YAMAHA TTR90 2001 Repair Manual
Manufacturer: YAMAHA, Model Year: 2001, Model line: TTR90, Model: YAMAHA TTR90 2001Pages: 288, PDF Size: 15.39 MB
Page 61 of 288

SPEC
2 - 6
Stem runout limit ---- 0.02 mm
(0.0008 in)
Valve 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)
Valve spring:
Free length IN 28.32 mm (1.11 in) 26.9 mm
(1.06 in)
EX 28.32 mm (1.11 in) 26.9 mm
(1.06 in)
Set length (valve closed) IN 24.2 mm (0.95 in) ----
EX 24.2 mm (0.95 in) ----
Compressed pressure
(installed) IN 90.4 ~ 104.1 N
(9.2 ~ 10.6 kg, 20.32 ~ 23.40 lb)----
EX 90.4 ~ 104.1 N
(9.2 ~ 10.6 kg, 20.32 ~ 23.40 lb)----
Tilt limit IN ---- 2.5˚/1.2 mm
(2.5˚/0.05 in)
EX ---- 2.5˚/1.2 mm
(2.5˚/0.05 in)
Direction of winding
(top view) IN Clockwise ----
EX Clockwise ---- Item Standard Limit
*
MAINTENANCE SPECIFICATIONS
Page 62 of 288

SPEC
2 - 7
Piston:
Piston to cylinder clearance 0.025 ~ 0.045 mm
(0.0010 ~ 0.0018 in)0.15 mm
(0.0059 in)
Piston size “D” 46.960 ~ 46.975 mm
(1.8488 ~ 1.8494 in)----
Piston over size (2nd) 47.5 mm (1.8701 in) ----
(4th) 48.0 mm (1.8898 in) ----
Measuring point “H” 4 mm (0.16 in) ----
Piston off-set 0.75 mm (0.0295 in) ----
Piston pin bore inside diameter 13.002 ~ 13.013 mm
(0.5119 ~ 0.5123 in)13.045 mm
(0.5136 in)
Piston pin outside diameter 12.996 ~ 13.000 mm
(0.5117 ~ 0.5118 in)12.976 mm
(0.5109 in)
Piston rings:
Top ring
Type Barrel ----
Dimensions (B
´
T) 1.0
´
2.0 mm (0.04
´
0.08 in) ----
End gap (installed) 0.10 ~ 0.25 mm
(0.004 ~ 0.010 in)0.4 mm
(0.016 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) 1.0
´
2.0 mm (0.04
´
0.08 in) ----
End gap (installed) 0.10 ~ 0.25 mm
(0.004 ~ 0.010 in)0.4 mm
(0.016 in)
Side clearance 0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)0.12 mm
(0.005 in)
Oil ring
Dimensions (B
´
T) 2.0
´
2.3 mm (0.08
´
0.09 in) ----
End gap (installed) 0.2 ~ 0.7 mm (0.01 ~ 0.03 in) ----Item Standard Limit
H
D
T
B
B
T
B
T
MAINTENANCE SPECIFICATIONS
Page 63 of 288

SPEC
2 - 8
Crankshaft:
Crank width “A” 42.95 ~ 43.00 mm
(1.691 ~ 1.693 in)----
Runout limit C ---- 0.03 mm
(0.0012 in)
Big end side clearance “D” 0.10 ~ 0.40 mm
(0.0039 ~ 0.0157 in)0.50 mm
(0.02 in)
Big end radial clearance “E” 0.010 ~ 0.025 mm
(0.0004 ~ 0.0010 in)0.05 mm
(0.002 in)
Clutch:
Friction plate thickness 2.7 ~ 2.9 mm
(0.106 ~ 0.114 in)2.6 mm
(0.102 in)
Quantity 5 ----
Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ----
Quantity 4 ----
Warp limit ---- 0.2 mm
(0.008 in)
Clutch spring free length 26.2 mm (1.03 in) 24.2 mm
(0.95 in)
Quantity 4 ----
Clutch release method Inner push, cam push ----
Push rod bending limit ---- 0.5 mm
(0.02 in)
Automatic centrifugal clutch: ----
Clutch-in revolution 2,160 ~ 2,560 r/min ----
Clutch-stall revolution 3,300 ~ 3,800 r/min
Shifter:
Shifter type Cam drum and guide bar ----
Kick starter:
Type Ratchet type ----
Kick clip friction force 5.8 ~ 14.7 N
(0.59 ~ 1.50 kg, 1.3 ~ 3.3 lb)
Carburetor:
I. D. mark 5HN1 01 ----
Main jet (M.J) #90 ----
Main air jet (M.A.J) ø 1.1 ----
Jet needle (J.N) 4E9-2 ----
Cutaway (C.A) 2.5 ----
Pilot outlet (P.O) ø 1.0
´
2.0 ----
Pilot jet (P.J) #12.5 ----
Valve seat size (V.S) ø 1.5 ----
Starter jet 1 (G.S.1) #37.5 ----
Pilot air screw 1-3/4 turns out
Float height (F.H) 15.5 ~ 16.5 mm (0.61 ~ 0.65 in) ----
Fuel level (F.L) 2 ~ 3 mm (0.08 ~ 0.1 in) ----
Engine idle speed 1,400 ~ 1,600 r/min ----Item Standard Limit
MAINTENANCE SPECIFICATIONS
CC
D
A
E
Page 64 of 288

SPEC
2 - 9
Lubrication system:
Oil filter type Wire mesh type ----
Oil pump type Trochoid type ----
Tip clearance “A” or “B” 0.15 mm
(0.0059 in)0.2 mm
(0.0079 in)
Side clearance 0.13 ~ 0.18 mm
(0.0051 ~ 0.0071 in)0.23 mm
(0.0091 in)
Housing and rotor clearance 0.06 ~ 0.10 mm
(0.0024 ~ 0.0039 in)0.15 mm
(0.0059 in) Item Standard Limit
MAINTENANCE SPECIFICATIONS
Page 65 of 288

SPEC
2 - 10
Part to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
Cylinder head nut M8
´
1.25 4 22 2.2 16
Cylinder head bolt M6
´
1.0 2 10 1.0 7.2
Spark plug M10
´
1.0 1 13 1.3 9.4
Camshaft sprocket cover bolt M6
´
1.0 2 7 0.7 5.1
Tappet cover M45
´
1.5 2 18 1.8 13
Exhaust pipe stud bolt M6
´
1.0 2 7 0.7 5.1
Rotor nut M12
´
1.25 1 48 4.8 35
Timing chain guide (rear) M6
´
1.0 2 10 1.0 7.2
Valve clearance adjust screw locknut M5
´
0.5 2 7 0.7 5.1
Camshaft sprocket M8
´
1.25 1 20 2.0 14
Camshaft bearing retainer M6
´
1.0 1 10 1.0 7.2
Timing chain tensioner cap bolt M8
´
1.25 1 8 0.8 5.8
Timing chain tensioner M6
´
1.0 2 10 1.0 7.2
Oil pump M6
´
1.0 2 7 0.7 5.1
Drain bolt M12
´
1.5 1 20 2.0 14
Carburetor joint (cylinder head side) M6
´
1.0 2 7 0.7 5.1
Carburetor joint (carburetor side) M6
´
1.0 2 7 0.7 5.1
Air filter case M6
´
1.0 2 7 0.7 5.1
Exhaust pipe M6
´
1.0 2 7 0.7 5.1
Exhaust pipe protector M6
´
1.0 7 7 0.7 5.1
Silencer M8
´
1.25 1 24 2.4 17
Silencer protector M5
´
0.8 2 4 0.4 2.9
Crankcase M6
´
1.0 9 10 1.0 7.2
Crankcase cover (left) M6
´
1.0 8 7 0.7 5.1
Drive sprocket cover M6
´
1.0 2 7 0.7 5.1
Crankcase cover (right) M6
´
1.0 9 7 0.7 5.1
Timing plug M14
´
1.5 1 7 0.7 5.1
Crankshaft end cover M32
´
1.5 1 7 0.7 5.1
Cylinder head stud bolt M8
´
1.25 4 13 1.3 9.4
Kick crank M6
´
1.0 1 10 1.0 7.2
Primary drive gear M12
´
1.0 1 50 5.0 36
Pressure plate M5
´
0.8 4 6 0.6 4.3
Clutch boss M14
´
1.0 1 60 6.0 43
Main axle bearing retainer M6
´
1.0 1 10 1.0 7.2
Shift pedal M6
´
1.0 1 8 0.8 5.8
Clutch adjust screw locknut M6
´
1.0 1 8 0.8 5.8
Pickup coil M6
´
1.0 2 10 1.0 7.2
Stator assembly M6
´
1.0 3 10 1.0 7.2
MAINTENANCE SPECIFICATIONS
Page 66 of 288

SPEC
2 - 11
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Angular bearing ----
Front suspension:
Front fork travel 110 mm (4.33 in) ----
Fork spring free length 425.1 mm (16.74 in) 417 mm (16.4 in)
Fork spring fitting length 415.1 mm (16.34 in) ----
Spring rate, STD K = 3.4 N/mm
(0.35 kg/mm, 19.41 lb/in)----
Optional spring/spacer No ----
Oil capacity 64 cm
3
(2.26 lmp oz, 2.16 US oz) ----
Oil level 185 mm (7.28 in) ----
Oil grade Fork oil 15W or equivalent ----
Rear suspension:
Shock absorber travel 48 mm (1.89 in) ----
Spring free length 169 mm (6.65 in) ----
Fitting length 165 mm (6.5 in) ----
Spring rate, STD K = 45.6 N/mm
(4.65 kg/mm, 260 lb/in)----
Optional spring No ----
Enclosed gas pressure 2,000 kPa
(20 kg/cm
2
, 290 psi)----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)
Side clearance ---- 0.3 mm (0.01 in)
Wheel:
Front wheel type Spoke wheel ----
Rear wheel type Spoke wheel ----
Front rim size/material 14
´
1.40/steel ----
Rear rim size/material 12
´
1.60/steel ----
Rim runout limit:
Radial ---- 2.0 mm (0.08 in)
Lateral ---- 2.0 mm (0.08 in)
Drive chain:
Type/manufacturer DID420(I)/DAIDO ----
Number of links 86 links ----
Chain slack 40 ~ 53 mm (1.6 ~ 2.1 in) ----
Chain length (10 links) ---- 121.9 mm
(4.80 in)
MAINTENANCE SPECIFICATIONS
Page 67 of 288

SPEC
2 - 12
Drum brake:
Front drum brake type Leading, trailing ----
Rear drum brake type Leading, trailing ----
Front drum inside diameter 95 mm (3.74 in) 96 mm (3.78 in)
Rear drum inside diameter 110 mm (4.33 in) 111 mm (4.37 in)
Front lining thickness 3 mm (0.12 in) 2 mm (0.08 in)
Rear lining thickness 4 mm (0.16 in) 2 mm (0.08 in)
Front shoe spring free length 32.7 mm (1.29 in) ----
Rear shoe spring free length 50.5 mm (1.99 in) ----
Brake lever and brake pedal:
Brake lever free play (lever end) 10 ~ 20 mm (0.39 ~ 0.79 in) ----
Brake pedal free play 10 ~ 20 mm (0.39 ~ 0.79 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit
MAINTENANCE SPECIFICATIONS
Page 68 of 288

SPEC
2 - 13
NOTE:
l
1. First, tighten the ring nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the ring nut
wrench and turn the steering right and left a few times; then loosen the ring nut one turn.
2. Retighten the ring nut 1 Nm (0.1 m • kg, 0.7 ft • lb).
l
-marked portion shall be checked for torque tightening after break-in or before each ride.Part to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
Engine mounting:
Engine and frame (front-upper) M8
´
1.25 1 30 3.0 22
Engine and frame (rear-upper) M8
´
1.25 1 26 2.6 19
Engine and frame (rear-lower) M10
´
1.25 1 40 4.0 29
Starter cable and frame M11
´
1.25 1 1 0.1 0.7
Pivot shaft and nut M10
´
1.25 1 30 3.0 22
Handle crown and steering shaft M10
´
1.25 1 40 4.0 29
Front fork cap bolt M20
´
1.0 2 40 4.0 29
Under bracket and front fork M10
´
1.25 2 33 3.3 24
Damper rod bolt M8
´
1.25 2 20 2.0 14
Handle crown and handlebar holder (lower) M10
´
1.25 2 40 4.0 29
Handlebar holder (upper) M6
´
1.0 4 13 1.3 9.4
Front brake cable holder and front fork M6
´
1.0 2 7 0.7 5.1
Steering ring nut M25 1 Refer to NOTE.
Fuel tank and fuel cock M6
´
1.0 2 7 0.7 5.1
Fuel tank and frame M6
´
1.0 2 7 0.7 5.1
Grab bar and frame M6
´
1.0 4 13 1.3 9.4
Front brake camshaft lever and camshaft M6
´
1.0 1 7 0.7 5.1
Rear brake camshaft lever and camshaft M6
´
1.0 1 7 0.7 5.1
Front wheel axle nut M10
´
1.25 1 35 3.5 25
Rear brake shoe plate tension bar M8
´
1.25 2 26 2.6 19
Wheel drive hub and driven sprocket M8
´
1.25 4 25 2.5 18
Rear wheel axle nut M12
´
1.25 1 60 6.0 43
Wheel nipple (spoke) — 64 2 0.2 1.4
Chain case M5
´
0.8 5 4 0.4 2.9
Chain puller locknut M6
´
1.0 2 3 0.3 2.2
Footrest and frame M8
´
1.25 2 30 3.0 22
MAINTENANCE SPECIFICATIONS
Page 69 of 288

SPEC
2 - 14
EC212300
ELECTRICAL
Item Standard Limit
CDI:
Magneto-model/manufacturer F5HN 00/YAMAHA ----
Source coil resistance (color) 688 ~ 1,032
W
at 20 ˚C (68 ˚F)
(Brown – Green)----
Pickup coil resistance (color) 248 ~ 372
W
at 20 ˚C (68 ˚F)
(Red – White)----
CDI unit-model/manufacturer 4GL-20/YAMAHA ----
Ignition coil:
Model/manufacturer 4KJ-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary winding resistance 0.18 ~ 0.28
W
at 20 ˚C (68 ˚F) ----
Secondary winding resistance 6.3 ~ 9.5 k
W
at 20 ˚C (68 ˚F) ----
Spark plug cap:
Type Resin ----
Resistance 10 k
W
at 20 ˚C (68 ˚F) ----
MAINTENANCE SPECIFICATIONS
Page 70 of 288

2 - 15
SPEC
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
EC220001
GENERAL TORQUE
SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
EC230000
DEFINITION OF UNITS
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3
meter
10
-2
meterLength
Length
kg kilogram 10
3
gram Weight
N Newton 1 kg
´
m/sec
2
Force
Nm
m • kgNewton meter
Meter kilogramN
´
m
m
´
kgTorque
Torque
Pa Pascal N/m
2
Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3
Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute — Engine speed