KYMCO MX'er 125 User manual

PREFACE
This Service Manual describes the
technical features and servicing
procedures for the KYMCO MX’er
125/150.
Section 1 contains the precautions for
all operations stated in this manual.
Read them carefully before starting any
operation.
Section 2 is the removal/installation
procedures for the frame covers which
are subject to higher removal/installation
frequency during maintenance and
servicing operations.
Section 3 describes the inspection/
adjustment procedures, safety rules and
service information for each part, starting
from periodic maintenance.
Sections 4 through 17 give instructions
for disassembly, assembly and
inspection of engine, chassis frame and
electrical equipment.
Most sections start with an assembly or
system illustration and troubleshooting
for the section. The subsequent pages
give detailed procedures for the section.
KWANG YANG MOTOR CO., LTD.
OVERSEAS SALES DEPARTMENT
OVERSEAS SERVICE SECTION
TABLE OF CONTENTS
GENERAL INFORMATION 1
FRAME COVERS/EXHAUST MUFFLER 2
INSPECTION/ADJUSTMENT 3
LUBRICATION SYSTEM 4
FUEL SYSTEM 5
ENGINE REMOVAL/INSTALLATION 6
CYLINDER HEAD/VALVES 7
CYLINDER/PISTON 8
DRIVE AND DRIVEN PULLEYS 9
FINAL REDUCTION/TRANSMISSION
SYSTEM 10
CRANKCASE/CRANKSHAFT/
BALANCE SHAFT 11
FRONT WHEEL/FRONT BRAKE/
FRONT SUSPENSION/STEERING
SYSTEM 12
REAR WHEEL /SWING
ARM/HYDRAULIC BRAKE 13
BATTERY/CHARGING SYSTEM/A.C.
GENERATOR 14
IGNITION SYSTEM 15
STARTING SYSTEM 16
LIGHTS/SWITCHES 17
ONLY ATV ON ROAD AVAILABLE 18
The information and contents included
in this manual may be different from
the motorcycle in case specifications
are changed.
CHASSIS
ELECTRICAL
EQUIPMENT
ENGINE

1. GENERAL INFORMATION
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MX’er SYSTEM
1
__________________________________________________________________________________
GENERAL INFORMATION
SERIAL NUMBER ------------------------------------------------------------- 1-1
SPECIFICATIONS------------------------------------------------------------- 1-2
SERVICE PRECAUTIONS -------------------------------------------------- 1-4
TORQUE VALUES ------------------------------------------------------------ 1-12
SPECIAL TOOLS -------------------------------------------------------------- 1-14
LUBRICATION POINTS----------------------------------------------------- 1-15
CABLE & HARNESS ROUTING------------------------------------------- 1-18
WIRING DIAGRAM----------------------------------------------------------- 1-22
TROUBLESHOOTING ------------------------------------------------------- 1-23
1

1. GENERAL INFORMATION
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1
MX’er SYSTEM
SERIAL NUMBER
Location of Engine Serial Number
Location of Frame Serial Number

1. GENERAL INFORMATION
1
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2
MX’er SYSTEM
SPECIFICATIONS
Name & Model No. LA30AA, AB
Motorcycle Name & Type MX’er
Overall length (mm) 1600
Overall width (mm) 980
Overall height (mm) 990
Wheel base (mm) 1120
Engine type O.H.C.
Displacement (cc) 149.4
Fuel Used 92# nonleaded gasoline
Front wheel
74
Net weight (kg) Rear wheel
78
Total 152
Front wheel
80
Gross weight(kg)
Rear wheel
82
Total 162
Front wheel
20*7-8
Rear wheel
22*10-8
Ground clearance (mm) 130
Perform-
Breaking distance
(m)(ANSI)20.6 below
ance Min. turning radius (m) 3
Starting system Starting motor
Type Gasoline, 4-stroke
Cylinder arrangement Single cylinder
Combustion chamber type Semi-sphere
Valve arrangement O.H.C., chain drive
Bore x stroke (mm) 62 x 49.5
Compression ratio 9.7:1
Compression pressure
(kg/cm²)16.0
Max. output (ps/rpm) 11/7500
Max. torque (kg m/rpm) 1.1/5500
Intake Open 5.5°BTDC
Port (1mm) Close 27.5°ABDC
timing
Exhaust Open 36°BBDC
(1mm) Close 4°ATDC
Valve
clearance Intake 0.06
(cold) (mm) Exhaust 0.06
Idle speed (rpm) 1700rpm
Lubrication type Forced pressure &
wet sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity 1.0 liter
Oil exchanging
capacity 0.9 liter
Cooling Type Forced air cooling
Air cleaner type & No
Sponge
Fuel capacity 8.1 liters
Type PD
Float lever 14.8mm
Venturi dia.(mm) φ25
Throttle type PISTON
Type CDI
Ignition timing 15°BTDC/1700rpm
Contact breaker Non-contact point type
Spark plug
NGK
CR8E
Spark plug gap 0.6 0.7mm
Battery Capacity 12V8AH
Clutch
Type CVT
Type Helical gear
Operation Automatic centrifugal
type
Type Chain drive
Reduction
1st 2.8-0.95
ratio 2nd
7.226
Counter gear ratio 26.902
Front Caster angle
Axle Trail length
Ti
re pressure
Front
0.2
(kg/cm²)Rear 0.25
Turning Left 44°
angle Right 44°
Brake system
Rear
Disk brake
Drum brake
type Front Drum brake
Suspension
Front
Swing
type Rear Swing arm
Shock absorber
Front Swing
type Rear Swing arm
Frame type SP pipe
Tires
Engine
Lubrication
System
Fuel System
Carbureto
r
Electrical
Equipment
Ignition System
Power Drive System
Transmis- sion Gear
Reduction
Gear
Moving Device
Damping
Device

1. GENERAL INFORMATION
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3
MX’er SYSTEM
SPECIFICATIONS
Name & Model No. LA25AB
Motorcycle Name & Type MX’er
Overall length (mm) 1685
Overall width (mm) 980
Overall height (mm) 990
Wheel base (mm) 1120
Engine type OHC
Displacement (cc) 124
Fuel Used 92# nonleaded gasoline
Front wheel
74
Net weight (kg) Rear wheel
78
Total 152
Front wheel
80
Gross weight(kg)
Rear wheel
82
Total 162
Front wheel
20*7-8
Rear wheel
22*10-8
Ground clearance (mm) 130
Perform-
Breaking distance
(m)(ANSI)20.6 below
ance Min. turning radius (m) 2.5
Starting system Starting motor
Type Gasoline, 4-stroke
Cylinder arrangement Single cylinder
Combustion chamber type Semi-sphere
Valve arrangement O.H..C., chain drive
Bore x stroke (mm) 56.5x 49.5
Compression ratio 9.2:1
Compression pressure
(kg/cm²)14.0
Max. output (ps/rpm) 9.8/7500
Max. torque (kg m/rpm) 0.98/5500
Intake Open 5.5°BTDC
Port (1mm) Close 27.5°ABDC
Timin
g
Exhaust Open 36°BBDC
(1mm) Close 4°ATDC
Valve
clearance Intake 0.06
(cold) (mm) Exhaust 0.06
Idle speed (rpm) 1700rpm
Lubrication type Forced pressure &
wet sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity 1.0 liter
Oil exchanging
capacity 0.9 liter
Cooling Type Forced air cooling
Air cleaner type & No
Sponge
Fuel capacity 8.1 liters
Type PD
Piston dia. (mm) 14.8mm
Venturi dia.(mm) φ25
Throttle type PISTON
Type CDI
Ignition timing 15°BTDC/1700rpm
Contact breaker Non-contact point type
Spark plug NGK
CR8E
Spark plug gap 0.6 0.7mm
Battery Capacity 12V8AH
Clutch
Type CVT
Type Helical gear
Operation Automatic centrifugal
type
Type Chain drive
Reduction
1st 2.8-0.95
ratio 2nd
7.226Counter gear ratio 26.902
Front Caster angle
Axle Trail length
Ti
re pressure
Front
0.2
(kg/cm²)Rear 0.25
Turning Left 44°
angle Right 44°
Brake system
Rear
Disk brake
Drum brake
type Front Drum brake
Suspension
Front
Swing
type Rear Swing arm
Shock absorber
Front Swing
type Rear Swing arm
Frame type SP pipe
Lubrication
System
Tires
Engine
Fuel System
Carbureto
r
Electrical
Equipment
Ignition System
Power Drive System
Transmis- sion Gear
Reduction Gear
M
oving Device
Damping
Device

1. GENERAL INFORMATION
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4
MX’er SYSTEM
SERVICE PRECAUTIONS
nMake sure to install new gaskets, O-rings,
circlips, cotter pins, etc. when reassembling.
nWhen tightening bolts or nuts, begin with
larger-diameter to smaller ones at several
times, and tighten to the specified torque
diagonally.
nUse genuine parts and lubricants.
nWhen servicing the motorcycle, be sure to
use special tools for removal and installation.
nAfter disassembly, clean removed parts.
Lubricate sliding surfaces with engine oil
before reassembly.

1. GENERAL INFORMATION
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5
MX’er SYSTEM
nApply or add designated greases and
lubricants to the specified lubrication points.
nAfter reassembly, check all parts for proper
tightening and operation.
nWhen two persons work together, pay
attention to the mutual working safety.
nDisconnect the battery negative (-) terminal
before operation.
nWhen using a spanner or other tools, make
sure not to damage the motorcycle surface.
nAfter operation, check all connecting points,
fasteners, and lines for proper connection
and installation.
nWhen connecting the battery, the positive (+)
terminal must be connected first.
nAfter connection, apply grease to the battery
terminals.
nTerminal caps shall be installed securely.

1. GENERAL INFORMATION
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MX’er SYSTEM
nIf the fuse is burned out, find the cause and
repair it. Replace it with a new one
according to the specified capacity.
nAfter operation, terminal caps shall be
installed securely.
nWhen taking out the connector, the lock on
the connector shall be released before
operation.
nHold the connector body when connecting
or disconnecting it.
nDo not pull the connector wire.
nCheck if any connector terminal is bending,
protruding or loose.
Confirm
Capacity

1. GENERAL INFORMATION
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MX’er SYSTEM
nThe connector shall be inserted
completely.
nIf the double connector has a lock, lock it
at the correct position.
nCheck if there is any loose wire.
nBefore connecting a terminal, check for
damaged terminal cover or loose negative
terminal.
nCheck the double connector cover for
proper coverage and installation.
nInsert the terminal completely.
nCheck the terminal cover for proper
coverage.
nDo not make the terminal cover opening face
up.
nSecure wire harnesses to the frame with their
respective wire bands at the designated
locations.
Tighten the bands so that only the insulated
surfaces contact the wire harnesses.
Snapping!

1. GENERAL INFORMATION
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8
MX’er SYSTEM
nAfter clamping, check each wire to make
sure it is secure.
nDo not squeeze wires against the weld or its
clamp.
nAfter clamping, check each harness to make
sure that it is not interfering with any moving
or sliding parts.
nWhen fixing the wire harnesses, do not make
it contact the parts which will generate high
heat.
nRoute wire harnesses to avoid sharp edges
or corners. Avoid the projected ends of
bolts and screws.
nRoute wire harnesses passing through the
side of bolts and screws. Avoid the
projected ends of bolts and screws.
No Contact !

1. GENERAL INFORMATION
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MX’er SYSTEM
nRoute harnesses so they are neither pulled
tight nor have excessive slack.
nProtect wires and harnesses with electrical
tape or tube if they contact a sharp edge or
corner.
nWhen rubber protecting cover is used to
protect the wire harnesses, it shall be
installed securely.
nDo not break the sheath of wire.
nIf a wire or harness is with a broken sheath,
repair by wrapping it with protective tape or
replace it.
nWhen installing other parts, do not press or
squeeze the wires.
Do not pull
too tight!
Do not press
or squeeze
the wire.

1. GENERAL INFORMATION
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MX’er SYSTEM
nAfter routing, check that the wire harnesses
are not twisted or kinked.
nWire harnesses routed along with handlebar
should not be pulled tight, have excessive
slack or interfere with adjacent or
surrounding parts in all steering positions.
nWhen a testing device is used, make sure to
understand the operating methods thoroughly
and operate according to the operating
instructions.
nBe careful not to drop any parts.
nWhen rust is found on a terminal, remove the
rust with sand paper or equivalent before
connecting.
Do you understand
the instrument? Is
the instrument set
correctly?
Remove Rust !

1. GENERAL INFORMATION
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11
MX’er SYSTEM
nSymbols:
The following symbols represent the
servicing methods and cautions included in
this service manual.
:Apply engine oil to the
specified points. (Use
designated engine oil for
lubrication.)
:Apply grease for lubrication.
:Transmission Gear Oil (90#)
:Use special tool.
:Caution
:Warning
Engine Oil
Grease
Gear Oil
Special

1. GENERAL INFORMATION
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12
MX’er SYSTEM
TORQUE VALUES
STANDARD TORQUE VALUES
Item
Torque (kg
f
-
m)
Item
Torque (kg
f
-
m)
5mm bolt, nut
6mm bolt, nut
8mm bolt, nut
10mm bolt, nut
12mm bolt, nut
14mm bolt, nut
0.45 0.6
0.8 1.2
1.8 2.5
3.0 4.0
5.0 6.0
6.0 8.0
4mm screw
5mm screw
6mm screw, SH bolt
6mm flange bolt and nut
8mm flange bolt and nut
10mm flange bolt and nut
0.15 0.4
0.3 0.5
0.7 1.1
1.0 1.4
2.4 3.0
3.5 4.5
Torque specifications listed below are for important fasteners.
ENGINE
Item Q‘ty Thread dia.(mm)
Torque (kgf-m)
Remarks
Stud bolt
Oil filter screen cap
Seat ball stopper bolt
Bearing hold
L cover
Stud bolt
Cam holder
Tappet ADJ nut
Pivot tensioner
Lifter tensioner
Lifter tensioner
MISTON oil drive bolt
Driver face
Clutch outer
Oneway clutch
Balancer shaft
ACG flywheel
Spark plug
Drain bolt mission
Drain plug
Clamper wre harness
Motor srart
Oil pump
Oil pump sprocket
Head CYL bolt
Drive plate nut
Startor
4
1
1
1
8
4
4
2
1
2
1
9
1
1
3
1
1
1
1
1
1
2
2
2
2
1
4
8
30
14
6
6
6
8
6
8
6
6
6
12
12
8
16
14
8
8
12
6
6
6
6
6
22
5
0.7 1.1
1.0 2.0
4.5 5.0
1.0 1.2
1.0 1.4
0.7 1.1
1.8 2.2
1.4 1.8
0.8 1.2
1.0 1.4
0.35 0.5
0.8 1.2
5.5 6.5
5.0 6.0
2.4 3.0
4.0 5.0
5.0 6.0
1.1 2.3
0.8 1.2
2.0 3.0
0.8 1.2
0.8 1.2
0.8 1.2
0.8 1.2
0.8 1.2
5.0 6.0
0.8 1.2

1. GENERAL INFORMATION
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13
MX’er SYSTEM
Item Q‘ty Thread dia.(mm) Torque (kgf-m)
Remarks
R cover
Head cover
Cap R cover
Guide star change handle
Sprocket drive plate
Carburetor
Check bolt oil
9
4
1
3
2
2
1
6
6
6
6
6
6
10
0.8 1.2
0.8 1.2
0.8 1.2
0.8 1.2
1.0 1.6
0.8 1.2
1.0 1.5
FRAME
Item Q‘ty Thread dia.(mm) Torque (kgf-m)
Remarks
Steering stem nut
Swing arm nut
Rear wheel nut
Front wheel nut
Rear shock absorber upper mount bolt
Front shock absorber upper mount bolt
Front shock absorber lower mount bolt
Rear fork axle
Rear hub nut
Rear wheel shaft nut
Rear engine bracket up bolt
Rear engine bracket bolt
Engine hanger bracket bolt
Exhaust muffler lock bolt
1
4
2
2
1
2
2
1
4
2
1
1
1
2
14
10
14
14
10
10
10
14
12
32
10
10
10
8
6.0 8.0
4.0 5.0
6.0 8.0
6.0 8.0
3.5 4.5
3.5 4.5
3.5 4.5
6.0 8.0
6.0 8.0
11.0 13.0
3.5 4.5
3.5 4.5
3.5 4.5
3.2 3.8

1. GENERAL INFORMATION
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14
MX’er SYSTEM
SPECIAL TOOLS
Tool Name Tool No. Remarks Ref. Page
Flywheel puller E003
Lock nut wrench E009
Valve adjuster E012
Valve spring compressor E040
Oil seal and bearing install E014
Universal holder E017
Flywheel holder E021
Clutch spring compressor E027
Bearing puller E008
Bearing puller E018
Bearing puller E020
Bearing puller E031
Nut wrench F010
Float level gauge

1. GENERAL INFORMATION
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15
MX’er SYSTEM
LUBRICATION POINTS
ENGINE
Lubrication Points Lubricant
Valve guide/valve stem movable part
Cam lobes
Valve rocker arm friction surface
Cam chain
Cylinder lock bolt and nut
Piston surroundings and piston ring grooves
Piston pin surroundings
Cylinder inside wall
Connecting rod/piston pin hole
Connecting rod big end
Crankshaft right side oil seal
Crankshaft one-way clutch movable part
Oil pump drive chain
Balance gear
A.C. generator
Starter one-way clutch
Bearing movable part
O-ring face
Oil seal lip
•Genuine KYMCO Engine Oil (SAE15W-40)
•API SG Engine Oil
Transmission gear and movable parts Gear oil: SAE90#

1. GENERAL INFORMATION
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16
MX’er SYSTEM
FRAME
The following is the lubrication points for the frame.
Use general purpose grease for parts not listed.
Apply clean engine oil or grease to cables and movable parts not specified. This will avoid abnormal
noise and rise the durability of the motorcycle.
Steering knuckle/Thrust
Cover/Bush/Collar
Steering Column Upper
Rear Brake Cable
Front Brake
camshaft/Oil
Seal/O-ring
Throttle Cable
Front Brake Cable
Steer
ing Column Lower
Front Wheel
Oil Seal
Front Arm Bush
Front Brake
camshaft/Oil
Seal/O-ring
Front Wheel
Oil Seal
Steering knuckle/Thrust
Cover/Bush/Collar
Front Arm Bush

1. GENERAL INFORMATION
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17
MX’er SYSTEM
Sprocket hub/Rear
Axle Hub Collar/Oil
Seal/Bearing
Rear Brake Cam/ Axle
Hub Collar/Oil
Seal/Bearing
Driven Sprocket
Swing arm Thrust
Cover

1. GENERAL INFORMATION
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MX’er SYSTEM
CABLE & HARNESS ROUTING
Throttle Cable
Rear Brake Cable
Right
Front Brake
Cable
Handlebar Switch Lead
Front Brake
Cable
Left
Front Brake
Cable