Sym JOYRIDE 125 User manual

Joyride 125 / 200i EVO
X’PRO RV125 / 200 EFi
SERVICE MANUAL
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 JOYRIDE 125/200i EVO, X’PRO RV 125/200 EFi
motorcycle. 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, JOYRIDE 125/200i EVO, X’PRO
RV 125/200 EFi, are 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.
Homepage Contents

HowtoUseThisManual
This service manual describes basic information of different system parts and
system inspection & service for Sanyang JOYRIDE 125/200i EVO, X’PRO RV
125/200 EFi 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.
Th third to the thirteenth chapter covers the engine and driving systems.
The fourteenth to the seventeenth is contained the parts set of assembly body.
The eighteenth chapter is electrical equipment.
The nineteenth chapter is special tool.
The twentieth 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 Illustration” in the PDF version, and can be access to these items
by clicking on the buttons.
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, on 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.
Homepage Contents

Contents
Page Content Index
1-1 ~ 1-20 General Information
1
2-1 ~ 2-12 Maintenance Information 2
3-1 ~ 3-8 Lubrication System 3
4-1 ~ 4-12 Fuel System-Carburetor 4
5-1 ~ 5-56 Fuel Injection System 5
6-1 ~ 6-14 Engine Removal 6
7-1 ~ 7-14 Cylinder Head / Valve 7
8-1 ~ 8-8 Cylinder / Piston 8
9-1 ~ 9-14 V-Belt Drive System 9
10-1 ~ 10-8 Final Drive Mechanism 10
11-1 ~ 11-8 AC Generator / Starting Clutch 11
12-1 ~ 12-8 Crankshaft / Crankcase 12
13-1 ~ 13-12 Cooling System 13
14-1 ~ 14-10 Body Cover 14
15-1 ~ 15-10 Brake System 15
16-1 ~ 16-12 Steering / Front Wheel / Front Cushion 16
17-1 ~ 17-6 Muffler / Rear Wheel / Rear Cushion 17
18-1 ~ 18-22 Electrical System 18
19-1 ~ 19-12 Special Tools 19
20-1 ~ 20-4 Wiring Diagram
20
Homepage Contents

Mechanism Illustration
Front winker
Fuel tank
cap
Luggage box
Light switch / start switch /
engine stop (hazard) switch
Dimmer switch / winker switch /
horn switch / seat open (passing)
switch
Muffler
Reserved tank
cap
Coolant filler
cap
Ignition / Seat open
switch
Fuse
Main switch
Fuel tank /
fuel pump
Side stand
ECU /
throttle body
B
ack mirror
Battery
Front brake
lever
Rear brake
lever
Home page Contents
Main stand
Air cleaner
Taillight /
rear winker

1. GENERAL INFORMATION
1-1
Symbols and Marks .............................. 1-1
General Safety....................................... 1-2
Service Precautions.............................. 1-3
Specifications........................................ 1-5
Torque Values ....................................... 1-9
Cables and Harness Routing..............1-11
Troubleshooting-Carburetor model ...1-12
Troubleshooting-EFi model ................1-16
Lubrication Points ...............................1-20
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 20 JASO FC class oil. Warranty will not cover the
damage that caused by not apply with the limited engine oil.
(Recommended oil: MAX-2 serial oils)
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).
Contents
Homepage
1

1.GENERALINFORMATION
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
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
Used engine oil
Caution
Hot components
Caution
Battery
Caution
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
Brake fluid
Caution
Exhaust contains toxic gas which may cause
one to lose consciousness and even result in
death.
‧ Battery emits explosive gases; flame is
strictly prohibited. Keep the place 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.
Gasoline is highly flammable, and may
explode under some conditions, keep it away
from children.
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.
Inhaling brake shoe or pad ash may cause
disorders and cancer of the breathing system.
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.
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.
To this chapter contents

1. GENERAL INFORMATION
1-3
Service Precautions
zAlways use with Sanyang genuine parts and
recommended oils. Using non-designed parts
for Sanyang motorcycle may damage the
motorcycle.
zSpecial tools are designed for remove and
install of components without damaging the
parts being worked on. Using wrong tools
may result in parts damaged.
zWhen 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.
zClean 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.
zWash 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.
zNever bend or twist a control cable to prevent
unsmooth control and premature worn out.
zRubber 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.
zWhen 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.
zStore complex components such as
transmission parts in the proper assemble
order and tie them together with a wire for
ease of installation later.
zNote the reassemble position of the important
components before disassembling them to
ensure they will be reassembled in correct
dimensions (depth, distance or position).
zComponents not to be reused should be
replaced when disassembled including
gaskets metal seal rings, O-rings, oil seals,
snap rings, and split pins.
Caution
In addition to damaging paint finish, brake oil
can also damage the structural integration of
plastic or rubber parts.
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1.GENERALINFORMATION
1-4
zThe 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.
zTighten 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.
zWhen 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.
zRemove residues of the old gasket or sealant
before reinstallation, grind with a grindstone if
the contact surface has any damage.
zThe 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.
zRubber and plastic boots should be properly
reinstalled to the original correct positions as
designed.
zThe 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.
zLubricate the rotation face as assembling.
Check if positions and operation for installed
parts is in correct and properly.
Manufacturer's
name
Groove
Clamp
Connection
Boots
To this chapter contents

1. GENERAL INFORMATION
1-5
Specifications
Maker SANYANG MODEL LF12W-6/F
Overall Length 2100 mm Front Telescopic Fork
Overall Width 760 mm Suspension
System Rear Unit Swing
Overall Height 1390 mm Front 110 / 90-13 56P
Wheel Base 1440 mm Tire
Specifications Rear 130 / 70-12 64L
Front 63 kg Front
Disk (ψ273mm)
Rear 93 kg
Curb
Wei
g
ht
Total 156 kg
Brake System Rear Disk (ψ200mm)
Passengers/
Weight Two /170 kg Max. Speed >100 km/hr
Front 97 kg Climb Ability 28°
Rear 229 kg Primary Reduction Belt
WEIGHT DIMENSION
Total Weight
Total 326 kg Secondary
Reduction Gear
Type Gasoline Clutch
3-piece centrifugal, dry
type
Position and
arrangement Horizontal, below center, CYL incline 80°
PERFORMANCE
Transmission C.V.T.
Fuel Used >92 Unleaded gasoline Speed meter 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93 – 112 dB/A
Bore Ø 57 mm Muffler Expansion & Pulse Type
Stroke 48.8 mm
Exhaust Pipe Position
and Direction Right Side & Backward
Cylinder
Number/Arran
gement Single Cylinder Lubrication System Forced Circulation &
Splashing
Displacement 124.5 cc Co
〈 2.0 g/km
Compression Ratio 10.5 : 1 HC 〈 0.8 g/km
Max. HP 13 ps / 8500 rpm
Exhaust
Concentratio
n
NOx 〈 0.15 g/km
Max. Torque 1.1 kg-m / 6500 pm E.E.C. -
Ignition C.D.I P.C.V. -
ENGINE
Starting System Kick & Electrical Starter Catalytic Converter Equipped
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1.GENERALINFORMATION
1-6
Specifications
Maker SANYANG MODEL LF12W2-7
Overall Length 2100 mm Front TELESCOPIC FORK
Overall Width 760 mm Suspension
System Rear Unit SWING
Overall Height 1390 mm Front 110 / 90-13 56P
Wheel Base 1440 mm Tire
Specifications Rear 130 / 70-12 64L
Front 63 kg Front
DlSK (ψ273mm)
Rear 93 kg
Brake System Rear DlSK (ψ200mm)
Curb
Wei
g
ht
Total 156 kg
Passengers/
Weight Two /170 kg Max. Speed >100 km/hr
Front 97 kg Climb Ability 28°
Rear 229 kg Primary Reduction BELT
WEIGHT DIMENSION
Total Weight
Total 326 kg Secondary
Reduction GEAR
Type Gasoline Clutch
3-piece centrifugal, dry
type
Position and
arrangement Horizontal, below center, CYL incline 80°
PERFORMANCE
Transmission C.V.T.
Fuel Used >92 Unleaded gasoline Speed meter 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93 – 112 dB/A
Bore Ø 57 mm Muffler Expansion & Pulse Type
Stroke 48.8 mm
Exhaust Pipe Position
and Direction Right Side & Backward
Cylinder
Number/Arran
gement Single Cylinder Lubrication System Forced pressure and wet
sump
Displacement 124.5 cc Co
〈 2.0 g/km
Compression Ratio 10.5 : 1 HC 〈 0.8 g/km
Max. HP 13 ps / 8500 rpm
Exhaust
Concentratio
n
NOx 〈 0.15 g/km
Max. Torque 1.1 kg-m / 6500 pm E.E.C. -
Ignition Full Transistor Ignition P.C.V. Equipped
ENGINE
Starting System Electrical Starter Catalytic converter Equipped
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1. GENERAL INFORMATION
1-7
Specifications
Maker SANYANG MODEL LF18W-A/W3-H/W5-C
Overall Length 2100 mm Front TELESCOPIC FORK
Overall Width 760 mm Suspension
System Rear UNlT SWING
Overall Height 1390 mm Front 110 / 90-13 56P
Wheel Base 1440 mm Tire
Specifications Rear 130 / 70-12 64L
Front 63 kg Front
DlSK (ψ273mm)
Rear 93 kg
Net
Weight
Total 156 kg
Brake System Rear DlSK (ψ200mm)
Passengers/
Weight Two /170 kg Max. Speed >109 km/hr
Front 97 kg Climb Ability 28°
Rear 229 kg Primary Reduction BELT
WEIGHT DIMENSION
Total Weight
Total 326 kg Secondary
Reduction GEAR
Type Gasoline Clutch
3-piece centrifugal, dry
type
Position and
arrangement Horizontal, below center, CYL incline 80°
PERFORMANCE
Transmission C.V.T.
Fuel Used >92 Unleaded gasoline Speed meter 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93 – 112 dB/A
Bore Ø 61 mm Muffler Expansion & Pulse Type
Stroke 58.6 mm
Exhaust Pipe Position
and Direction Right Side & Backward
Cylinder
Number/Arran
gement Single Cylinder Lubrication System Forced pressure and wet
sump
Displacement 171.2 cc Co
〈 12.0 g/km
Compression Ratio 10 : 1 HC 〈 1.0 g/km
Max. HP 13 / 8000 ps/rpm
Exhaust
Concentratio
n
NOx -
Max. Torque 1.2 / 6000 kg-m/rpm E.E.C. -
Ignition C.D.I. P.C.V. Equipped
ENGINE
Starting System Kick & Electrical Starter Catalytic converter Equipped
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1.GENERALINFORMATION
1-8
Specifications
Maker SANYANG MODEL LF18W-6/W1-9/W2-7/W4-8
Overall Length 2100 mm Front TELESCOPIC FORK
Overall Width 760 mm Suspension
System Rear UNlT SWING
Overall Height 1390 mm Front 110 / 90-13 56P
Wheel Base 1440 mm Tire
Specifications Rear 130 / 70-12 64L
Front 63 kg Front DlSK (ψ273mm)
Rear 93 kg
Brake System Rear DlSK (ψ200mm)
Curb
Wei
g
ht
Total 156 kg
Passengers/
Weight Two /170 kg Max. Speed >109 km/hr
Front 97 kg Climb Ability 28°
Rear 229 kg Primary
Reduction BELT
WEIGHT DIMENSION
Total Weight
Total 326 kg Secondary
Reduction GEAR
Type Gasoline Clutch 3-piece centrifugal, dry type
Position and
arrangement Horizontal, below center, CYL incline 80°
PERFORMANCE
Transmission C.V.T.
Fuel Used >92 Unleaded gasoline Speed meter 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93 – 112 dB/A
Bore Ø 61 mm Muffler Expansion & Pulse Type
Stroke 58.6 mm
Exhaust Pipe Position
and Direction Right Side & Backward
Cylinder
Number/Arran
gement Single Cylinder Lubrication System Forced pressure and wet
sump
Displacement 171.2 cc Co
〈 2.0 g/km
Compression Ratio 10 : 1 HC 〈 0.3 g/km
Max. HP 15 / 8000 ps/rpm
Exhaust
Concentratio
n
NOx 〈 0.15 g/km
Max. Torque 1.35 / 6500 kg-m/rpm E.E.C. -
Ignition Full Transistor Ignition P.C.V. - / Equipped
ENGINE
Starting System Electrical Starter Catalytic converter Equipped
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1. GENERAL INFORMATION
1-9
Torque Values
Item Q’ty
Thread Dia.
(mm) Torque Value (Kgf-m) Remarks
Cylinder head bolt 4 8 2.0-2.4
Valve clearance adjust nut 4 5 0.7-1.1 Apply oil to thread
Spark plug 1 10 1.0-1.4
L. Crankcase cover bolts 7 6 1.1-1.5
Crankcase bolts 7 6 0.8-1.2
Oil drain bolt 1 8 1.1-1.5
Oil strainer cap 1 30 1.3-1.7
Gear oil drain bolt 1 6 1.0-1.4
Gear oil inspection bolt 1 6 1.0-1.4
Transmission cover bolt 7 6 1.0-1.4
Flywheel bolt 1 14 5.0-6.0
Clutch driving plate bolt 1 28 5.0-6.0
Driving disc nut 1 12 5.0-6.0
Clutch outer cover nut 1 10 3.5-4.5
Transmission cover bolts 7 6 1.0-1.4
Stopper nut for engine hanger
bracket 1 8 1.8-2.2
Nut for engine hanger bracket 1 10 4.0-5.0
Bolt for engine hanger bracket 1 10 4.0-5.0
Engine mounting bolt 1 10 3.5-4.5
Front wheel shaft nut 1 12 5.0-7.0
Rear wheel shaft nut 1 14 11.0-13.0
Bolt for rear shock absorber (upper) 2 10 3.5-4.5
Bolt for rear shock absorber (under) 2 8 2.4-3.0
Bolt for steering rod 1 10 4.0-5.0
Front shock absorber 4 8 2.4-3.0
Brake arm bolts 2 6 0.8-1.2
Brake hose bolts 4 10 3.3-3.7
Bolt for brake caliper 4 10 3.0-3.5
Bolts for the lining guide pin 4 6 1.6-2.0
Brake disk bolts 7 10 4.0-4.5
Mounting screw for speedometer
cable 1 5 0.15-0.3
Muffler bolts 4 8 3.2-3.8
Mounting bolts for exhaust pipe
connection 2 7 1.0-1.2
The torque values listed in above table are for more important tighten torque values. Please see
standard values for not listed in the table.
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1.GENERALINFORMATION
1-10
Standard Torque Values for Reference
Type Torque value kgf-m
5 mm Bolt, Nut 0.45 - 0.6
6 mm Bolt, Nut 0.8 - 1.2
8 mm Bolt, Nut 1.8 - 2.5
10 mm Bolt, Nut 3.0 - 4.0
12 mm Bolt, Nut 5.0 - 6.0
5 mm Screw 0.35 - 0.5
6 mm Screw & 6mm bolt with 8mm head 0.7 - 1.1
6 mm Flange bolt, nut 1.0 - 1.4
8 mm Flange bolt, nut 2.4 - 3.0
10 mm Flange bolt, nut 3.5 - 4.5
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1. GENERAL INFORMATION
1-11
Cables and Harness Routing
Note the following when routing cables
and wire harnesses:
•A loose wire, cable or harness may cause
safety hazard. After clamping, check each
wire to make sure it is secured.
•Do not squeeze wires against the weld or its
clamp.
•Secure 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.
•Route harnesses so that they neither pull too
tight nor have excessive slack.
•Protect wires or wire harnesses with electrical
tape or tube if they contact a sharp edge or
corner.
•Route wire harnesses to avoid sharp edges
or corners.
•Avoid the projected ends of bolts and screws.
•Keep wire harnesses far away from the
exhaust pipes and other hot parts.
•Be sure grommets are seated in their groves
properly.
•After clamping, check each harness to be
certain that it is not interfered with any
moving or sliding parts.
•After routing, check that the wire harnesses
are not twisted or kink.
•Wire 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.
•Thoroughly clean the surface where tape is to
be applied.
•Wrap electrical tape around the damaged
parts or replace them.
○：correct
╳：wrong
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1.GENERALINFORMATION
1-12
Troubleshooting-Carburetor model
A. Engine hard to start or can not be started
Check and adjustment Failure condition Possible causes
Loosen carburetor drain bolt
to check if there is gasoline
inside the carbureto
r
.
Fuel supplied to
carburetor sufficient. No fuel is supplied to carburetor.
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
s
p
ark 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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1. GENERAL INFORMATION
1-13
B. Engine run sluggish (Speed does not pick up, lack of power)
Check and adjustment Fault condition Probable causes
Try gradual acceleration and
check engine speed.
Engine speed can be
increased. Engine speed can not be increased.
Check ignition timing
(Using ignition lamp)
Check cylinder compression
pressure (using compression
pressure gauge)
Ignition timing correct Incorrect ignition timing
Compression pressure
correct No compression pressure
Check if carburetor jet is
clogged
No clogged Clogged
Remove spark plug
Check if engine over
No foul or discoloration Fouled and discoloration
No knock Knock
1. Air cleaner clogged
1. Poor fuel supply
2. Lines in fuel tank evaporation system
clogged
3. Exhaust pipe clogged
4. Fuel level too low in carburetor
5. Fuel nozzle clogged in carburetor.
1. Malfunction of CDI
2. Malfunction of AC alternator
1. Cylinder & piston ring worn out
2. Cylinder gasket leaked
3. Sand hole in compression parts
4. Valve deterioration
5. Seized piston ring
1. Remove foreign
1. Remove dirt
2. Incorrect spark plug heat range
1. Piston and cylinder worn out
2. Lean mixture
3. Poor fuel quality
4. Too much carbon deposited in
combustion chamber
5. Ignition timing too advanced
6. Poor circuit on the cooling system
Normal Engine overheat
Continually drive in
acceleration or high speed. 1. Too much carbon deposited in
combustion chamber
2. Lean mixture
3. Poor fuel quality
4. Ignition timing too advanced
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1.GENERALINFORMATION
1-14
C. Engine runs sluggish (especially in low speed and idling)
D. Engine runs sluggish (High speed)
Check and adjustment Fault condition Probable causes
Check ignition timing
(Using ignition lamp)
Check for fuel supplying
system in automatic fuel cup
Check if carburetor clogged
1. Incorrect ignition timing (malfunction
of CDI or AC alternator)
1. Rich mixture (loosen the screw)
2. Lean mixture (tighten the screw)
1. Poor heat insulation gasket
2. Carburetor lock loose
3. Poor intake gasket
4. Poor carburetor O-ring
5. Vacuum hose crack
1. Spark plug fouled
2. Malfunction of CDI
3. Malfunction of AC generator
4. Malfunction of ignition coil
5. Open or short circuit in spark plug
leads
6. Malfunction of main switch
1. Insufficient fuel in fuel tank
2. Fuel filter clogged
3. Restricted fuel tank vent
Good Poor
Good spark Poor
No air sucked Air sucked
Good Poor
Normal Abnormal
Air sucked through
carburetor gasket
Adjust the air screw of
carburetor
Remove spark plug, install
spark plug into spark plug
cap and perform spark test
against engine ground.
Check and adjustment Fault condition Probable causes
Check ignition timing
1. Malfunction of CDI
2. Malfunction of AC alternator
Normal Abnormal
No clogged Clogged 1. Cleaning
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1. GENERAL INFORMATION
1-15
E. Clutch, Driving And Driving Pulley
1. Clutch ling spring broken
2. Clutch outer cover stickled with clutch balance
weights
3. Connection parts in clutch and shaft worn out or
burned
Engine can be started but
motorcycle can not be moved.
FAULT CONDITIONS PROBABLE CAUSES
1. Driving belt worn out or deformation
2. Driving disk damaged
3. Driving pulley spring broken
4. Clutch ling broken
5. Driving slide-shaft gear groove broken
6. Transmission gear damaged
Engine running and misfire as
motorcycle initial forward moving or
jumping suddenly (rear wheel
rotating as engine in running)
Poor initial driving
(Poor climbing performance)
1. Driving belt worn out or deformation
2. Balance weight roller worn out
3. Driving sliding gear shaft worn out
4. Driving disk spring deformation
5. Driving sliding gear shaft worn out
6. Greased in driving belt and sliding gear.
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