CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION ...........................................1-1
MACHINE IDENTIFICATION .....................1-2
IMPORTANT INFORMATION ....................1-3
CHECKING OF CONNECTION .................1-5
SPECIAL TOOLS ......................................1-6
CONTROL FUNCTIONS ............................1-9
FUEL ........................................................1-12
STARTING AND OPERATION ................1-13
CLEANING AND STORAGE ...................1-14
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS ...................2-1
MAINTENANCE SPECIFICATIONS ..........2-4
GENERAL TORQUE
SPECIFICATIONS ...................................2-17
DEFINITION OF UNITS ...........................2-17
CABLE ROUTING DIAGRAM .................2-18
CHAPTER 3
REGULAR INSPECTION AND
ADJUSTMENTS
MAINTENANCE INTERVALS ...................3-1
PRE-OPERATION INSPECTION AND
MAINTENANCE .........................................3-3
ENGINE ......................................................3-4
CHASSIS .................................................3-12
ELECTRICAL ...........................................3-23
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 10 1.0 7.2
Drive sprocket cover M6 × 1.0 2 7 0.7 5.1
Crankcase cover (right) M6 × 1.0 9 10 1.0 7.2
Timing plug M14 ×
1.5 1 7 0.7 5.1
Crankshaft end cover M32 ×
1.5 1 7 0.7 5.1
Kick crank M6 ×
1.0 1 10 1.0 7.2
Starter clutch and rotor (TT-R90E) M6 ×
1.0 3 14 1.4 10
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 70 7.0 50
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
Neutral switch (TT-R90E) M10 × 1.25 1 18 1.8 13
MAINTENANCE SPECIFICATIONS
SPEC
2 - 13
NOTE:
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).
-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 48 4.8 35
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)(TT-R90) M6 × 1.0 4 13 1.3 9.4
(TT-R90E) M8 × 1.25 4 23 2.3 17
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
Brake lever mounting (bolt) M6 × 1.0 1 3 0.3 2.2
Brake lever mounting (nut) M6 × 1.0 1 4 0.4 2.9
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
Drive chain guard M5 × 0.8 2 4 0.4 2.9
Drive chain support M5 × 0.8 3 4 0.4 2.9
Chain puller locknut M6 × 1.0 2 7 0.7 5.1
Footrest and frame M8 × 1.25 2 30 3.0 22
Battery box (TT-R90E) M6 × 1.0 3 5 0.5 3.6
MAINTENANCE SPECIFICATIONS
SPEC
2 - 17
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
EC230000
DEFINITION OF UNITS
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
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
2Pressure
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
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
3 - 19
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Ring nut wrench:
YU-1268/90890-01268
Tighten the ring nut 4 using ring nut
wrench 5 and turn the steering right and
left a few times.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YM-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m kg, 27 ft lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
1 Nm (0.1 m kg, 0.7 ft lb)
Check the steering shaft by turning it lock
to lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
Install the handle crown 6, handlebar 7,
and front fender.
CAUTION:
Install the handlebar holder with its
groove
a facing outward, and tighten
the bolts so that the gaps
b are equal.
T R..
Steering stem bolt:
40 Nm (4.0 m kg, 2.9 ft lb)
Front fork cap bolt:
40 Nm (4.0 m kg, 2.9 ft lb)
Handlebar upper holder:
13 Nm (1.3 m kg, 9.4 ft lb)
5
4
2 3
a
bb
3 - 20
INSP
ADJ
TT-R90E
Steering ring nut
Steering ring nut adjustment steps:
Remove the front fender 1.
Remove the handlebar and handle crown.
Loosen the ring nut 2 using the ring nut
wrench 3.
Ring nut wrench:
YU-1268/90890-01268
Tighten the ring nut 4 using ring nut
wrench 5 and turn the steering right and
left a few times.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YM-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m kg, 27 ft lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
1 Nm (0.1 m kg, 0.7 ft lb)
Check the steering shaft by turning it lock
to lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
Install the handle crown 6, main switch
7, handlebar 8, and front fender.
2 3
5
4
8
7
6
STEERING HEAD INSPECTION AND ADJUSTMENT
4 - 12
ENGCYLINDER HEAD
CAUTION:
.Do not turn the crankshaft during instal-
lation of the camshaft. Damage or
improper valve timing will result.
Remove the safety wire from the timing
chain.
4. Install:
Washer
Bolt 1
NOTE:
Install the bolt 1 while holding the rotor nut
with a wrench.
T R..20 Nm (2.0 m · kg, 14 ft · lb)
5. Install:
Timing chain tensioner
6. Check:
Rotor “I” mark
Align with the crankcase stationary
pointer.
Valve clearance
Out of specification → Adjust.
Refer to the “VALVE CLEARANCE
ADJUSTMENT” section in CHAPTER 3. Installation steps:
Remove the tensioner cap bolt 1 and
spring 2.
Release the timing chain tensioner one-
way cam 3 and push the tensioner rod 4
all the way in.
Install the tensioner with a new gasket 5
onto the cylinder.
T R..
Timing chain tensioner bolt:
10 Nm (1.0 m kg, 7.2 ft lb)
Install the spring 2 and cap bolt 1.
Tighten the bolt (with gasket) to the speci-
fied torque.
T R..
Cap bolt:
8 Nm (0.8 m kg, 5.8 ft lb)