Sym HD2 125 User manual

HD2 125 / 200
SERVICE MANUAL
20110209
Foreword
How to Use This Manual
Contents
Mechanism Illustration

FOREWORD
This service manual contains the technical data of each component inspection and
repair for the SANYANG HD2 125 / 200 motorcycles. The manual is shown with
illustrations and focused on “Service Procedures”, “Operation Key Points”, and
“Inspection Adjustment” so that provides technician with service guidelines.
If the style and construction of the motorcycle, HD2 125 / 200 is different from that
of the photos, pictures shown in this manual, the actual vehicle shall prevail.
Specifications are subject to change without notice.
Service Department
SANYANG INDUSTRY CO., LTD.
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HOW TO USE THIS MANUAL
This service manual describes basic information of different system parts and
system inspection & service for SANYANG HD2 125 / 200 motorcycles. In addition,
please refer to the manual contents in detailed for the model you serviced in
inspection and adjustment.
The first chapter covers general information and trouble diagnosis.
The second chapter covers service maintenance information and special tools
manual.
The third to the 12th chapters cover engine and driving systems.
The 13th chapter is cooling system.
The 14th to the 17th chapter is contained the parts set of assembly frame body.
The 18th chapter is electrical equipment.
The 19th chapter is wiring diagram.
Please see index of content for quick having the special parts and system
information.
There are 4 buttons, “Foreword”, “Contents”, “How to use this manual” and
“Mechanism Illustrations” on the PDF version, and can be access to these items by
click the mouse.
If user wants to look for the content of each chapter, selecting the words of each
chapter on the contents can reach to each chapter. There are two buttons,
“Homepage and contents, onto the top line of first page of the each chapter. Thus,
if the user needs to check other chapters, he can click the top buttons to back the
homepage or contents. The content of each chapter can be selected too.
Therefore, when needs to checking the content inside of the chapter, click the
content words of the chapter so that can back to the initial section of the content.
In addition, there is a “To this chapter contents” button at the second page of each
content so that clicking the button can back to the contents of this chapter.
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CONTENTS
Page Content Index
1-1 ~ 1-24 GENERAL INFORMATION
1
2-1 ~ 2-14 MAINTENANCE INFORMATION
2
3-1 ~ 3-8 LUBRICATION SYSTEM 3
4-1 ~ 4-12 FUEL SYSTEM 4
5-1 ~ 5-60 FUEL INJECTION SYSTEM 5
6-1 ~ 6-8 ENGINE REMOVAL 6
7-1 ~ 7-14 CYLINDER HEAD / VALVE 7
8-1 ~ 8-8 CYLINDER / PISTON 8
9-1 ~ 9-14 V-BELT DRIVING SYSTEM 9
10-1 ~ 10-10 FINAL DRIVE MECHANISM 10
11-1 ~ 11-8 AC. GENERATOR / START CLUTCH 11
12-1 ~ 12-8 CRANKCASE / CRANKSHAFT 12
13-1 ~ 13-14 COOLING SYSTEM 13
14-1 ~ 14-16 BODY COVER 14
15-1 ~ 15-12 BRAKE SYSTEM 15
16-1 ~ 16-10 STEERING / FRONT WHEEL / FRONT CUSHION 16
17-1 ~ 17-6 REAR WHEEL / REAR FORK / REAR CUSHION 17
18-1 ~ 18-20 ELECTRICAL SYSTEM 18
19-1 ~ 19-2 WIRING DIAGRAM
19
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MECHANISM ILLUSTRATIONS
HD2 125 / 200
Winker relay
Radiator
Spark plug
Engine number
Engine oil drain bolt
Reserve tank cap
Radiator filler cap
Ignition coil
Horn Fuel unit
Tail light/
Rear winker light
Fuel tank cap
Battery/CDI
Exhaust muffler
Oil lever / Oil filter
Water pump
AC. Generator
Rear brake lever
Front brake lever
Winker light / Horn /
Dimmer & Passing
switches Headlight/Start switches
Main switch
Gear oil drain bolt
Air cleaner
Luggage box
Front winker light
Headlight
Fuse box /
Regulator rectifier
Starter relay
Headlight relay
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1. GENERAL INFORMATION
1-1
Symbols and Marks..............................1-1
General Safety......................................1-2
Service Precautions.............................1-3
Specifications.......................................1-9
Torque Values ......................................1-13
Troubleshooting-Carburetor Model....1-15
Troubleshooting-EFi Model.................1-19
Lubrication Points................................1-23
Symbols and Marks
Symbols and marks are used in this manual to indicate what and where the special service are needed, in
case supplemental information is procedures needed for these symbols and marks, explanations will be
added to the text instead of using the symbols or marks.
Warning Means that serious injury or even death may result if procedures are not
followed.
Caution Means that equipment damages may result if procedures are not followed.
Engine oil
Limits to use SAE 10W-30 API SG class oil. Warranty will not cover the
damage that caused by not apply with the limited engine oil.
(Recommended oil: KING MATE G-3 oil)
Grease King Mate G-3 is recommended.
Gear oil
King Mate gear oil serials are recommended. (Bramax HYPOID GEAR OIL
# 140)
Locking sealant
Apply sealant, medium strength sealant should be used unless otherwise
specified.
Oil seal Apply with lubricant.。
Renew Replace with a new part before installation.
Brake fluid Use recommended brake fluid DOT3 or WELLRUN brake fluid.
Special tools Special tools
Correct Meaning correct installation.
Wrong Meaning wrong installation.
Indication Indication of components.
Directions Indicates position and operation directions
Components assembly directions each other.
Indicates where the bolt installation direction, --- means that bolt cross
through the component (invisibility).
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1

1. GENERAL INFORMATION
1-2
General safety
Carbon monoxide
If you must run your engine, ensure the place is
well ventilated. Never run your engine in a closed
area. Run your engine in an open area, if you
have to run your engine in a closed area, be sure
to use an extractor.
Caution
Exhaust contains toxic gas which may cause one
to lose consciousness and even result in death.
Gasoline
Gasoline is a low ignition point and explosive
material. Work in a well-ventilated place, no flame
or spark should be allowed in the work place or
where gasoline is being stored.
Caution
Gasoline is highly flammable, and may explode
under some conditions, keep it away from
children.
Used engine oil
Caution
Prolonged contact with used engine oil (or
transmission oil) may cause skin cancer although
it might not be verified.
We recommend that you wash your hands with
soap and water right after contacting. Keep the
used oil beyond reach of children.
Hot components
Caution
Components of the engine and exhaust system
can become extremely hot after engine running.
They remain very hot even after the engine has
been stopped for some time. When performing
service work on these parts, wear insulated
gloves and wait until cooling off.
Battery
Caution
‧ Battery emits explosive gases; flame is strictly
prohibited. Keep the space well ventilated
when charging the battery.
‧ Battery contains sulfuric acid (electrolyte)
which can cause serious burns so be careful
do not be spray on your eyes or skin. If you
get battery acid on your skin, flush it off
immediately with water. If you get battery acid
in your eyes, flush it off immediately with
water and then go to hospital to see an
ophthalmologist.
‧ If you swallow it by mistake, drink a lot of
water or milk, and take some laxative such as
castor oil or vegetable oil and then go to see a
doctor.
‧ Keep electrolyte beyond reach of children.
Brake shoe
Do not use an air hose or a dry brush to clean
components of the brake system, use a vacuum
cleaner or the equivalent to avoid dust flying.
Caution
Inhaling brake shoe or pad ash may cause
disorders and cancer of the breathing system
Brake fluid
Caution
Spilling brake fluid on painted, plastic, or rubber
parts may cause damage to the parts. Place a
clean towel on the above-mentioned parts for
protection when servicing the brake system.
Keep the brake fluid beyond reach of children.
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1. GENERAL INFORMATION
1-3
Service Precautions
yAlways use with Sanyang genuine parts and
recommended oils. Using non-designed parts
for Sanyang motorcycle may damage the
motorcycle.
ySpecial tools are designed for remove and
install of components without damaging the
parts being worked on. Using wrong tools may
result in parts damaged.
yWhen servicing this motorcycle, use only metric
tools. Metric bolts, nuts, and screws are not
interchangeable with the English system, using
wrong tools and fasteners may damage this
vehicle.
yClean the outside of the parts or the cover
before removing it from the motorcycle.
Otherwise, dirt and deposit accumulated on the
part's surface may fall into the engine, chassis,
or brake system to cause a damage.
yWash and clean parts with high ignition point
solvent, and blow dry with compressed air. Pay
special attention to O-rings or oil seals because
most cleaning agents have an adverse effect on
them.
yNever bend or twist a control cable to prevent
unsmooth control and premature worn out.
yRubber parts may become deteriorated when
old, and prone to be damaged by solvent and oil.
Check these parts before installation to make
sure that they are in good condition, replace if
necessary.
yWhen loosening a component which has
different sized fasteners, operate with a
diagonal pattern and work from inside out.
Loosen the small fasteners first. If the bigger
ones are loosen first, small fasteners may
receive too much stress.
yStore complex components such as
transmission parts in the proper assemble order
and tie them together with a wire for ease of
installation later.
yNote the reassemble position of the important
components before disassembling them to
ensure they will be reassembled in correct
dimensions (depth, distance or position).
yComponents not to be reused should be
replaced when disassembled including gaskets
metal seal rings, O-rings, oil seals, snap rings,
and split pins.
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1. GENERAL INFORMATION
1-4
yThe length of bolts and screws for assemblies,
cover plates or boxes is different from one
another, be sure they are correctly installed. In
case of confusion, Insert the bolt into the hole to
compare its length with other bolts, if its length
out side the hole is the same with other bolts, it
is a correct bolt. Bolts for the same assembly
should have the same length.
yTighten assemblies with different dimension
fasteners as follows: Tighten all the fasteners
with fingers, then tighten the big ones with
special tool first diagonally from inside toward
outside, important components should be
tightened 2 to 3 times with appropriate
increments to avoid warp unless otherwise
indicated. Bolts and fasteners should be kept
clean and dry. Do not apply oil to the threads.
yWhen oil seal is installed, fill the groove with
grease, install the oil seal with the name of the
manufacturer facing outside, check the shaft on
which the oil seal is to be installed for
smoothness and for burrs that may damage the
oil seal.
yRemove residues of the old gasket or sealant
before reinstallation, grind with a grindstone if
the contact surface has any damage.
yThe ends of rubber hoses (for fuel, vacuum, or
coolant) should be pushed as far as they can go
to their connections so that there is enough
room below the enlarged ends for tightening the
clamps.
yRubber and plastic boots should be properly
reinstalled to the original correct positions as
designed.
yThe tool should be pressed against two (inner
and outer) bearing races when removing a ball
bearing. Damage may result if the tool is
pressed against only one race (either inner race
or outer race). In this case, the bearing should
be replaced. To avoid damaging the bearing,
use equal force on both races.
Both of these examples can result in
bearing damage.
Manufacturer's name
Groove
Clamp
Connector
Boots
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1. GENERAL INFORMATION
1-5
yLubricate the rotation face with specified
lubricant on the lubrication points before
assembling.
yCheck if positions and operation for installed
parts is in correct and properly.
yMake sure service safety each other when
conducting by two persons.
yNote that do not let parts fall down.
yBefore battery removal operation, it has to
remove the battery negative (-) cable firstly.
Notre tools like open-end wrench do not contact
with body to prevent from circuit short and
create spark.
yAfter service completed, make sure all
connection points is secured.
Battery positive (+) cable should be connected
firstly.
yAnd the two posts of battery have to be greased
after connected the cables.
yMake sure that the battery post caps are
located in properly after the battery posts had
been serviced.
yIf fuse burned, it has to find out the cause and
solved it. And then replace with specified
capacity fuse.
Capacity
verification
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1. GENERAL INFORMATION
1-6
yWhen separating a connector, it locker has to
be unlocked firstly. Then, conduct the service
operation.
yDo not pull the wires as removing a connector
or wires. Hold the connector body.
yMake sure if the connector pins are bent,
extruded or loosen.
yInsert the connector completely.
If there are two lockers on two connector sides,
make sure the lockers are locked in properly.
Check if any wire loose.
yCheck if the connector is covered by the twin
connector boot completely and secured
properly.
yBefore terminal connection, check if the boot is
crack or the terminal is loose.
yInsert the terminal completely.
Check if the terminal is covered by the boot.
Do not let boot open facing up.
ySecure wires and wire harnesses to the frame
with respective wire bands at the designated
locations. Tighten the bands so that only the
insulated surfaces contact the wires or wire
harnesses.
yWire band and wire harness have to be
clamped secured properly.
yDo not squeeze wires against the weld or its
clamp.
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1. GENERAL INFORMATION
1-7
yDo not let the wire harness contact with rotating,
moving or vibrating components as routing the
harness.
yKeep wire harnesses far away from the hot
parts.
yRoute wire harnesses to avoid sharp edges or
corners and also avoid the projected ends of
bolts and screws.
yRoute harnesses so that they neither pull too
tight nor have excessive slack.
yProtect wires or wire harnesses with electrical
tape or tube if they contact a sharp edge or
corner. Thoroughly clean the surface where
tape is to be applied.
ySecure the rubber boot firmly as applying it on
wire harness.
yNever use wires or harnesses which insulation
has been broken. Wrap electrical tape around
the damaged parts or replace them.
yNever clamp or squeeze the wire harness as
installing other components.
Never Touch
Never too tight
Never clamp or
squeeze the wire
harness
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1. GENERAL INFORMATION
1-8
yDo not let the wire harness been twisted as
installation.
yWire harnesses routed along the handlebar
should not be pulled too tight or have excessive
slack, be rubbed against or interfere with
adjacent or surrounding parts in all steering
positions.
yBefore operating a test instrument, operator
should read the operation manual of the
instrument. And then, conduct test in
accordance with the instruction.
yWith sand paper to clean rust on connector
pins/terminals if found. And then conduct
connection operation later.
Do you know how to set the
instrument to its measurement
position and the insert
locations of its two probes?
Clean rust
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1. GENERAL INFORMATION
1-9
Specifications
MAKER SANYANG MODEL LC12W1-6
Overall Length 2070 mm Front Telescopic Fork
Overall Width 760 mm
Suspension
System Rear Unit Swing
Overall Height 1240 mm Front 100 / 80-16 50P
Dimension
Wheel Base 1380 mm Tire Specifications Rear 120 / 80-16 60P
Front 50 kg Front Disk (ψ220mm)
Rear 96 kg
Curb Weight
Total 146 kg
Brake System Rear Disk (ψ220mm)
Passengers/Weight Two /150 kg Max. Speed > 100 km/hr
Front 82 kg Performance Climb Ability Below 28°
Rear 214 kg Primary
Reduction Belt
Weight
Total Weight
Total 296 kg Secondary
Reduction Gear
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement
Vertical, below center,
incline 80°
Reduction
Transmission C.V.T.
Fuel Used Unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore ψ57 mm Muffler Expansion & Pulse
Type
Stroke 48.8 mm Exhaust Pipe Position and
Direction
Right side, and
Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 124.5 cc CO Below 2.0 g/ km
Compression Ratio 10.5 : 1 HC Below 0.8 g/ km
Max. HP 12.0 ps / 8,500 rpm
Exhaust
Concentrati
on
NOx Below 0.15g/ km
Max. Torque 1.06 kg-m / 7,000 rpm E.E.C. ─
Ignition C.D.I. P.C.V. ─
Engine
Starting System Electrical Starter Catalytic reaction control
system √
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1. GENERAL INFORMATION
1-10
MAKER SANYANG MODEL LC12W2-6
Overall Length 2070 mm Front Telescopic Fork
Overall Width 760 mm
Suspension
System Rear Unit Swing
Overall Height 1240 mm Front 100 / 80-16 50P
Dimension
Wheel Base 1380 mm Tire Specifications Rear 120 / 80-16 60P
Front 50 kg Front Disk (ψ220mm)
Rear 96 kg
Curb Weight
Total 146 kg
Brake System Rear Drum (ψ150mm)
Passengers/Weight Two /150 kg Max. Speed > 100 km/hr
Front 82 kg Performance Climb Ability Below 28°
Rear 214 kg Primary
Reduction Belt
Weight
Total Weight
Total 296 kg Secondary
Reduction Gear
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement
Vertical, below center,
incline 80°
Reduction
Transmission C.V.T.
Fuel Used Unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore ψ57 mm Muffler Expansion & Pulse
Type
Stroke 48.8 mm Exhaust Pipe Position and
Direction
Right side, and
Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 124.5 cc CO Below 2.0 g/ km
Compression Ratio 10.5 : 1 HC Below 0.8 g/ km
Max. HP 12.0 ps / 8,500 rpm
Exhaust
Concentrati
on
NOx Below 0.15g/ km
Max. Torque 1.06 kg-m / 7,000 rpm E.E.C. ─
Ignition C.D.I. P.C.V. ─
Engine
Starting System Electrical Starter Catalytic reaction control
system √
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1. GENERAL INFORMATION
1-11
MAKER SANYANG MODEL LC18W1-6
Overall Length 2070 mm Front Telescopic Fork
Overall Width 760 mm
Suspension
System Rear Unit Swing
Overall Height 1240 mm Front 100 / 80-16 50P
Dimension
Wheel Base 1380 mm Tire Specifications Rear 120 / 80-16 60P
Front 50 kg Front Disk (ψ220mm)
Rear 96 kg
Curb Weight
Total 146 kg
Brake System Rear Disk (ψ220mm)
Passengers/Weight Two /150 kg Max. Speed < 109 km/hr
Front 82 kg Two /150 kg Climb Ability Below 28°
Rear 214 kg Primary
Reduction Belt
Weight
Total Weight
Total 296 kg Secondary
Reduction Gear
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement
Vertical, below center,
incline 80°
Reduction
Transmission C.V.T.
Fuel Used Unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore ψ61 mm Muffler Expansion & Pulse
Type
Stroke 58.6 mm Exhaust Pipe Position and
Direction
Right side, and
Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 171.2 cc CO Below 2.0 g/ km
Compression Ratio 10 : 1 HC Below 0.3 g/ km
Max. HP 15.2 ps / 7,500 rpm
Exhaust
Concentrati
on
NOx Below 0.15g/ km
Max. Torque 1.47 kg-m / 6,000 rpm E.E.C. ─
Ignition Full Transistor Ignition P.C.V. ─
Engine
Starting System Electrical Starter Catalytic reaction control
system √
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1. GENERAL INFORMATION
1-12
MAKER SANYANG MODEL LC18W2-6
Overall Length 2070 mm Front Telescopic Fork
Overall Width 760 mm
Suspension
System Rear Unit Swing
Overall Height 1240 mm Front 100 / 80-16 50P
Dimension
Wheel Base 1380 mm Tire Specifications Rear 120 / 80-16 60P
50 kg 53 kg Front Disk (ψ220mm)
96 kg 82 kg
Curb Weight
146 kg 135 kg
Brake System Rear Drum (ψ150mm)
Passengers/Weight Two /150 kg Max. Speed < 109 km/hr
82 kg 75 kg Performance Climb Ability Below 28°
214 kg 170 kg Primary
Reduction Belt
Weight
Total Weight
296 kg 245 kg Secondary
Reduction Gear
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement
Vertical, below center,
incline 80°
Reduction
Transmission C.V.T.
Fuel Used Unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore ψ61 mm Muffler Expansion & Pulse
Type
Stroke 58.6 mm Exhaust Pipe Position and
Direction
Right side, and
Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 171.2 cc CO Below 2.0 g/ km
Compression Ratio 10 : 1 HC Below 0.3 g/ km
Max. HP 15.2 ps / 7,500 rpm
Exhaust
Concentrati
on
NOx Below 0.15g/ km
Max. Torque 1.47 kg-m / 6,000 rpm E.E.C. ─
Ignition Full Transistor Ignition P.C.V. ─
Engine
Starting System Electrical Starter Catalytic reaction control
system √
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1. GENERAL INFORMATION
1-13
Torque Values
The torque values listed in above table are for more important tighten torque values. Please see standard
values for not listed in the table.
Standard Torque Values for Reference
Type Tighten Torque Type Tighten Torque
5 mm bolt、nut 0.45~0.6kgf-m 5 mm screw 0.35~0.5kgf-m
6 mm bolt、nut 0.8~1.2kgf-m 6 mm screw、SH nut 0.7~ 1.1kgf-m
8 mm bolt、nut 1.8~2.5kgf-m 6 mm bolt、nut 1.0 ~1.4kgf-m
10 mm bolt、nut 3.0~4.0kgf-m 8 mm bolt、nut 2.4 ~3.0kgf-m
12 mm bolt、nut 5.0~6.0kgf-m 10 mm bolt、nut 3.5~4.5kgf-m
Engine Torque Values
Item Q’ty Thread Dia. (mm) Torque Value(kgf-m) Remarks
Cylinder head nut 4 8 2.0~2.4
Cylinder head right bolt 2 8 2.0~2.4
Cylinder head stud bolt (inlet pipe) 2 6 0.7~1.1
Cylinder head stud bolt (EX. pipe) 2 7 0.5~1.0
Tappet adjustment hole cap bolt 6 6 1.0~1.4
Tappet adjustment screw nut 4 5 0.7~1.1 Apply oil to thread
Spark plug 1 10 1.0~1.2
Carburetor insulator bolt 2 6 0.7~1.1
Cylinder stud bolt 4 8 0.7~1.1
Engine left cover bolt 7 6 1.1~1.5
Engine oil draining bolt 1 12 1.1~1.5
Engine oil strainer cap 1 30 1.3~1.7
Mission draining bolt 1 8 0.8~1.2
Mission filling bolt 1 10 0.8~1.2
Clutch driving plate nut 1 28 5.0~6.0
Clutch outer nut 1 12 5.0~6.0
Drive face nut 1 12 5.0~6.0
Flywheel nut 1 12 5.0~6.0
Crankcase bolts 7 6 0.8~1.2
Mission case bolt 7 8 2.0~2.4
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1. GENERAL INFORMATION
1-14
Frame Torque Values
Item Q’ty Thread Dia. (mm) Torque Value(kgf-m) Remarks
Stopper nut for engine hanger
rubber 1 8 1.8~2.2
Engine hanger nut 2 12 4.0~5.0
Engine hanger bolt 1 12 4.0~5.0
Engine connection bolt 1 10 3.5~4.5
Front wheel axle nut 1 12 5.0~7.0
Rear wheel shaft nut 1 14 10.0~12.0
Rear fork 2 8 4.0~5.0
Rear cushion upper bolt 2 10 3.5~4.5
Rear cushion under bolt 2 8 2.4~3.0
Nut for steering post 1 10 4.0~5.0
Front cushion 4 8 2.4~3.0
Brake lever nut 2 6 0.8~1.2
Nut for the rear brake arm 1 6 0.5~0.6
Front brake hose bolt 4 10 3.0~4.0
Front brake caliper bolt 4 6 3.0~3.5
Front brake disk mounting bolt 7 8 4.0~4.5
Air-bleed valve 1 5 0.5~0.6
Speedometer cable locking screw 1 5 0.15~0.3
Exhaust muffler bolt 3 8 3.2~3.8
Exhaust muffler connection nut 2 7 1.0~1.2
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1. GENERAL INFORMATION
1-15
Troubleshooting-Carburetor Model
A. Engine hard to start or can not be started
Check and ad
j
ustment Failure condition Possible causes
Loosen carburetor drain bolt
to check if there is gasoline
inside the carburetor.
Fuel supplied to
carburetor sufficient. No fuel is supplied to
Remove spark plug, install it
into spark plug cap, and
perform a spark test against
engine ground.
Perform cylinder
compression pressure test.
Check if sparks Weak sparks, no spark
at all.
Cylinder compression
pressure normal.
Low compression
pressure or no pressure.
Re-start by following the
starting procedures.
No ignition There are some signs of
ignition, but engine can
not be started.
Remove the spark plug again
and check it.
Remove carburetor after 30
minutes and connect a hose
onto fuel rich circuit. Then
blow the hose with air.
Dry spark plug Wet spark plug
Blowing in normal Blowing clogged
1. No fuel in fuel tank
2. Check if the pipes, fuel tank to carburetor
and intake vacuum, are clogged.
3. Float valve clogged
4. Lines in fuel tank evaporation system
clogged
5. Malfunction of fuel pump
6. Loosen or damaged fuel pump vacuum
hose
7. Fuel filter clogged
1. Malfunction of spark plug
2. Spark plug foul
3. Malfunction of CDI set
4. Malfunction of AC generator
5. Ignition coil is in open or short circuit
6. Ignition coil leads open or short circuit
7. Malfunction of main switch
1. Piston ring seized
2. Malfunction of cylinder valves
3. Worn cylinder and piston ring
4. Cylinder gasket leak
5. Sand hole in compression parts
1. Malfunction of throttle valve operation
2. Air sucked into intake manifold
3. Incorrect ignition timing
1. Fuel level in carburetor too high
2. Malfunction of throttle valve operation
3. Throttle valve opening too wide
1. Malfunction of automatic by- starter
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