DOWNTOWN 125i

By KWANG YANG Motor Co., Ltd.1st Edition, Dec 2009

All rights reserved. Any reproduction orunauthorized use without the written

permission of KWANG YANG Motor Co., Ltd.is expressly prohibited.

T300-SK25AA-A1

DOWNTOWN 125i

PREFACE

This Service Manual describes thetechnical features and servicingprocedures for the KYMCODowntown i.Section 1 contains the precautions forall operations stated in this manual.Read them carefully before anyoperation is started.

Section 2 is the removal/installationprocedures for the frame covers whichare subject to removal/installationfrequency during maintenance andservicing operations.

Section 3 describes the inspection/adjustment procedures, safety rulesand service information for each part,starting from periodic maintenance.

Sections 5 to 12 give instructions fordisassembly, assembly andadjustment of engine parts. Section 13is the AFI system. Section 14 to 15 isthe removal/ installation of chassis.Section 16 to 19 states the testing andmeasuring methods of electricalequipment.

Most sections start with an assemblyor system illustration andtroubleshooting for the section. Thesubsequent pages give detailedprocedures for the section.

KWANG YANG MOTOR CO., LTD.QUALITY TECHNOLOGY DEPT.

EDUCATION SECTION

TABLE OF CONTENTS

GENERAL INFORMATION 1

EXHAUST MUFFLER/FRAMECOVERS

2

INSPECTION/ADJUSTMENT 3

LUBRICATION SYSTEM 4

ENGINE REMOVAL/INSTALLATION 5

CYLINDER HEAD/VALVES 6

CYLINDER/PISTON 7

DRIVE AND DRIVEN PULLEYS/V-BELT

8

FINAL REDUCTION 9

A.C. GENERATOR/STARTERCLUTCH

10

CRANKCASE/CRANKSHAFT 11

COOLING SYSTEM 12

FUEL INJECTION SYSTEM 13STEERING HANDLEBAR/FRONTWHEEL/FRONT BRAKE/FRONTSHOCK ABSORBER/FRONT FORK

14

REAR BRAKE/REAR FORK/REARWHEEL/REAR SHOCK ABSORBER`

15

BATTERY/CHARGING SYSTEM 16

IGNITION SYSTEM 17

STARTING SYSTEM 18

LIGHTS SWITCHES / FUEL PUMP 19

The information and contentsincluded in this manual may bedifferent from the motorcycle in casespecifications are changed.

CH

AS

SIS

ELEC

TRIC

ALE

QU

IPM

EN

TE

NG

INE

1. GENERAL INFORMATION

1-0

DOWNTOWN 125i

1

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GENERAL INFORMATION________________________________________________________________________________

SERIAL NUMBER ------------------------------------------------------------------------------------ 1-1

SPECIFICATION ------------------------------------------------------------------------------------- 1-2

SERVICE PRECAUTIONS------------------------------------------------------------------------- 1-3

TORQUE VALUES ----------------------------------------------------------------------------------- 1-4

SPECIAL TOOLS------------------------------------------------------------------------------------- 1-6

LUBRICATION POINTS ---------------------------------------------------------------------------- 1-7

CABLE & HARNESS ROUTING--------------------------------------------------------------------- 1-8

1

1. GENERAL INFORMATION

1-1

DOWNTOWN 125i

SERIAL NUMBER

Location of Frame Serial Number(inside luggage box)

Location of Vehicle IdentificationNumber (VIN)

Location of Engine Serial Number

1. GENERAL INFORMATION

SPECIFICATIONS

- 2 -

Name DOWNTOWN125i

Model No. SK25AA

Overall length 2200mm

Overall width 800 mm

Overall height 1410 mm

Wheel base 1542 mm

Engine type O.H.C.

Displacement 124.8cc

Fuel Used 92# nonleaded gasoline

Front wheel 68

Net weight (kg) Rear wheel 96

Total 164

Front wheel 70

Gross weight(kg) Rear wheel 104

Total 178

Front wheel 120/80-14

Rear wheel 150/70-13

RR Ground clearance 140 mm

Perform- Braking distance (m) 7.9m/30km/hance Min. turning radius 2600mm

Starting systemStarting motor

Type liquid cooled 4 stroke

Cylinder arrangement Single cylinder

Combustion chamber type Semi-sphere

Valve arrangement O.H.C.4V

Bore x stroke (mm) 54 x 54.5

Compression ratio 11.7:1Compression pressure(kg/cm) 15

Max .horsepower (ps/rpm) 15/8750~9000

Max. torque (kg m/rpm) 1.17/8500~8750

Intake Open 8 BTDC

Port (1mm) Close 31 BTDCtiming Exhaust Open 32 BTDC

(1mm) Close 6 BTDC

Valve Intake 0.10 mm

clearance Exhaust 0.10 mm

Idle speed (rpm) 1850rpm

Lubrication type Forced pressure &Wet sump

Oil pump type Inner/outer rotor type

Oil filter type Full-flow filtration

Oil capacity 1.2 L

Exchanging capacity 1.0 L

Cooling Type Liquid cooling

Tires

En

gin

e

Lu

bricatio

nS

ystem

Air cleaner type & No Paper element, wet

Fuel capacity 12.5 L

Throttle type Butterfly type

Type ECU

Spark plug NGK CR7E

Spark plug gap 0.60.7mm

Battery Capacity 12V10AH

Clutch Type Dry multi-disc clutch

Type Non-stage transmission

Operation Automatic centrifugaltype

Type Two-stage reduction

Reduction 1st 0.83~2.2

ratio 2nd 10.41

Front Caster angle 28

Axle Trail length 140mm

Tire pressure Front 2.0(kg/cm) 1person

Rear 2.25

Turning Left 40

angle Right 40

Brake system Front Disk braketype Rear Disk brake

Front Telescope

Suspensiontype Rear DOUBLE SWING

Frame type PIPE UNDER BONE

Red

uctio

nG

earT

ransm

is-sio

nG

ear

Fu

elS

ystem

Po

wer

Driv

eS

ystem

Electrical

Eq

uip

.

Ign

ition

Sy

stem

Mo

vin

gD

evice

Dam

pin

gD

evice

DOWNTOWN 125i

1. GENERAL INFORMATION

1-3

DOWNTOWN 125i

Symbols:The following symbols represent theservicing methods and cautions included inthis service manual.

: Apply engine oil to thespecified points. (Usedesignated engine oil forlubrication.)

: Apply grease for lubrication.

: Transmission Gear Oil (90#)

: Use special tool.

: Caution

: Warning

Special

Engine Oil

Grease

Gear Oil

1. GENERAL INFORMATION

1-4

DOWNTOWN 125i

TORQUE VALUES

1. GENERAL INFORMATION

1-5

DOWNTOWN 125i

TORQUE VALUESFRAME

1. GENERAL INFORMATION Downtown 125iSPECIAL TOOLS

Tool Name Tool No. Performance Photo

Flywheel Puller A120E00003 A.C. generator flywheel removal

Tappet Adjuster A120E00012 Tappet adjustment

Oil Seal & BearingInstaller

A120E00014 Oil seal & bearing installing

Flywheel Holder A120E00021 A.C. generator flywheel holding

#41 Nut & Fitting A120E00028 Clutch disassembly & assembly

Thread Protector A120E00029 Protecting the crankshaftsthread

Valve Cotter Installer A120E00051 Valve cotter installation

Clutch SpringCompressor

A120E00053 Clutch disassembly & assembly

Shaft Collar Puller A120E00088 Bearing crankcase removal

Shaft Collar Driver A120E00091 Bearing crankcase removal

Shaft Collar Installer A120E00092 Bearing crankcase installation

Bearing Puller A120E00093 Bearing removal

Lock Nut Socket Wrench A120F00002 Steering stem removal orinstallation

Electric Repair Kit A120F00032 Fuel injection system diagnosis

1-6

DOWNTOWN 125i

LUBRICATION POINTSFRAMEThe following is the lubrication points for the frame.Use grease for parts not listed.Apply engine oil or grease to cables and movable parts not specified. It will avoid abnormal noiseand damage the durability of the motorcycle.

Grease

Grease

Front wheel axle &nut Rear wheel axle &nut

Grease

Side stand pivot& Main stand pivot

1. GENERAL INFORMATION

1-7

1. GENERAL INFORMATION

1-8

DOWNTOWN 125i

CABLE & HARNESS ROUTING

Tilt Switch Speedometer

Radiator Filler Cap

Ignition Switch

Horn

Winker RelayHi Beam Relay

Lo Beam Relay

DOWNTOWN 125i

Oil controller

Fuel Pump Relay

Ignition Coil

Output Voltage Connector

Coolant Reserve Tank

1. GENERAL INFORMATION

1-9

2. EXHAUST MUFFLER/FRAME COVERS

2-0

DOWNTOWN 125i

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EXHAUST MUFFLER/FRAME COVERS__________________________________________________________________________________

SCHEMATIC DRAWING ------------------------------------------------- 2- 1SERVICE INFORMATION------------------------------------------------ 2