary reduction system Gear
¬
Primary reduction ratio 62/21 (2.952)
¬
Secondary reduction system Chain drive
¬
Secondary reduction ratio 49/14 (3.500) 48/14 (3.429)
Transmission type Constant mesh,
5-speed
¬
Operation Left foot operation
¬
Gear ratio: 1st 24/13 (1.846)
¬
2nd 27/18 (1.500)
¬
3rd 23/18 (1.278)
¬
4th 24/22 (1.091)
¬
5th 20/21 (0.952)
¬
Chassis:
Frame type Semi double cradle
Caster angle 27.8˚
Trail 123 mm (4.84 in)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN, ZA, AUS, NZ
and F)
80/100-21 51R (For EUROPE except F)
Size (rear) 110/90-19 62M (For USA, CDN, ZA, AUS, NZ
and F)
110/90-19 NHS (For EUROPE except F)
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)
2
Page 77 of 608
SPEC
2 - 8
MAINTENANCE SPECIFICATIONS
Clutch:
Friction plate thickness 2.9 ~ 3.1 mm
(0.114 ~ 0.122 in)2.7 mm
(0.11 in)
Quantity 9 ----
Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ----
Quantity 8 ----
Warp limit ---- 0.1 mm
(0.004 in)
Clutch spring free length 44 mm (1.73 in) 43 mm
(1.69 in)
Quantity 6 ----
Clutch housing thrust clearance 0.20 ~ 0.45 mm
(0.0079 ~ 0.0177 in)----
Clutch housing radial clearance 0.010 ~ 0.044 mm
(0.0004 ~ 0.0017 in)----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm
(0.002 in)
Kick starter:
Type Ratchet type ----
Carburetor:
USAEUROPE, CDN,
ZA, AUS, NZ
I. D. mark 5JG1 00 5JG2 10 ----
Main jet (M.J) #162
¬
----
Main air jet (M.A.J) #200
¬
----
Jet needle (J.N) OBEKR-4 OBEKQ-4 ----
Cutaway (C.A) 15
¬
----
Pilot air jet 1 (P.A.J.1) #100
¬
----
Pilot outlet (P.O) 0.9
¬
----
Pilot jet (P.J) #42
¬
----
Pilot screw (example) (P.S) 1-3/4 1-1/2 ----
Bypass 1 (B.P.1) 1.0
¬
----
Valve seat size (V.S) 3.8
¬
----
Starter jet 1 (G.S.1) #72
¬
----
Float height (F.H) 8 mm (0.31 in)
¬
----
Engine idle speed 1,700 ~
1,900 r/min
¬
----
Intake vacuum29.3 ~ 32.0 kPa
(220 ~ 240 mmHg,
8.66 ~ 9.45 inHg)
¬
---- Item Standard Limit
Page 80 of 608
SPEC
2 - 11
MAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Spark plug M10
´
1.0 1 13 1.3 9.4
Camshaft cap M6
´
1.0 10 10 1.0 7.2
Cylinder head (stud bolt) M6
´
1.0 2 7 0.7 5.1
M8
´
1.25 3 15 1.5 11
(bolt) M10
´
1.25 4 44 4.4 32
(nut) M6
´
1.0 2 10 1.0 7.2
M8
´
1.25 2 20 2.0 14
Cylinder head cover M6
´
1.0 2 10 1.0 7.2
Cylinder M6
´
1.0 1 10 1.0 7.2
Timing chain tensioner M6
´
1.0 2 10 1.0 7.2
Tensioner cap bolt M6
´
1.0 1 7 0.7 5.1
Timing chain guide (rear) M6
´
1.0 2 10 1.0 7.2
Decompression shaft M6
´
1.0 1 7 0.7 5.1
Decompression cable guide M6
´
1.0 1 10 1.0 7.2
Exhaust pipe (nut) M8
´
1.25 1 24 2.4 17
(bolt) M8
´
1.25 1 24 2.4 17
Silencer M8
´
1.25 2 35 3.5 25
Silencer clamp M8
´
1.25 1 20 2.0 14
Exhaust pipe protector M6
´
1.0 3 10 1.0 7.2
Clamp (air cleaner joint) M5
´
0.8 1 3 0.3 2.2
Clamp (carburetor joint) M4
´
0.7 1 3 0.3 2.2
Air filter joint clamp M6
´
1.0 1 3 0.3 2.2
Throttle cable cover M5
´
0.8 1 4 0.4 2.9
Air filter element M6
´
1.0 1 2 0.2 1.4
Radiator panel (upper) M6
´
1.0 2 10 1.0 7.2
Radiator M6
´
1.0 6 10 1.0 7.2
Radiator hose clamp M6
´
1.0 8 2 0.2 1.4
Impeller M8 ´ 1.25 1 14 1.4 10
Water pump housing cover M6 ´ 1.0 3 10 1.0 7.2
Coolant drain bolt M6 ´ 1.0 1 10 1.0 7.2
Oil pump cover M5 ´ 0.8 1 4 0.4 2.9
Oil pump M6 ´ 1.0 3 10 1.0 7.2
Engine oil drain bolt (oil filter) M6 ´ 1.0 1 10 1.0 7.2
Oil filter cover M6 ´ 1.0 2 10 1.0 7.2
Oil delivery pipe 1 M10 ´ 1.25 1 20 2.0 14
M8 ´ 1.25 2 18 1.8 13
Oil hose clamp – 2 2 0.2 1.4
Clutch cover M6 ´ 1.0 7 10 1.0 7.2
Crankcase cover (right) M6 ´ 1.0 10 10 1.0 7.2
Crankcase cover (left) M6 ´ 1.0 8 10 1.0 7.2
Crankcase M6 ´ 1.0 12 12 1.2 8.7
Oil drain bolt (crankcase) M12 ´ 1.5 1 20 2.0 1.4
Oil drain bolt (frame) M8 ´ 1.25 1 23 2.3 17
Page 81 of 608
SPEC
2 - 12
MAINTENANCE SPECIFICATIONS
Oil strainer (frame) M18 ´ 1.5 1 90 9.0 65
Crankcase bearing stopper M6 ´ 1.0 15 10 1.0 7.2
Drive axle oil seal stopper M6 ´ 1.0 2 10 1.0 7.2
Ratchet wheel guide M6 ´ 1.0 2 12 1.2 8.7
Kick crank M8 ´ 1.25 1 33 3.3 24
Primary drive gear M20 ´ 1.0 1 75 7.5 54
Clutch boss M20 ´ 1.0 1 75 7.5 54
Clutch spring M6 ´ 1.0 6 8 0.8 5.8
Balancer driven gear M14 ´ 1.0 1 50 5.0 36
Balancer weight plate M6 ´ 1.0 3 10 1.0 7.2
Drive sprocket M20 ´ 1.0 1 75 7.5 54
Shift guide M6 ´ 1.0 2 10 1.0 7.2
Stopper lever M6 ´ 1.0 1 10 1.0 7.2
Segment M8 ´ 1.25 1 30 3.0 22
Neutral switch M5 ´ 0.8 2 4 0.4 2.9 Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Page 83 of 608
SPEC
2 - 14
MAINTENANCE SPECIFICATIONS
Wheel:
Front wheel type Spoke wheel ----
Rear wheel type Spoke wheel ----
Front rim size/material 21 ´ 1.60/Aluminum ----
Rear rim size/material 19 ´ 2.15/Aluminum ----
Rim runout limit:
Radial ---- 2.0 mm (0.08 in)
Lateral ---- 2.0 mm (0.08 in)
Drive chain:
Type/manufacturer 520DM-DHA/DAIDO ----
Number of links 113 links + joint ----
Chain slack 40 ~ 50 mm (1.6 ~ 2.0 in) ----
Chain length (10 links) ----152.5 mm (6.00 in)
Front disc brake:
Disc outside dia. ´ Thickness 245 ´ 3.0 mm (9.65 ´ 0.12 in) 245 ´ 2.5 mm
(9.65 ´ 0.08 in)
Deflection limit ----0.15 mm (0.006 in)
Pad thickness 4.4 mm (0.17 in) 1 mm (0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 27.0 mm (1.063 in) ´ 2 ----
Brake fluid type DOT #4 ----
Rear disc brake:
Disc outside dia. ´ Thickness 240 ´ 4.0 mm (9.45 ´ 0.16 in) 240 ´ 3.5 mm
(9.45 ´ 0.14 in)
Deflection limit ----0.15 mm (0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 12.7 mm (0.500 in) ----
Caliper cylinder inside dia. 27.0 mm (1.063 in) ´ 1 ----
Brake fluid type DOT #4 ----
Brake lever and brake pedal:
Brake lever position 82.5 mm (3.25 in) ----
Brake pedal height
(vertical height below footrest top)5 mm (0.20 in) ----
Clutch lever free play (at lever pivot) 2 ~ 4 mm (0.08 ~ 0.16 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit
Page 84 of 608
SPEC
2 - 15
MAINTENANCE SPECIFICATIONS
NOTE:
1. First, tighten the ring nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the ring nut
wrench, then loosen the ring nut one turn.
2. Retighten the ring nut 7 Nm (0.7 m • kg, 5.1 ft • lb).Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Handle crown and outer tube M8 ´ 1.25 4 23 2.3 17
Under bracket and outer tube M8 ´ 1.25 4 20 2.0 14
Handle crown and steering shaft M24 ´ 1.0 1 145 14.5 105
Handlebar holder (upper) M8 ´ 1.25 4 23 2.3 17
Steering ring nut M28 ´ 1.0 1 Refer to NOTE.
Front fork and cap bolt M48 ´ 1.0 2 30 3.0 22
Front fork and base valve M30 ´ 1.0 2 55 5.5 40
Cap bolt and damper rod (front fork) M12 ´ 1.25 2 29 2.9 21
Bleed screw (front fork) and cap bolt M5 ´ 0.8 2 1 0.1 0.7
Front fork and protector M6 ´ 1.0 6 10 1.0 7.2
Front fork and brake hose holder M6 ´ 1.0 2 10 1.0 7.2
Front fork and hose cover M8 ´ 1.25 1 16 1.6 11
Front fork and hose cover M6 ´ 1.0 1 7 0.7 5.1
Throttle cable cap M5 ´ 0.8 2 4 0.4 2.9
Clutch lever holder M5 ´ 0.8 2 4 0.4 2.9
Decompression lever holder M5 ´ 0.8 2 4 0.4 2.9
Front brake master cylinder and bracket M6 ´ 1.0 2 9 0.9 6.5
Front brake master cylinder cap M4 ´ 0.7 2 2 0.2 1.4
Brake lever mounting (bolt) M6 ´ 1.0 1 7 0.7 5.1
Brake lever mounting (nut) M6 ´ 1.0 1 7 0.7 5.1
Brake lever position locknut M6 ´ 1.0 2 7 0.7 5.1
Cable guide (front brake hose) and guide stay M5 ´ 0.8 1 4 0.4 2.9
Front brake hose union bolt (master cylinder)M10 ´ 1.25 1 30 3.0 22
Front brake hose union bolt (caliper) M10 ´ 1.25 1 30 3.0 22
Front brake caliper and front fork M8 ´ 1.25 2 23 2.3 17
Brake caliper (front and rear) and pad pin plugM10 ´ 1.0 1 3 0.3 2.2
Front brake caliper and pad pin M10 ´ 1.0 1 18 1.8 13
Rear brake caliper and pad pin M10 ´ 1.0 1 18 1.8 13
Brake caliper (front and rear) and bleed screw M8 ´ 1.25 1 6 0.6 4.3
Front wheel axle and nut M16 ´ 1.5 1 105 10.5 75
Front wheel axle holder M8 ´ 1.25 4 23 2.3 17
Front brake disc and wheel hub M6 ´ 1.0 6 12 1.2 8.7
Rear brake disc and wheel hub M6 ´ 1.0 6 14 1.4 10
Brake pedal mounting M8 ´ 1.25 1 19 1.9 13
Rear brake master cylinder and frame M6 ´ 1.0 2 10 1.0 7.2