KYMCO 150 MXU - User manual

KYMCO
SERVICE MANUAL
MXU 150
MX’er 150/125
Issued: 08.06.2005

By KWANG YANG Motor Co., Ltd.
First Edition, Jun 2005
All rights reserved. Any reproduction or
unauthorized use without the written permission of
KWANG YANG Motor Co., Ltd.
is expressly prohibited.
4122-LCA4/LLB1-S00

PREFACE
This Service Manual describes the
technical features and servicing
procedures for the KYMCO ATV
150/125.
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 18 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
CHASSIS
ELECTRICAL
EQUIPMENT
ENGINE
The information and contents included in
this manual may be different from the ATV
in case specifications are changed.
KYMCO reserves the right to make
changes at any time without notice and
without incurring any obligation.

1. GENERAL INFORMATION
1-0
ATV 150/125
1
__________________________________________________________________________________
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GENERAL INFORMATION
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SERIAL NUMBER---------------------------------------------------------- 1- 1
SPECIFICATIONS ---------------------------------------------------------- 1- 2
SERVICE PRECAUTIONS ------------------------------------------------ 1- 5
TORQUE VALUES --------------------------------------------------------- 1-13
SPECIAL TOOLS ----------------------------------------------------------- 1-15
LUBRICATION POINTS -------------------------------------------------- 1-16
CABLE & HARNESS ROUTING (MX’er 150/125) ------------------- 1-19
CABLE & HARNESS ROUTING (MXU 150) ------------------------- 1-23
WIRING DIAGRAM-------------------------------------------------------- 1-28
TROUBLESHOOTING----------------------------------------------------- 1-32
1

1. GENERAL INFORMATION
1-1
ATV 150/125
SERIAL NUMBER
Location of Engine Serial Numbe
r
Location of Frame Serial Numbe
r

1. GENERAL INFORMATION
1-2
ATV 150/125
SPECIFICATIONS (MX’er 150)
Model No. LA30
ATV Name MX’er 150
Overall length 1600 mm (64 in)
Overall width 980 mm (39.2 in)
Overall height 990 mm (39.6 in)
Wheel base 1120 mm (44.8 in)
Engine type O.H.C.
Displacement 149.4 cc (9.1 cu-in)
Fuel Used 92# nonleaded gasoline
Front wheel 74 kg (162.8 lbs)
Dry weight Rear wheel 78 kg (171.6 lbs)
Total 152 kg (334.4 lbs)
Front wheel 80 kg (176 lbs)
Gross weight Rear wheel 82 kg (180.4 lbs)
Total 162 kg (356.4 lbs)
Front wheel 20*7-8
Rear wheel 22*10-8
Ground clearance 130 mm (5.2 in)
Perform- Breakin
g
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 62 x 49.5 mm
(2.48 x1.98 in)
Compression ratio 9.7:1
Compression pressure
(kg/cm
² ²)
1600 kPa (16 kg/c
m
2,
227.2 psi)
Open 5.5 BTDC
Intake Close 27.5 ABDC
Open 36 BBDC
Exhaust Close 4 ATDC
Intake 0.06 mm (0.0024 in)
Valve clearance Exhaust 0.06 mm (0.0024 in)
Idle speed 1700 rpm
Lubrication type Forced
p
ressure &
wet sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity 1 liter (0.88 lmp qt,
1.06 US qt)
Oil exchanging
capacity
0.9 liter (0.79 lmp qt,
0.95 US qt)
Cooling Type Air cooling
Air cleaner type & No Sponge
Fuel capacity 8.1 liters (1.7 lmp gal,
2.11 Usgal)
Type PD
Float lever 14.8 mm (0.592 in)
Venturi dia. !25 mm (!1 in)
Throttle type PISTON
Type CDI
Ignition timing 15 BTDC/1700rpm
Contact breaker Non-contact point type
Spark plug (NGK) DE-8EA
Spark plug gap 0.6Д0.7 mm
(0.024Д0.028 in)
Battery Capacity 12V8AH
Clutch type CVT
Primary reduction
system Helical gear/spur gear
Secondary reduction
system Chain drive
Primary reduction ratio 2.8-0.95
Secondary reduction
ratio 7.226
Reverse ratio 26.902
FR/RR tire rolling
circumference
1596/1756 mm
(63.84/70.24 in)
Front 20 kPa (0.2 kg/cm2,2.84
psi)
Tire pressure Rear 25 kPa (0.25 kg/cm2,
3.55 psi
Turning Left 44
angle Right 44
Rea
r
Disk brake Drum brake
Brake system type Front Drum brake
Sus
p
ension Fron
t
Swin
g
type Rear Swing arm
Shock Front Swing
type Rear Swing arm
Frame type Steel tube type
Tires
Lubrication System
Fuel S
y
stem
Carbureto
r
Electrical Equipment
I
g
nition S
y
stem
Damping Device
Moving Device
Power Drive System
Engine

1. GENERAL INFORMATION
1-3
ATV 150/125
(MX’er 125)
Model No. LA25
ATV Name MX’er 125
Overall length 1685 mm (67.4 in)
Overall width 980 mm (39.2 in)
Overall height 990 mm (39.6 in)
Wheel base 1120 mm (44.8 in)
Engine type O.H.C.
Displacement 124 cc (7.55 cu-in)
Fuel Used 92# nonleaded gasoline
Front wheel 74 kg (162.8 lbs)
Dry weight Rear wheel 78 kg (171.6 lbs)
Total 152 kg (334.4 lbs)
Front wheel 80 kg (176 lbs)
Gross weight Rear wheel 82 kg (180.4 lbs)
Total 162 kg (356.4 lbs)
Front wheel 20*7-8
Rear wheel 22*10-8
Ground clearance 130 mm (5.2 in)
Perform- Breakin
g
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 56.5 x 49.5 mm
(2.26 x1.98 in)
Compression ratio 9.2:1
Compression pressure
(kg/cm
² ²)
1400 kPa (14 kg/c
m
2,
198.8 psi)
Open 5.5 BTDC
Intake Close 27.5 ABDC
Open 36 BBDC
Exhaust Close 4 ATDC
Intake 0.06 mm (0.0024 in)
Valve clearance Exhaust 0.06 mm (0.0024 in)
Idle speed 1700 rpm
Lubrication type Forced
p
ressure &
wet sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity 1 liter (0.88 lmp qt,
1.06 US qt)
Oil exchanging
capacity
0.9 liter (0.79 lmp qt,
0.95 US qt)
Cooling Type Air cooling
Air cleaner type & No Sponge
Fuel capacity 8.1 liters (1.7 lmp gal,
2.11 Usgal)
Type PD
Float lever 14.8 mm (0.592 in)
Venturi dia. !25 mm (!1 in)
Throttle type PISTON
Type CDI
Ignition timing 15 BTDC/1700rpm
Contact breaker Non-contact point type
Spark plug (NGK) DR-8EA
Spark plug gap 0.6Д0.7 mm
(0.024Д0.028 in)
Battery Capacity 12V8AH
Clutch type CVT
Primary reduction
system Helical gear/spur gear
Secondary reduction
system Chain drive
Primary reduction ratio 2.8-0.95
Secondary reduction
ratio 7.226
Reverse ratio 26.902
FR/RR tire rolling
circumference
1596/1756 mm
(63.84/70.24 in)
Front 20 kPa (0.2 kg/cm2,2.84
psi)
Tire pressure Rear 25 kPa (0.25 kg/cm2,
3.55 psi
Turning Left 44
angle Right 44
Rea
r
Disk brake Drum brake
Brake system type Front Drum brake
Sus
p
ension Fron
t
Swin
g
type Rear Swing arm
Shock Front Swing
type Rear Swing arm
Frame type Steel tube type
Tires
Lubrication System
Engine
Fuel S
y
stem
Carbureto
r
Electrical Equipment
I
g
nition S
y
stem
Damping Device
Moving Device
Power Drive System

1. GENERAL INFORMATION
1-4
ATV 150/125
(MXU 150)
Model No. LA30
ATV Name MXU 150
Overall length 1775 mm (71 in)
Overall width 950 mm (38 in)
Overall height 1040 mm (41.6 in)
Wheel base 1115 mm (44.6 in)
Engine type OHC
Displacement 149 cc (9.1 cu-in)
Fuel Used 92# nonleaded gasoline
Front wheel 87 kg (191.4 lbs)
Dry weight Rear wheel 88 kg (193.6 lbs)
Total 175 kg (385 lbs)
Front wheel 92 kg (202.4 lbs)
Gross weight Rear wheel 93 kg (204.6 lbs)
Total 185 kg (407 lbs)
Front wheel 21*7-10
Rear wheel 22*10-10
Ground clearance 155 mm (6.2 in)
Perform- Breakin
g
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 62 x 49.5
(2.48 x1.98 in)
Compression ratio 9.7:1
Compression pressure 1600 kPa (16 kg/cm2,
227.2 psi)
Open 5.5 BTDC
Intake Close 27.5 ABDC
Open 36 BBDC
Exhaust
Close 4 ATDC
Intake 0.06 mm (0.0024 in)
Valve clearance Exhaust 0.06 mm (0.0024 in)
Idle speed 1700 rpm
Lubrication type Forced
p
ressure &
Wet sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity 1 liter (0.88 lmp qt,
1.06 US qt)
Oil exchanging
capacity
0.9 liter (0.79 lmp qt,
0.95 US qt)
Cooling Type Air cooling
Air cleaner type & No Sponge
Fuel capacity 8.1 liters (1.7 lmp gal,
2.11 Usgal)
Type PD
Piston dia. 14.8 mm (0.592 in)
Venturi dia.(mm) !25 mm (!1 in)
Throttle type PISTON
Type CDI
Ignition timing 15 BTDC/1700rpm
Contact breaker Non-contact point type
Spark plug (NGK) DR-8EA
Spark plug gap 0.6Д0.7 mm
(0.024Д0.028 in)
Battery Capacity 12V8AH
Clutch type CVT
Primary reduction
system Helical gear/spur gear
Secondary reduction
system Chain drive
Primary reduction ratio 2.8-0.95
Secondary reduction
ratio 7.226
Reverse ratio 26.902
FR/RR tire rolling
circumference
1675/1756 mm
(67/70.24 in)
Front 28 Kpa (0.28 kg/cm2,
3.976 psi)
Tire pressure
Rear 28 Kpa (0.28 kg/cm2,
3.976 psi)
Turning Left 40
angle Right 40
Brake s
y
ste
m
Rea
r
Disk brake Drum brake
type Front Drum brake
Sus
p
ension Fron
t
Swin
g
type Rear Swing arm
Shock Front Swing
type Rear Swing arm
Frame type Steel tube pipe
Lubrication System
Tires
Fuel S
y
stem
Carbureto
r
Electrical Equipment
I
g
nition S
y
stem
Damping Device
Power Drive System Moving Device
Engine

1. GENERAL INFORMATION
1-5
ATV 150/125
SERVICE PRECAUTIONS
Make sure to install new gaskets, O-rings,
circlips, cotter pins, etc. when
reassembling.
When tightening bolts or nuts, begin with
larger-diameter to smaller ones at several
times, and tighten to the specified torque
diagonally.
Use genuine parts and lubricants.
When servicing the motorcycle, be sure
to use special tools for removal and
installation.
After disassembly, clean removed parts.
Lubricate sliding surfaces with engine oil
before reassembly.

1. GENERAL INFORMATION
1-6
ATV 150/125
Apply or add designated greases and
lubricants to the specified lubrication
points.
After reassembly, check all parts for
proper tightening and operation.
When two persons work together, pay
attention to the mutual working safety.
Disconnect the battery negative (-)
terminal before operation.
When using a spanner or other tools,
make sure not to damage the motorcycle
surface.
After operation, check all connecting
points, fasteners, and lines for proper
connection and installation.
When connecting the battery, the positive
(+) terminal must be connected first.
After connection, apply grease to the
battery terminals.
Terminal caps shall be installed securely.

1. GENERAL INFORMATION
1-7
ATV 150/125
If the fuse is burned out, find the cause
and repair it. Replace it with a new one
according to the specified capacity.
After operation, terminal caps shall be
installed securely.
When taking out the connector, the lock
on the connector shall be released before
operation.
Hold the connector body when
connecting or disconnecting it.
Do not pull the connector wire.
Check if any connector terminal is
bending, protruding or loose.
Confir
m
Capacity

1. GENERAL INFORMATION
1-8
ATV 150/125
The connector shall be inserted
completely.
If the double connector has a lock,
lock it at the correct position.
Check if there is any loose wire.
Before connecting a terminal, check
for damaged terminal cover or loose
negative terminal.
Check the double connector cover for
proper coverage and installation.
Insert the terminal completely.
Check the terminal cover for proper
coverage.
Do not make the terminal cover opening
face up.
Secure 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.
Sna
pp
in
g
!

1. GENERAL INFORMATION
1-9
ATV 150/125
After clamping, check each wire to make
sure it is secure.
Do not squeeze wires against the weld or
its clamp.
After clamping, check each harness to
make sure that it is not interfering with
any moving or sliding parts.
When fixing the wire harnesses, do not
make it contact the parts which will
generate high heat.
Route wire harnesses to avoid sharp
edges or corners. Avoid the projected
ends of bolts and screws.
Route wire harnesses passing through the
side of bolts and screws. Avoid the
projected ends of bolts and screws.
N
o Contact !

1. GENERAL INFORMATION
1-10
ATV 150/125
Route harnesses so they are neither
pulled tight nor have excessive slack.
Protect wires and harnesses with
electrical tape or tube if they contact a
sharp edge or corner.
When rubber protecting cover is used to
protect the wire harnesses, it shall be
installed securely.
Do not break the sheath of wire.
If a wire or harness is with a broken
sheath, repair by wrapping it with
protective tape or replace it.
When 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
1-11
ATV 150/125
After routing, check that the wire
harnesses are not twisted or kinked.
Wire harnesses routed along with
handlebar should not be pulled tight, have
excessive slack or interfere with adjacent
or surrounding parts in all steering
positions.
When a testing device is used, make sure
to understand the operating methods
thoroughly and operate according to the
operating instructions.
Be careful not to drop any parts.
When 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
1-12
ATV 150/125
Symbols:
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#)
: Note
: Warning
En
g
ine Oil
Grease
Gear Oil

1. GENERAL INFORMATION
1-13
ATV 150/125
TORQUE VALUES
STANDARD TORQUE VALUES
Item Torque
kgf-m (N-m, lbf-ft) Item Torque
kgf-m (N-m, lbf-ft)
5mm bolt and nut
6mm bolt and nut
8mm bolt and nut
10mm bolt and nut
12mm bolt and nut
14mm bolt and nut
0.5 (5, 3.6)
1 (10, 7.2)
2.2 (22, 16)
3.5 (35, 25)
5.5 (55, 40)
7 (70, 50)
4mm screw
5mm screw
6mm screw, SH bolt
6mm flange bolt and nut
8mm flange bolt and nut
10mm flange bolt and nut
0.3 (3, 2.2)
0.4 (4, 2.9)
0.9 (9, 6.5)
1.2 (12, 9)
2.7 (27, 20)
4 (40, 29)
Torque specifications listed below are for important fasteners.
ENGINE
Item Q‘ty Thread dia.
(mm)
Torque
kgf-m (N-m, lbf-ft) Remarks
Stud bolt
Oil filter screen cap
Seat ball stopper bolt
L cover
Cam holder
Tappet ADJ nut
Pivot tensioner
Lifter tensioner
Lifter tensioner
Right crankcase bolt
Driver face
Clutch outer
Balancer shaft nut
Start clutch nut
ACG flywheel
Spark plug
Drain bolt mission
Drain plug
Motor srart
Oil pump
Oil pump sprocket
Head CYL bolt
Drive plate nut
Stator
4
1
1
8
4
2
1
2
1
9
1
1
1
1
1
1
1
1
2
2
2
2
1
4
8
30
14
6
8
6
8
6
6
6
12
12
16
22
14
8
8
12
6
6
6
6
28
5
0.9 (9, 6.5)
1.5 (15, 11)
4.8 (48, 35)
1.2 (12, 8.6)
2 (20, 14)
0.9 (9, 6.5)
1 (10, 7)
1.2 (12, 8.6)
0.4 (4, 2.9)
1 (10, 7)
6 (60, 43)
5.5 (55, 40)
4.5 (45, 32)
9.5 (95, 68)
5.5 (55, 40)
1.5 (15, 11)
1 (10, 7)
2.5 (25, 18)
1 (10, 7)
1 (10, 7)
1 (10, 7)
1 (10, 7)
5.5 (55, 40)
1 (10, 7)
Apply oil
Apply oil
Apply oil
Left threaded
Apply oil, Left threaded

1. GENERAL INFORMATION
1-14
ATV 150/125
ENGINE (Cont’d)
Item Q‘t
y
Thread dia.
(mm)
Torque
k
g
f-
m
(
N-m, lbf-ft
)
Remarks
R cover
Head cover
Cap R cover
Guide star change handle
Sprocket drive plate
Carburetor
Transmission oil check bolt
9
4
1
3
2
2
1
6
6
6
6
6
6
10
1 (10, 7)
1 (10, 7)
1 (10, 7)
1 (10, 7)
1 (10, 7)
1 (10, 7)
1.2 (12, 9)
FRAME
Item Q‘t
y
Thread dia.
(mm)
Torque
k
g
f-
m
(
N-m, lbf-ft
)
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
7 (70, 50)
4.5 (45, 32)
7 (70, 50)
7 (70, 50)
4 (40, 29)
4 (40, 29)
4 (40, 29)
7 (70, 50)
7 (70, 50)
12 (120, 86)
4 (40, 29)
4 (40, 29)
4 (40, 29)
3.5 (35, 25)

1. GENERAL INFORMATION
1-15
ATV 150/125
SPECIAL TOOLS
Tool Name Tool No. Remarks
Flywheel puller E003 Flywheel removal
Lock nut wrench E009 Start clutch nut removal/installation
Lock nut wrench E010 Balancer gear nut removal/installation
Valve adjuster E012 Valve clearance adjustment
Valve spring compressor E040 Cylinder head disassembly/assembly
Oil seal and bearing install E014
Universal holder E017 Clutch outer nut removal/installation
Flywheel holder E021 Flywheel nut removal/installation
Clutch spring compressor E034 Driven pulley clutch removal/installation
Bearing puller E037
Nut wrench F010 Rear axle nut removal/installation

1. GENERAL INFORMATION
1-16
ATV 150/125
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#