KYMCO ZX, SCOUT 50 Service Manual

ZX / SCOUT

PREFACE

This Service Manual describes the technical feature.s and servicing
procedures for the KYMCO ZX / SCOUT 50.

In this manual, many illustrations and drawings are used to help
servicemen have better understanding.

Section 2 contains the service precautions for all operations and
troubleshooting stated in this manual. Read them carefully before starting
any operation.

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

Sections 4 through 16 give instructions for disassembly, assembly and
inspection of lubrication system, engine, fuel system and electrical
equipment.

Section 17 is the maintenance and inspection directions for the evaporative/
exhaust emission control system. 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

MARCH 2000

1. SPECIFICATIONS

1-0

ZX / SCOUT

1

TABLE OF CONTENTS

SPECIFICATIONS.................................................................................. 1

GENERAL INFORMATION .................................................................. 2

INSPECTION/ADJUSTMENT............................................................... 3

LUBRICATION SYSTEM ....................................................................... 4

ENGINE REMOVAL/INSTALLATION................................................. 5

CYLINDER HEAD/CYLINDER/PISTON.............................................. 6

A.C. GENERATOR ................................................................................. 7

KICK STARTER/DRIVE PULLEY/CLUTCH/DRIVEN PULLEY....... 8

FINAL REDUCTION............................................................................... 9

CRANKCASE/CRANKSHAFT...............................................................10

CARBURETOR .......................................................................................11

FRAME COVERS....................................................................................12

STEERING HANDLEBAR/FRONT WHEEL/FRONT BRAKE/

FRONT SHOCK ABSORBER/FRONT FORK......................................13

REAR WHEEL/REAR BRAKE/REAR SHOCK ABSORBER ..............14

ELECTRICAL EQUIPMENT.................................................................15

INSTRUMENT/SWITCHES/LIGHTS....................................................16

EVAPORATIVE/EXHAUST EMISSION CONTRAL SYSTEM ...........17

1

1. SPECIFICATIONS

1-1

ZX 50

SPECIFICATIONS

Name & Model SC10AS
Overall length (mm) 1792
Overall width (mm) 690
Overall height (mm) 1053
Wheel base (mm) 1225
Engine type Air cooled 2-stroke
Displacement (cc) 49.4 cc

Net weight (kg)

92.5

Seating capacity 2 riders (110kg)

Gross weight(kg)

150

Front wheel

120/70-12

Tires

Rear wheel

120/70-12

Ground clearance (mm) 170
Braking distance (m)

(Initial speed Km/h)

7m (30km/h)

Min. turning radius (mm) 1940
Starting system

Starting motor &

kick starter

Fuel type

Gasoline, 2-stroke

motor oil
Cylinder arrangement Single cylinder, flat
Combustion chamber type Semi -sphere
Valve arrangement Reed valve & piston
Bore x stroke (mm) 39 x 41.4
Compression ratio 7.3 : 1
Compression pressur e

(kg/cm ² rpm)

11.5kg/cm ²

Max. output (kw/rpm) 3.75/7000kw/rpm
Max. torque (kg-m/rpm) 4.5/6500 kg m/rpm
Open Automatic controlled

Intake

Close Automatic controlled

Port Open 
timing

Exhaust

Close 

Open 

Scavenge

Close 

Idle speed (rpm) 2100±100
Lubrication type Separate type
Oil pump type Plunger type

Oil filter type Full-flow filtration

Lubrication oil capacity (liter) 0.80
Air cleaner type & No. Wet, single
Fuel capacity (liter) 4.9
Type Plunger type
Carburetor Piston dia. (mm) 
Venturi dia. (mm) 14

Ignition system type

CDI electromagnetic

Ignition

Ignition timing F mark 15.5°±2°BTDC/2000rpm

Spark

NGK BR8HSA

plug

ND

Spark plug gap (mm) 0.6 0.7
Battery capacity 12V3AH

Power to transmission gear

Power-transmission

gear-clutch

Reduction ratio of power to
transmission



Clutch type Dry multi-disc clutch
Transmission gear operation

type

Automatic centrifugal
type

Transmission ratio 1 spe

ed



Reduction Type Two-stage reduction
gear 1st reduction ratio 
2nd reduction ratio



Transmission gear type Non-stage transmission

Tire pressure

Front wheel

1.50 1.75

(kg/cm ²)

Rear wheel 1.75 2.25

Turning angle Right & left 45°

Brake system

Front wheel

Expanding/hydraulic

type

Rear wheel

Expanding

Suspension

Front wheel

Telescope

type

Rear wheel

Unit swing

Shock absorber

Front wheel

Telescope

type

Rear wheel

Unit swing

Frame type Pipe under bone

CO 4.5% Exhaust

emission

concentration

HC 7000ppm Max

2. GENERAL INFORMATION

2-0

ZX / SCOUT

1

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

GENERAL INFORMATION

__________________________________________________________________________________

ENGINE SERIAL NUMBER/IDENTIFICATION............................2- 1

SERVICE PRECAUTIONS ............................................................2- 2

SERVICE INFORMATION ............................................................2- 6

TORQUE VALUES........................................................................2- 8

SPECIAL TOOLS ..........................................................................2- 9

LUBRICATION POINTS...............................................................2-11

WIRING DIAGRAM......................................................................2-12

CABLE & HARNESS ROUTING...................................................2-13

TROUBLESHOOTING ..................................................................2-17

2

2. GENERAL INFORMATION

2-1

ZX / SCOUT

ENGINE SERIAL NUMBER/IDENTIFICATION

Location of Engine Serial Number

2. GENERAL INFORMATION

2-2

ZX / SCOUT

SERVICE PRECAUTIONS

n Make sure to install new gaskets, O-rings,

circlips, cotter pins, etc. when reassembling.

n When tightening bolts or nuts, begin with

larger-diameter to smaller ones at several
times, and tighten to the specified torque
diagonally.

n Use genuine parts and lubricants.

n When servicing the motorcycle, be sure to use

special tools for removal and installation.

n After disassembly, clean removed parts.

Lubricate sliding surfaces with engine oil
before reassembly.

n Apply or add designated greases and

lubricants to the specified lubrication points.

n After reassembly, check all parts for proper

tightening and operation.

n When two persons work together, pay

attention to the mutual working safety.

n Disconnect the battery negative (-) terminal

before operation.

n When using a spanner or other tools, make

sure not to damage the motorcycle surface.

n After operation, check all connecting points,

fasteners, and lines for proper connection and
installation.

n When connecting the battery, the positive (+)

terminal must be connected first.

n After connection, apply grease to the battery

terminals.

n Terminal caps shall be installed securely.

n If the fuse is burned out, find the cause and

repair it. Replace it with a new one according

2. GENERAL INFORMATION

2-3

ZX / SCOUT

to the specified capacity.

n After operation, terminal caps shall be installed

securely.

n When taking out the connector, the lock on

the connector shall be released before
operation.

n Hold the connector body when connecting or

disconnecting it.

n Do not pull the connector wire.

n Check if any connector terminal is bending,

protruding or loose.

n The connector shall be inserted completely.

n If the double connector has a lock, lock it

at the correct position.

n Check if there is any loose wire.

n Before connecting a terminal, check for

damaged terminal cover or loose negative
terminal.

n Check the double connector cover for proper

coverage and installation.

n Insert the terminal completely.
n Check the terminal cover for proper coverage.
n Do not make the terminal cover opening face

up.

n 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.

n After clamping, check each wire to make sure

it is secure.

Easy confirm

2. GENERAL INFORMATION

2-4

ZX / SCOUT

n Do not squeeze wires against the weld or its

clamp.

n After clamping, check each harness to make

sure that it is not interfering with any moving or
sliding parts.

n When fixing the wire harnesses, do not make it

contact the parts which will generate high heat.

n Route wire harnesses to avoid sharp edges or

corners. Avoid the projected ends of bolts
and screws.

n Route wire harnesses passing through the side

of bolts and screws. Avoid the projected
ends of bolts and screws.

n Route harnesses so they are neither pulled

tight nor have excessive slack.

n Protect wires and harnesses with electrical

tape or tube if they contact a sharp edge or
corner.

n When rubber protecting cover is used to

protect the wire harnesses, it shall be installed
securely.

n Do not break the sheath of wire.
n If a wire or harness is with a broken sheath,

repair by wrapping it with protective tape or
replace it.

n When installing other parts, do not press or

squeeze the wires.

n After routing, check that the wire harnesses

are not twisted or kinked.

Don’t touch

2. GENERAL INFORMATION

2-5

ZX / SCOUT

n 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.

n When a testing device is used, make sure to

understand the operating methods thoroughly
and operate according to the operating
instructions.

n Be careful not to drop any parts.

n When rust is found on a terminal, remove the

rust with sand paper or equivalent before
connecting.

n 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.

: Use special tool.

: Caution

: Warning

(ð12-3) : Refer to page 12-3.

Engine Oil

Grease

Special

*

Remove the rest

2. GENERAL INFORMATION

2-6

ZX / SCOUT

SERVICE INFORMATION

ENGINE

Standard (mm) Service Limit (mm)

Item SC10AS SC10AS

Cylinder head warpage  0.10
Piston O.D.(5mm from bottom of piston skirt) 38.955 38.970 38.90
Cylinder-to- piston clearance 0.10
Piston pin hole I.D. 12.002 12.008 12.03
Piston pin O.D. 11.994 12.0 11.98
Piston -to-piston pin clearance ← ←
Piston ring end gap (top/second) 0.10 0.25 0.40
Connecting rod small end I.D. 17.005 17.017 17.03
Cylinder bore 39.039.025 39.05
Drive belt width 18 17
Drive pulley collar O.D. 20.01 20.025 ←
Movable drive face ID. 20.035 20.085 19.97
Weight roller O.D. 13.0 12.4
Clutch outer I.D. 107 107.2 107.5
Driven face spring free length 87.9 82.6
Driven face O.D. ← ←
Movable driven face I.D. ← ←
Connecting rod big end side clearance ← ←
Connecting rod big end radial clearance ← ←
Crankshaft runout A/B  ←

CARBURETOR

SC10AS
Venturi dia. 14mm
Identification number 014A
Float level 5.0mm
Main jet #80
Slow jet #35
Air screw opening 1 ±¼
Idle speed 2100±100rpm
Throttle grip free play 2 6mm
Jet needle clip notch 1st notch

2. GENERAL INFORMATION

2-7

ZX / SCOUT

FRAME

Standard (mm) Service Limit (mm)

Item SC10AS SC10AS

Axle shaft runout  0.2

Radial

Front wheel rim runout

Axial
Front shock absorber spring free length 200.0 182.8
Rear wheel rim runout 2.0
Brake drum I.D. Front/rear 110 111
Brake lining thickness Front/rear 4.0/4.0 2.0/2.0
Brake disk runout Front/rear  0.30
Rear shock absorber spring free length 235.7 218.7

ELECTRICAL EQUIPMENT

SC10AS

Capacity 12V3AH

Voltag e 13.0 13.2V

Charging Standard 0.4A/5H

Battery

current Quick 4A/0.5H

Spark plug (NGK) BR8HSA

Spark plug gap 0.6 0.7mm

Primary coil 0.153 0.187Ω

Secondary coil
(with plug cap)

6.99 10.21KΩ

Ignition coil resistance

Secondary coil
(without plug cap)

3.24 3.96KΩ

Pulser coil resistance (20 ) 80 160Ω

Ignition timing 15.5°±2°BTDC/2000rpm

2. GENERAL INFORMATION

2-8

ZX / SCOUT

TORQUE VALUES

ENGINE

Item Thread dia. (mm)

Torque (kg

-m)

Remarks

Cylinder head bolt
Clutch drive plate nut
Clutch outer nut
Drive face nut
Oil check bolt
Engine mounting bolt
Engine hanger bracket bolt
Exhaust muffler joint lock nut
Exhaust muffler lock bolt
Spark plug

BF7x115

10
NH10
NH12

10

BF10x95
BF10x50

NC6mm

BF8x35

1.5 1.7

3.5 4.0

3.5 4.5

5.0 6.0

1.0 1.5

4.5 5.5

3.5 4.5

1.0 1.4

3.0 3.6

1.1 1.7

(cold)

(cold)

FRAME

Item Thread dia. (mm)

Torque (kg

-m)

Remarks

Handlebar lock nut
Steering stem lock nut
Steering top cone race
Front axle nut
Rear axle nut
Rear brake arm bolt
Front shock absorber:
upper mount bolt
lower mount bolt
hex bolt
Front damper nut
Front pivot arm bolt
Rear shock absorber:
upper mount bolt
lower mount bolt
lower joint nut

10

25.4

25.4
12
16

8

8

10

8
8

4.5 5.0

8.0 12.0

0.5 1.3

5.0 7.0

11.0 13.0

3.3

3.3

1.5 3.0

1.5 3.0

3.5 4.5

2.4 3.0

1.5 2.5

Flange bolt/U-nut

Flange U-nut
Flange U-nut
Flange nut

Flange bolt/U-nut
Cross head
Apply locking agent

Flange screw/U-nut

Flange nut

Torque specifications listed above are for important fasteners. Others should be tightened to standard
torque values below.

STANDARD TORQUE VALUES SH bolt: 8mm Flange 6mm bolt

Item Torque (kg

-m)

Item Torque (kg

-m)

5mm bolt, nut
6mm bolt, nut
8mm bolt, nut
10mm bolt, nut
12mm bolt, nut

0.45 0.6

0.8 1.2

1.8 2.5

3.0 4.0

5.0 6.0

5mm screw
6mm screw, SH bolt
6mm flange bolt, nut
8mm flange bolt, nut
10mm flange bolt, nut

0.35 0.5

0.7 1.1

1.0 1.4

2.4 3.0

3.5 4.5

2. GENERAL INFORMATION

2-9

ZX / SCOUT

SPECIAL TOOLS

Tool Name Tool No. Remarks

Universal bearing puller E030 Crankshaft bearing removal
Lock nut socket wrench F001 Top cone race holding
Lock nut wrench, F002 Stem lock nut tightening
Crankcase puller E026 Crankcase disassembly
Bearing remover set, 12mm

(Spindle assy, 12mm)
(Remover weight)

E020

Drive shaft bearing removal/installation

Bearing remover set, 15mm
(Spindle assy, 15mm)
(Remover head, 15mm)
(Remover shaft, 15mm)

E018

Drive shaft bearing removal/installation

Bearing outer driver, 28x30mm E014 Bearing installation
Clutch spring compressor E027 Driven pulley disassembly/assembly

Crankcase assembly collar E023

Driven shaft, crankshaft & crankcase

assembly
Crankcase assembly tool E024 Crankshaft & crankcase assembly
Ball race remover F005 Steering stem bearing races
Rear shock absorber compressor F004 Rear shock absorber disassembly/assembly
Universal holder E017 Flywheel holding
Flywheel puller E001 Flywheel removal

Bearing outer driver, 32x35mm E014

Drive shaft bearing installation

Final shaft bearing installation

Bearing outer driver, 37x40mm E014

Drive shaft bearing installation Final shaft

bearing installation Crankshaft bearing

installation

Universal bearing puller E030 Crankshaft bearing removal

LUBRICATION POINTS

2. GENERAL INFORMATION

2-10

ZX / SCOUT

ENGINE

NO.

Lubrication Points Lubricant Remarks
1 Crankcase sliding & movable parts JASO-FC or API-TC
2 Cylinder movable parts JASO-FC or API-TC
3 Transmission gear (final gear) SAE-90#
4 Kick starter spindle bushing Grease
5 Drive pulley movable parts Grease
6 Starter pinion movable parts Grease

FRAME
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.

SC10AS WIRING DIAGRAM

Front/Rear Brake Lever

Seat Lock

Rear Wheel Bearing

Throttle Cable

Main Stand Pivot

Grease

Engine Oil

Grease

Engine Oil

Speedometer Gear/

Brake Cam/Front
Shock Absorber
Lower Mount
Bushings/Pivot

Grease

Grease

Grease

Grease

Engine Oil

Rear Brake Cable

Brake Cam/

Anchor Pin

2. GENERAL INFORMATION

2-11

ZX / SCOUT

CABLE & HARNESS ROUTING

2. GENERAL INFORMATION

2-12

ZX / SCOUT

Front Brake Reservoir

Rear Brake Cable

Throttle Cable

Ignition Switch

Regulator/Rectifier

Front Brake Fluid Tube

Resistor

Front Stop Switch Wire

Rear Stop Switch Wire

Speedometer Cable

Speedometer Cable

Front Brake Fluid Tube

Horn

2. GENERAL INFORMATION

2-13

ZX / SCOUT

Ignition Coil

Fuel Unit

Wire Harness

Rear Brake Cable

Throttle Cable

Front Brake Fluid Tube

Speedometer Cable

Speedometer Cable

Front Brake Fluid Tube

2. GENERAL INFORMATION

2-14

ZX / SCOUT

Fuel Filter

Oil Tank Cap

Starter Relay

CDI Unit

Battery

Wire Harness

Ignition Coil

Oil Tube

2. GENERAL INFORMATION

2-15

ZX / SCOUT

TROUBLESHOOTING

Vacuum Tee

Oil Pump

Ignition Coil

Oil Tube

Fuel Unit

Fuel Tank Cap

2. GENERAL INFORMATION

2-16

ZX / SCOUT

ENGINE WILL NOT START OR IS HARD TO START

• Empty fuel tank
‚ Clogged float valve
ƒ Clogged fuel filter
„ Faulty auto fuel valve

• Faulty spark plug
‚ Fouled spark plug
ƒ Faulty CDI unit
„ Faulty A.C. generator
… Broken or shorted ignition coil
† Broken or shorted exciter coil
‡Faulty ignition switch

• Burned or worn cylinder

piston

‚ Faulty reed valve
ƒ Blown cylinder head gasket
„ Leaking crankcase
… Faulty crankcase oil seal

• Incorrectly adjusted idle speed
‚ Air leaking through intake

pipe

ƒ Incorrect ignition timing

• Flooded carburetor
‚ Throttle valve excessively

open

• Faulty auto bystarter

ENGINE STOPS IMMEDIATELY AFTER IT STARTS

Inspection/Adjustment Symptom Probable Cause

Check if fuel reaches

carburetor by loosening
drain screw.

Remove spark plug and

install it into spark plug
cap to test spark by
connecting it to engine
ground.

Inspection/Adjustment Symptom Probable Cause

Fuel reaches

carburetor

Spark jumps

Dry spark plug

Not clogged

Normal

compression

Engine does not

fire

Fuel does not

reach carburetor

Weak or no spark

Wet spark plug

Clogged

Low or no

compression

Engine fires but

does not start

Test cylinder

compression.

Remove spark plug and

inspect again.

Wait for

30 minutes and

then remove the
carbu-retor auto choke
circuit hose and blow
the hose with mouth.

Start engine by

follow-ing normal
starting procedure.

2. GENERAL INFORMATION

2-17

ZX / SCOUT

• Empty fuel tank
‚ Clogged float valve
ƒ Clogged fuel filter
„ Faulty auto fuel valve

• Fouled spark plug
‚ Incorrect heat range plug

• Fouled spark plug
‚ Faulty CDI unit
ƒ Faulty A.C. generator
„ Faulty ignition coil
… Broken or shorted high

tension wire

† Faulty ignition switch

• Worn cylinder and piston rings
‚ Blown cylinder head gasket
ƒ Flaws in cylinder head
„ Faulty reed valve
… Seized piston

• Clogged carburetor jets

• Faulty CDI unit or A.C.

generator

‚ A.C.G. flywheel not aligned

• Mixture too rich (turn screw

out)

‚ Mixture too lean (turn screw

in)

Check if fuel reaches

carburetor by loosening
drain screw.

Fuel reaches

carburetor

Good spark

Remove spark plug and

install it into spark plug
cap to test spark by
connecting it to engine
ground.

Correct timing

Correctly adjusted

Plug not fouled or

discolored

Normal

compression

Not Clogged

Fuel does not

reach carburetor

Weak or inter

-

mittent spark

Incorrect timing

Incorrectly adjusted

Plug fouled or

discolored

Abnormal

compression

Clogged

Inspection/Adjustment

Symptom Probable Cause

Test cylinder

compression (using a
compression gauge).

Check carburetor for
clogging.

Check carburetor
gasket for air leaks.

Check ignition timing.

Check carburetor air
screw adjustment.

Remove spark plug and

install it into spark plug
cap to test spark by
connecting it to engine
ground.

2. GENERAL INFORMATION

2-18

ZX / SCOUT

• Carburetor not securely
tightened

‚ Faulty intake manifold gasket
ƒ Deformed or broken

carburetor O-ring

• Broken cable

‚ Dirty auto bystarter
ƒ Faulty auto bystarter

• Faulty auto bystarter

ENGINE LACKS POWER

Inspection/Adjustment Symptom

Probable Cause

No air leak

Not clogged

Clogged

Air leaks

Clogged

Not Clo gged

Connect auto bystarter

wire to battery. Wait for
5 minutes, then connect
a hose to fuel enriching
circuit and then blow
the hose with mouth.

Remove auto bystarter

connecting wire and
check if bypass fuel line
is clogged.

Start engine and

accelerate lightly for
observation.

2. GENERAL INFORMATION

2-19

ZX / SCOUT

• Clogged air cleaner

‚ Clogged fuel filter
ƒ Clogged exhaust muffler
„ Faulty auto bystarter

• Faulty CDI unit

‚ Faulty A.C. generator

• Worn cylinder and piston rings

‚ Blown cylinder head gasket
ƒ Faulty reed valve

• Clogged carburetor jets

• Fouled spark plug

‚ Incorrect heat range plug

• Mixture too lean

‚ Poor quality fuel
ƒ Excessive carbon build -up in

combustion chamber

„ Ignition timing too early

• Excessive carbon build -up in

combustion chamber

‚ Poor quality fuel
ƒ Clutch slipping
„ Mixture too lean

POOR PERFORMANCE (ESPECIALLY AT IDLE AND LOW SPEEDS)

Engine speed

increases

Engine overheats

Correct timing

Inspection/Adjustment

Engine does not

knock

Symptom

Plug not fou

led or

discolored

Probable Cause

Normal

compression

Not Clogged

Engine speed does

not increase
sufficiently

Engine does not

overheats

Incorrect timing

Engine knocks

Plug fouled or

discolored

Abnormal

compression

Clogged

Check ignition timing

(using a timing light).

Rapidly accelerate or
run at high speed

Test cylinder

compression (using a
compression gauge)

Check carburetor for
clogging

Remove spark plug and
inspect

Check if engine
overheats

2. GENERAL INFORMATION

2-20

ZX / SCOUT

• Faulty CDI unit

‚ Faulty A.C. generator

• Mixture too rich (turn screw

out)

‚ Mixture too lean (turn screw

in)

• Carburetor not securely
tightened

‚ Faulty intake manifold gasket
ƒ Deformed carburetor O-ring

• Faulty or fouled spark plug

‚ Faulty CDI unit
ƒ Faulty A.C. generator
„ Faul ty ignition coil
… Broken or shorted high

tension wire

† Faulty ignition switch

• Broken auto bystarter wire

‚ Faulty auto bystarter

POOR PERFORMANCE (AT HIGH SPEED)

Clogged Not clogged

Inspection/Adjustment Symptom Probable Cause

Check ignition timing.

Remove spark plug and

install it into spark plug
cap to test spark by
connecting it to engine
ground.

Check ignition timing.

Connect auto bystarter

wire to battery. Wait for
5 minutes, then connect
a hose to fuel enriching
circuit and then blow
the hose with mouth.

Remove auto bystarter

connecting wire and
check if bypass fuel line
is clogged.

Check carburetor
gasket for air leaks.

Check carburetor air
screw adjustment.

Correct timing

Incorrect timin g

Correctly adjusted

Incorrectly adjusted

No air leak

Air leaks

Good spark

Weak or inter

-

mittent spark

Not clogged

Clogged

2. GENERAL INFORMATION

2-21

ZX / SCOUT

• Faulty CDI unit

‚ Loose A.C.G. stator
ƒ Faulty A.C. generator

• Empty fuel tank

‚ Clogged fuel tube or filter
ƒ Clogged charcoal canister

• Clean and unclog

• Broken auto bystarter wire

‚ Faulty auto bystarter

• Faulty auto bystarter

CLUTCH, DRIVE AND DRIVEN PULLEYS

• Worn or slipping drive belt
‚ Broken ramp plate
ƒ Broken driven face spring
„ Separated clutch lining

Clogged Not clogged

Engine starts but
motor-cycle does not

Symptom

Probable Cause

Connect auto bystarter

wire to battery. Wait for
5 minutes, then connect
a hose to fuel enriching
circuit and then blow
the hose with mouth.

Remove auto bystarter

connecting wire and
check if bypass fuel line
is clogged.

Check carburetor jets
for clogging.

Check auto fuel valve
for fuel supply.

Correct timing

Incorrect timing

Fuel flows freely Fuel flow restricted

Not clogged

Clogged

Not clogged Clogged

2. GENERAL INFORMATION

2-22

ZX / SCOUT

… Damaged driven pulley shaft splines
† Damaged final gear
‡ Seized final gear

• Broken shoe spring
‚ Clutch outer and clutch weight stuck
ƒSeized pivot

• Worn or slipping drive belt
‚ Worn weight rollers
ƒ Seized drive pulley bearings
„ Weak driven face spring
… Worn or seized driven pulley bearings

• Worn or slipping drive belt
‚ Worn weight rollers
ƒ Worn or seized driven pulley bearings

• Oil or grease fouled drive belt
‚ Worn drive belt
ƒ Weak driven face spring
„ Worn or seized driven pulley bearings

STEERING HANDLEBAR DOES NOT TRACK STRAIGHT

(Front and rear tire pressures are normal)

• Steering stem nut too tight
‚ Broken steering steel balls

• Excessive wheel bearing play
‚ Bent rim
ƒ Loose axle nut

• Misaligned front and rear wheels
‚ Bent front fork

POOR SUSPENSION PERFORMANCE

(Front and rear tire pressures are normal)

• Weak shock spring
‚ Excessive load

Engine lacks power at

start of a grade (poor

slope performance)

Steering is heavy

Suspension is too soft

Front or rear wheel is

wobbling

Symptom

Symptom

Probable Cause

Probable Cause

Engine lacks power at

high speed

There is abnormal noise
or smell while running

Motorcycle creeps or

engine starts but soon
stops or seems to rush
out (Rear wheel rotates
when engine idles)

Steering handlebar pulls

to one side

2. GENERAL INFORMATION

2-23

ZX / SCOUT

ƒ Shock damper oil leaking

• Bent fork tube or shock rod
‚ Fork slid er and tube binding

• Fork tube and spring binding
‚ Fork slider and tube binding

POOR BRAKE PERFORMANCE

(Adjust brake according to standards)

• Worn brake linings
‚ Worn brake cam contacting area on

brake shoes

ƒ Worn brake cam
„ Worn brake drum

• Worn brake linings
‚ Foreign matter on brake linings
ƒ Rough brake drum contacting area

• Sluggish or elongated brake cables
‚ Brake shoes improperly contact

brake drum

ƒ Water and mud in brake system
„ Oil or grease on brake linings

• Faulty brake master cylinder
‚ Faulty brake caliper
ƒ Oil or grease on brake disk
„ Deformed brake disk
… Leaking brake fluid tube

OIL METER

1. Motor oil indicator light does not come on when there is no motor oil (Ignition switch ON)
Inspection/Adjustment Symptom Probable Cause

Brake squeaks

Symptom

Probable Cause

Suspension is too hard

Suspension is noisy

Brake performance is

poor

Index mark on brake

panel aligns with wear

indicator arrow

Expanding

Brake

Hydraul

ic

Brake

2. GENERAL INFORMATION

2-24

ZX / SCOUT

Faulty

• Burned out fuse
‚ Weak or dead battery
ƒ Faulty ignition switch

„ Loose or disconnected

connector

… Broken wire harness

•Burned out bulb

• Loose wire connector
‚ Broken wire harness
ƒ Incorrectly connected wire

• Faulty float
‚ Broken or shorted wire in

meter

2. Motor oil is sufficient but the indicator light remains on (Ignition switch ON)

• Loose or disconnected

connector

‚ Broken wire harness
ƒ Incorrectly connected wire

• Faulty float
‚ Broken or shorted wire in

meter

• Damaged oil tank
‚ Foreign matters in oil tank

FUEL GAUGE

1. Pointer does not register correctly (Ignition switch ON)

• Burned out fuse
‚ Weak or dead battery
ƒ Faulty ignition switch

Inspection/Adjustment Symptom

Inspection/Adjustment Symptom Probable Cause

Signals operate

properly

Signals dim, remain

on or don‘t operate

Signals operate

properly

Signals dim, remain

on or don‘t operate

Bulb lights Bulb does not light

Good

Faulty

Remov

e oil meter and

check operation of
indicator light by moving
float

Check connectors for
proper connection.

Good

Probable Cause

Good

Faulty

Remove oil meter and

check operation of
indicator light by moving
float

Check connectors for
proper operation.

Connect indicator light

bulb to battery for bulb
inspection.

Check battery circuit by
operating turn signals.

Good

Faulty

Check battery circuit by

operating turn signals.

Float up = Light off

Float down = Light on

Float up = Light off

Float down = Light on

2. GENERAL INFORMATION

2-25

ZX / SCOUT

„ Loose or disconnected

connector

… Broken wire harness

• Faulty float

• Broken or shorted fuel unit

wire

• Loose or disconnected

connector

‚ Incorrectly connected

connector

• Broken or shorted wire in

fuel gauge

2. Pointer fluctuates or swings (Ignition switch ON)

• Burned out fuse
‚ Weak or dead battery
ƒ Faulty ignition switch
„ Loose or disconnected

connector

… Broken wire harness

• Poor contact in fuel unit

• Insufficient damping oil in

fuel gauge

• Loose or disconnected
connector

• Broken or shorted wire in

fuel gauge

STARTER MOTOR

1. Starter motor won‘t turn

• Burned out fuse
‚ Weak or dead battery
ƒ Faulty stop switch
„ Loose or disconnected

connector

… Broken or shorted ignition

Inspection/Adjustment

Symptom

Inspection/Adjustment Symptom

Stoplight does not

come on

Stoplight comes on

Signals operate

properly

Signals

dim, remain

on or don‘t operate

Pointer does not

move

Pointer does not

move

Good

Good

Pointer moves

Pointer moves

Pointer moves

Pointer does not

move in

accord

-

ance with

Probable Cause

Faulty

Faulty

Pointer does not

move

Pointer moves in

accordance with
float

Probable Cause

Check operation of

stop switch by
applying brake.

Check battery circuit

by operating turn
signals.

Remove fuel unit and

check operation of
pointer by moving float
up and down.

Check operation of

pointer by opening and
shorting fuel unit
terminal on wire
harness side.

Check connectors for
proper connection.

Chec

k operation of

starter relay by

Remove fuel unit and

check operation of
pointer by moving float
up and down.

Check battery circuit by

operating turn signals
and horn.

Move float up and down

rapidly (1 round /sec.)
to check the operation
of pointer.

Check connectors for
proper connection.

2. GENERAL INFORMATION

2-26

ZX / SCOUT

switch wire

• Faulty or weak battery

• Poor starter button connection
‚ Faulty starter relay
ƒ Loose or disconnected

connector

• Faulty starter motor

• Faulty wire harness

2. Starter motor turns slowly or idles

• Weak or dead battery

• Loose or disconnected

connector

‚ Faulty starter relay

• Seized cylinder

• Broken or shorted starter

motor cable

‚ Faulty starter pinion

3. Starter motor does not stop turning

• Faulty starter pinion

• Starter relay shorted or stuc k

closed

Inspection/Adjustment

Inspection/Adjustment

Symptom

Symptom

Signals o

perate

properly

Signals operate

properly

Signals dim, remain

on or don‘t operate

S

ignal

s dim, remain

on or don‘t operate

Starter motor turns

Turns easily

Not stopped

Starter does not

Hard to turn

Stopped

Relay operates

properly

Starter motor

turns slowly

Probable Cause

Probable Cause

Relay does not

operate

Starter motor

turns normally

Check battery circuit

by operating turn
signals.

Turn ignition

switch

OFF.

Connect starter

motor directly to
battery.

Rotate crankshaft.

3. INSPECTION/ADJUSTMENT

3-0

ZX /SCOUT 50

3

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

INSPECTION/ADJUSTMENT

__________________________________________________________________________________

INSPECTION AND MAINTENANCE SCHEDULE........................3- 1

BRAKE SYSTEM...........................................................................3- 4

MOVING DEVICE.........................................................................3- 5

DAMPING DEVICE.......................................................................3- 6

POWER DRIVE SYSTEM .............................................................3- 6

ELECTRICAL EQUIPMENT ..........................................................3- 7

ENGINE.........................................................................................3- 8

OTHERS........................................................................................3- 11

3

3. INSPECTION/ADJUSTMENT

3-1

ZX /SCOUT 50

INSPECTION AND MAINTENANCE SCHEDULE

(Note) 1. means time for inspection.

2. means regular replacement for the specified parts.
This inspection and maintenance schedule is based upon average riding conditions. Machines

subjected to serve use, or ridden in unusually dusty areas, require more frequent servicing.

Frequency

Inspection & Maintenance Item

Preride

1st

month

Every
6
month
s

Every

12

months

Judgment Standards Remarks

Check for looseness and

vertical play

Steering
handlebar

Operating performance
Right/left turning angle

Suspension

Damage
Check for front fork

pivot installation

Check
steering
stem

Front
fork

Check front fork pivot
for looseness and
abnormal noise

Check

steering
stem

Front/rear brake lever
free play

Free play:
10 20mm

Brake lever operation

Brake
Lever

Brake performance

Lever/
Cable

Looseness, abnormal
noise and damage

Brake
System

Drum-to-lining
clearance

Brake shoe and lining
wear

Indi cator
type

Brake
drum/
shoe

Brake drum wear and
damage

Standard:
Front: 110 mm
Rear : 110 mm

Service Limits:
Front: 111 mm
Rear : 111 mm

Moving
Device

Tire Tire pressure

Front Rear

1

rider

1.50

kg/cm²

1.75

kg/cm²

Tire
Size

120/70-12 120/70-1

2

3. INSPECTION/ADJUSTMENT

3-2

ZX /SCOUT 50

Frequency

Inspection & Maintenance Item

Preride

1st

month

Every
6
month
s

Every

12

months

Judgment Standards Remarks

Tire crack and damage

Tire groove and
abnormal wear

Groove Depth:
Front: 0.8mm
Rear : 0.8mm

Imbedded objects,
gravel, etc.

Moving
Device

Motor­cycle

Axle nut looseness

Torque Values:
Front axle nut

5.0 7.0kg-m
Rear axle nut

11.0 13.0kg-m

Axle nut
torque

Check wheel rim, rim

edge and spoke plate for

damage

Rim runout at rim end:

Front: Axial 2.0mm

Radial 2.0mm

Rear: Axial 2.0mm

Radial 2.0mm

Check front wheel
bear-ing for excessive
play and abnormal noise

Check front wheel
bear-ing for excessive
play and abnormal noise

Frame
Spring

Damage

Shock
spring
free
length

Suspen -si
on arm

Connecting parts
loose-ness and arm
damage

Shock

Oil leakage and damage

Damping
Device

absorber

Assembly parts
loose-ness abnormal
noise

Power

Clutch Operation

Drive
System

Transmis­sion case

Oil leakage and oil level

Oil level:
Oil check bolt hole
at lower hole edge

Rear wheel
transmis­sion case

Ignition
device

Spark plug condition

Plug gap: 0.60.7mm

3. INSPECTION/ADJUSTMENT

3-3

ZX /SCOUT 50

Electrical
Equipment

Battery Terminal connection

Wires

Loose connection and
damage

Frequency

Inspection & Maintenance Item

Preride

1st

month

Every
6
month
s

Every

12

months

Judgment Standards Remarks

Performance and abnormal
noise

Body

Conditions at low and high
speeds

Exhaust smoke
Air cleaner

Oil quality and quantity

r Oil level indicator
Indicator light comes on
when oil is insufficient

Engine

Oil leakage
Oil level

Lubrica­tion
system

Check oil filter for clogging
Fuel leakage
Carburetor, throttle valve and

auto bystarter
Check fuel filter for clogging

Fuel level

Fuel
System

Fuel tube replacement

Every 4 years

Operation

Lights & Winker

Winking action, dirt and
damage

Buzzer &
Steering Lock

Operation

Rearview Mirror

& Reflector

Rearview mirror position

Rearview
Mirror

Reflector &
License Plate

Dirt and damage

Counter Operation
Exhaust

Joint looseness and damage

Muffler

Exhaust muffler performance

Body & Frame Looseness and damage

3. INSPECTION/ADJUSTMENT

3-4

ZX /SCOUT 50

Abnormal
Conditions
Happened Last
Time

Check if the abnormal
conditions occur again

Lubrication points

Others

Remove carbon deposits on
combustion chamber,
breather hole and exhaust
muffler

BRAKE DRUM/SHOE
«Brake Shoe Wear»
Replace the brake shoes if the arrow on the

brake arm aligns with reference mark“” on the
brake panel when the brake is fully applied.

«Brake Drum Wear/Damage»
Check the brake drum appearance for damage.

Check if the brake lining wear is within the
specified service limit. Check the brake
operation for abnormal noise and brake drum
inside for wear or damage.

BRAKE DISK/LINING

«Brake Disk Surface and Brake Pad
Wear»

Check the brake disk surface for scratch.
Check if the brake pad wear is within the
specified service limit.

«Brake Disk Runout Inspection»
Jack the motorcycle wheels off the ground and

check if the brake disk runout is within the
specified service limit.

BRAKE FLUID LEVEL INSPECTION

«Brake Master Cylinder Fluid Level
Inspection »

Turn the steering handlebar upright and check
if the front brake fluid level is within the

specified limits through the front brake master
cylinder check hole.

“” Marks <Rear>

Adjusting Nuts

<Front>

3. LUBRICATION SYSTEM

3-5

MOVING DEVICE

TIRES

«Tire Pressure»
Check the tire pressure.

Tire Pressure (one rider)

Front: 1.50 kg/cm²
Rear: 1.75 kg/cm²

Tire Size:

Front: 120/70-12
Rear: 120/70-12

«Axle Nut/Axle Shaft Looseness»
Check the front and rear axle nuts for

looseness.
If the axle nuts are loose, tighten them to the
specified torques.

Torques:

Front: 5.0 7.0kg-m
Rear: 11.0 13.0kg-m

«Wheel Rim/Spoke Plate Damage»
Check the wheel rim and spoke plate for wear or

damage and measure the rim runout.

Tire pressure should be checked when

tires are cold.

*

Brake Disk

Brake Lining Service

Limit Mark

Brake Master Cylinder

3. INSPECTION/ADJUSTMENT

3-6

DAMPING DEVICE

SHOCK ABSORBERS

«Oil Leak/Damage»
Fully apply the front brake and check the

action of the front shock absorber by
compressing it several times.
Check the entire shock absorber assembly for
looseness or damage.
Check the action of the rear shock absorber
by compressing it several times.
Check the entire shock absorber assembly for
looseness or damage.

POWER DRIVE SYSTEM

TRANSMISSION CASE

Check the rear wheel transmission case
surrounding area for oil leaks.
Stop the engine and remove the oil check bolt.

The gear oil level shall be at the oil check bolt
hole. If the oil level is low, add the specified
oil to the proper level.

Specified Gear Oil: SAE10W90#
Install and tighten the oil check bolt.
Torque: 1.0 1.5kg-m
Start the engine and check for oil leaks.

Axle Nut

Place the motorcycle on its main stand on

level ground.

*

Axle Nut

Rear Wheel

3. LUBRICATION SYSTEM

3-7

ELECTRICAL EQUIPMENT

IGNITION APPARATUS

«Spark Plug»
Remove the frame center cover.

Remove the spark plug cap and spark plug.
Check the spark plug for wear, fouling and
carbon deposits.
Remove the fouling and carbon deposits with a
spark plug cleaner or wire brush.

Specified Spark Plug
BR8HSA

Spark Plug Gap: 0.6 0.7mm

«Ignition Apparatus»

Remove the right side rail. (ð12-4)
Remove the A.C. generator fan cover.
(ð7-3)
Remove the four bolts attaching the fan and
then remove the fan.
Warm up the engine and check the ignition

timing with a timing light.

When the engine is running at the specified rpm, the
ignition timing is correct if the “F” mark on the
flywheel aligns with the index mark on the
crankcase within ±2°.

Ignition Timing:

15.5°±2°BTDC/2000rpm

Gap, Wear and

Fouling Deposits

Washer Damage

Cracks

Bolt

The CDI ignition timing is not adjust

-

able.

If the timing is incorrect, check the CDI
unit, ignition coil and A.C. generator and
replace any faulty parts.

*

0.6-0.7mm

3. INSPECTION/ADJUSTMENT

3-8

ENGINE

BODY

«At High and Low Speeds»

Adjust the idle speed to the specified range by
turning the throttle stop screw and air screw.

Idle Speed:
2100±100rpm

«Air Cleaner»
Remove the air cleaner cover by removing the

six air cleaner cover screws.
Remove the air cleaner element.

The engine must be warm for accurate idle

speed adjustment.

*

Screws

Air Screw

Throttle Stop Screw

Index Mark

F Mark

3. LUBRICATION SYSTEM

3-9

Wash the air cleaner element in detergent oil,
squeeze out and allow to dry.

After washing, soak the element in clean engine
oil SAE 15W-40# and squeeze out excess oil.
Reinstall the element.

«Cylinder Compression»

Remove the spark plug and insert a
compression gauge.
Open the throttle valve fully and push the
starter button for 7 8 seconds to test the
compression.

Compression :

11.5kg/cm ²
If the compression is low, check for the

following:

• Leaking cylinder head gasket

• Worn piston/cylinder

If the compression is high, it indicates that
carbon deposits have accumulated on the

combustion chamber and the piston head.

LUBRICATION SYSTEM
«Oil Filter Cleaning»
Disconnect the oil tube at the oil pump side and

allow oil to drain into a clean container.
Remove the tube clip at the oil tank side and
disconnect the oil tube.
Remove the oil filter.

Soak in oil

Air Cleaner

Squeeze out

and dry

Wash

Squeeze out

excess oil

Warm up the engine before compression

test.

*

Never use gasoline or organic vaporable

oil with acid or alkali for washing.

*

3. INSPECTION/ADJUSTMENT

3-10

Clean the oil filter screen with compressed air.
Install the oil filter in the reverse order of
removal and fill the oil tank with specified oil
up to the proper level.
Bleed air from the oil pump and oil lines.

«Oil Pump Condition»

Open the throttle valve fully and check that the
index mark on the pump body aligns with the
aligning mark on the oil pump control lever.
Reference tip alignment within 1mm of index
mark on open side is acceptable.
Start and idle the engine, then slowly open the
throttle to increase engine rpm and check the
operation of the oil pump control lever.
If adjustment is necessary, adjust the oil pump
control cable by loosening the control cable
lock nut and turning the adjusting nut.
After adjustment, tighten the lock nut.

If the oil pump is not synchronized properly, the
following will occur:

• Excessive white smoke or hard starting due to

pump control lever excessively open

• Seized piston due to pump control lever

insufficiently open

Filter Screen

Oil Filter

• Connect the oil tubes securely.

• Install the tube clip at the oil tank side

and also install the clip to the lower oil
tube that goes to the oil pump.

• Check for oil leaks.

*

Adjust oil pump control cable after the

throttle grip free play is adjusted.

*

Reference tip alignment within 1mm of

index mark on open side is acceptable.
However, the aligning mark on the control
lever must never be on the closed side of
the index mark, otherwise engine damage
will occur because of insufficient

*

Adjusting Nut

Lock Nut

Control Lever Aligning Mark

Clip

3. LUBRICATION SYSTEM

3-11

FUEL SYSTEM

«Throttle Grip Free Play»
Measure the throttle grip free play.
Free Play: 2 6mm

If the throttle grip free play does not fall within
the specified range, adjust by loosening the
lock nut and turning the adjusting nut.

OTHERS

LIGHTS

«Headlight»

Adjust the headlight beam by loosening the
headlight adjusting bolt and moving the adjusting
bolt forward and backward to a proper position.
Tighten the adjusting bolt.

Adjusting Nut

Lock Nut

3. INSPECTION/ADJUSTMENT

3-12

Headlight Adjusting Bolt

4. LUBRICATION SYSTEM

4-0

ZX /SCOUT 50

4

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

LUBRICATION SYSTEM

__________________________________________________________________________________

SERVICE INFORMATION ............................................................4-2

TROUBLESHOOTING ..................................................................4-2

OIL PUMP REMOVAL..................................................................4-3

OIL PUMP INSPECTION..............................................................4-3

OIL PUMP INSTALLATION.........................................................4-4

OIL PUMP BLEEDING ..................................................................4-5

OIL TANK .....................................................................................4-6

4

4. LUBRICATION SYSTEM

4-1

ZX /SCOUT 50

LUBRICATION SYSTEM

4. LUBRICATION SYSTEM

4-2

ZX /SCOUT 50

SERVICE INFORMATION

GENERAL INSTRUCTIONS

• Use care when removing and installing the oil pump not to allow dust and dirt to enter the engine and oil

line.

• Do not attempt to disassemble the oil pump.

• Bleed air from the oil pump if there is air between the oil pump and oil line.

• If the oil is disconnected, refill the oil line with motor oil before connecting it.

SPECIFICATIONS

• Recommended Motor Oil: SAE20W20# 2-stroke Motor Oil

• Oil Capacity : 0.80 liter

Light comes on : 0.25 liter

TROUBLESHOOTING

Excessive white smoke or carbon deposits on spark plug

• Oil pump not properly synchronized (excessive oil)

• Poor quality oil

Engine overheating

• Oil pump not properly adjusted (insufficient oiling)

• Poor quality oil

Seized piston

• No oil in tank or clogged oil line

• Oil pump not properly adjusted (insufficient oiling)

• Air in oil line

• Faulty oil pump

Oil not flowing out of tank to engine

• Clogged oil tank cap breather hole

• Clogged oil filter

4. LUBRICATION SYSTEM

4-3

ZX /SCOUT 50

OIL PUMP REMOVAL

Remove the met-in box. (ð12-4)

Disconnect the oil pump control cable from the
pump body.
Disconnect the oil inlet line from the oil pump.
Then, disconnect the oil outlet line.

Remove the oil pump control cable plate bolt
and copper washer.
Remove the oil pump from the crankcase.

OIL PUMP INSPECTION

Remove the oil pump and inspect the following
items:

• Weakened O-ring

• Damage to crankcase mating surface

• Damage to pump body

• Control lever operation

• Oil leaks through oil seals

• Worn or damaged pump pinion

OIL PUMP INSTALLATION

Do not allow foreign matters to enter the

crankcase. Before removing the oil pump,
clean the oil pump and crankcase surfaces.

*

Do not disassemble the oil pump which

cannot be used after disassembly.

*

Before disconnecting the oil line, clip the

oil line to avoid oil flowing out and then
plug the oil line after it is disconnected.

*

Oil Outlet Line

Oil Inlet Line

Control Cable

Oil Pump

O-ring

Pinion

Control Lever

Control Cable plate

4. LUBRICATION SYSTEM

4-4

ZX /SCOUT 50

Install the oil pump onto the crankcase.

Install the oil pump control cable plate.
Connect the oil inlet line and oil outlet line
properly.
Connect the oil pump control cable.
Bleed air from the oil pump.

OIL PUMP BLEEDING

• Lubricate the O-ring with grease or

engine oil before installation.

• Make sure that the oil pump is inserted

into the crankcase.

• Apply molybdenum disulfide or grease to

the pump pinion.

*

Grease or Engine Oil

Control Cable

Oil Outlet Line

4. LUBRICATION SYSTEM

4-5

ZX /SCOUT 50

OIL INLET LINE/OIL PUMP BLEEDING
Fill the oil tank with recommended oil.

Place a shop towel around the oil pump.
Disconnect the oil inlet line from the oil pump
and clip it.
Fill the oil pump with oil by squirting clean oil
through the joint. (About 3cc)
Fill the oil line with oil and connect it to the oil
pump.

OIL OUTLET LINE BLEEDING

1. Disconnect the oil outlet line and bend it into
U shape. Force air out of the tube by filling
it with oil.

2. Start the engine and allow it to idle with the
oil control lever in the fully open position.
Visually check the oil flow.

3. If there is no oil flowing out within 1 minute,
bleed air from the oil inlet line and oil pump.

OIL TANK

OIL TANK REMOVAL

• Air in the oil lines will block oil flow and

result in severe engine damage.

• Bleed air from the oil lines and oil pump

whenever the oil lines or pump have been
removed or there is air in the oil lines.

*

Bleed air from the oil inlet line first, then

bleed air from the oil outlet line.

*

• Never run the engine in a closed area.

• Do not increase the engine speed at will.

*

Oil Pump

Oil Tube

Oil Outlet Line

Oil O

utlet Line

4. LUBRICATION SYSTEM

4-6

ZX /SCOUT 50

Remove the rear carrier. (ð12-5)
Remove the frame body cover. (ð12-5)
Remove the oil meter connector.
Remove the two bolts attaching the oil tank.
Disconnect the oil inlet line.
Drain the oil inside the oil tank into a clean
container.
Remove the oil tank.
The installation sequence is the reverse of
removal.

• Connect the oil line properly.

• Bleed air from the oil pump after

installation.

• The oil tube clip (at the oil tank side)

must be locked from inside of the oil tube
joint.

*

Wire Connector

5. ENGINE REMOVAL/INSTALLATION

5-0

ZX / SCOUT

5

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

ENGINE REMOVAL/INSTALLATION

__________________________________________________________________________________

SERVICE INFORMATION ............................................................5-1

ENGINE REMOVAL......................................................................5-2

ENGINE INSTALLATION.............................................................5-4

5

5. ENGINE REMOVAL/INSTALLATION

5-1

ZX / SCOUT

SERVICE INFORMATION

GENERAL INSTRUCTIONS

• Parts requiring engine removal for servicing:

Crankcase
Crankshaft

TORQUE VALUES

Engine mounting bolt 4.5 5.5kg-m
Rear shock absorber lower mount bolt 2.4 3.0kg-m
Engine hanger bracket bolt 3.5 4.5kg-m

4.5

5.5kg

-m4.5

5.5kg

-m3.5

4.5kg

-

m

5. ENGINE REMOVAL/INSTALLATION

5-2

ZX / SCOUT

ENGINE REMOVAL

Remove the frame body cover. (ð12-5)
Remove the two bolts attaching the air cleaner
case.
Loosen the band between the air cleaner and
carburetor to remove the air cleaner case.
Remove the carburetor cap.

Disconnect the oil pump control cable from the
pump body.
Disconnect the oil inlet line from the oil pump.

Disconnect the auto bystarter, A.C. generator
and starter motor wire connectors.

Remove the spark plug cap.

After the oil inlet line is disconnected, plug

the oil line opening to prevent oil from
flowing out.

*

Carburetor Cap

Oil Inlet Line

Oil Pump Control Cable

Band

Air Cleaner Case

AC Generator Wire

Connector

Spark Plug

Cap

Bolt

5. ENGINE REMOVAL/INSTALLATION

5-3

ZX / SCOUT

Remove the rear brake adjusting nut and
disconnect the brake cable from the
crankcase.
Remove the rear brake cable clamp and rear
brake cable.
Remove the cooling air tube band on the left
crankcase cover and disconnect the cooling air
tube.
Remove the rear shock absorber lower mount
bolt.

Remove the right and left engine mounting nuts.
Take out the right and left engine mounting
bolts.
Lift the frame upward to separate it from the
engine and be careful not to damage the rear
fender.

ENGINE HANGER BRACKET REMOVAL
Remove the engine hanger bracket bolt and

engine hanger bracket.
The installation sequence is the reserve of
removal.

Torque: 3.5 4.5kg-m

ENGINE HANGER BRACKET
INSPECTION

Engine Mounting Nuts

Rear Brake Cable

Clamp

Rear Shock Absorber Lower Mount Bolt

Engine Hanger Bracket Bolt

5. ENGINE REMOVAL/INSTALLATION

5-4

ZX / SCOUT

Inspect the stopper rubbers and bushings for
damage and replace with new ones if
necessary.

ENGINE INSTALLATION

Install the engine in the reverse order of
removal.

Torque Values:
Engine mounting bolt : 4.5 5.5kg-m
Rear shock absorber lower mount bolt:

2.4 3.0kg-m

Perform the following inspections and
adjustments after installation.

• Throttle cable

• Oil pump control cable (ð3-10)

• Rear brake cable (ð3-4)

• Oil pump bleeding (ð4-5)

Cables and wires should be routed

properly.

*

Bushings

Engine Hanger

Stopper Rubbers

6. CYLINDER HEAD/CYLINDER/PISTON

6-0

ZX / SCOUT

6

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

CYLINDER HEAD/CYLINDER/PISTON

__________________________________________________________________________________

SERVICE INFORMATION ............................................................6-2

TROUBLESHOOTING ..................................................................6-2

CYLINDER HEAD.........................................................................6-3

CYLINDER/PISTON......................................................................6-6

6

6. CYLINDER HEAD/CYLINDER/PISTON

6-1

ZX / SCOUT

Torque: 1.5

1.7kg

-mTorque: 1.1

1.7kg

-

m (cold)

6. CYLINDER HEAD/CYLINDER/PISTON

6-2

ZX / SCOUT

SERVICE INFORMATION

GENERAL INSTRUCTIONS

• The cylinder head, cylinder and piston can be serviced with the engine installed in the frame.

• Before disassembly, clean the engine to prevent dust from entering the engine.

• Remove all gasket material from the mating surfaces.

• Do not use a driver to pry between the cylinder and cylinder head, cylinder and crankcase.

• Do not damage the cylinder inside and the piston surface.

• After disassembly, clean the removed parts before inspection. When assembling, apply the speci fied

engine oil to movable parts.

SPECIFICATIONS

Standard (mm) Service Limit (mm)

Item SC10AS SC10AS

Cylinder head warpage  0.10
Piston O.D.(5mm from bottom of piston skirt) 38.955 38.970 38.90
Cylinder-to- piston clearance 0.10
Piston pin hole I.D. 12.002 12.008 12.03
Piston pin O.D. 11.994 12.0 11.98
Piston -to-piston pin clearance ← ←
Piston ring end gap (top/second) 0.10 0.25 0.40
Connecting rod small end I.D. 17.005 17.017 17.03
Cylinder bore 39.039.025 39.05

TORQUE VALUES

Cylinder head bolt 1.5 1.7kg-m
Exhaust muffler joint lock nut 1.0 1.4kg-m
Exhaust muffler lock bolt 3.0 3.6kg-m
Spark plug 1.1 1.7kg-m

TROUBLESHOOTING

Compression too low, hard starting
or poor performance at low speed Abnormal noisy piston

• Leaking cylinder head gasket • Worn cylinder and piston

• Loose spark plug • Worn piston pin or piston pin hole

• Worn, stuck or broken piston and piston rings • Worn connecting rod small end bearing

• Worn or damaged cylinder and piston

Compression too high, overheating
or knocking Abnormal noisy piston rings

• Excessive carbon build-up in cylinder head • Worn, stuck or broken piston rings

or on piston head • Worn or damaged cylinder

6. CYLINDER HEAD/CYLINDER/PISTON

6-3

ZX / SCOUT

CYLINDER HE AD

REMOVAL

Remove the rear carrier.
Remove the frame body cover. (ð12-5)

Remove the spark plug cap.
Remove the three bolts attaching the fan cover
to remove the fan cover.
Remove the two joint lock nuts on the front of
the exhaust muffler and then remove the two
exhaust muffler lock bolts.
Remove the bolt attaching the engine hood to
remove the engine hood.
The installation sequence is the reverse of
removal.

Remove the spark plug.
Remove the cylinder head bolts and the
cyl inder head.

Remove the cylinder head gasket.

COMBUSTION CHAMBER

Loosen the bolts diagonally in 2 or 3 times.

*

Cylinder head Bolts

Bolts

When installing the exhaust muffler, first

tighten the two nuts on the front and then
tighten the two bolts.

*

Cylinder Head

Spark Plug

Fan Cover/Engine Hood

Spark Plug Cap

6. CYLINDER HEAD/CYLINDER/PISTON

6-4

ZX / SCOUT

DECABONIZING

Remove the carbon deposits from the
com bustion chamber

CYLINDER HEAD INSPECTION
Check the cylinder head for warpage with a

straight edge and feeler gauge.
Service Limit:

0.10mm replace if over

CYLINDER HEAD INSTALLATION
Install the cylinder head on the cylinder

properly.

Install a new cylinder head gasket onto the
cylinder.

Avoid damaging the combustion cha

m-ber

wall and cylinder mating surface.

*

Be ca

reful not to damage the mating

su rfaces.

*

Cylinder head Gasket

Combustion Chamber

Mating Surface

6. CYLINDER HEAD/CYLINDER/PISTON

6-5

ZX / SCOUT

Cylinder Head Bolts Installation
Install and tighten the cylinder head bolts

diagonally in 2 or 3 times.
Torque: 1.5 1.7kg-m
Install the spark plug.

Torque: 1.1 1.7kg-m

Engine Hood Installation

Install the engine hood.
Install the spark plug cap.

Perform the following inspections after
installation:

• Compression test

• Abnormal engine noise

• Cylinder air leaks

Cylinder head Bolts

Bolts

Bolt

Cylinder Head

Spark Plug

Spark Plug

Engine Hood

6. CYLINDER HEAD/CYLINDER/PISTON

6-6

ZX / SCOUT

CYLINDER/PISTON

CYLINDER REMOVAL

Remove the met-in box and seat.
Remove the frame body cover.
Remove the cylinder head.
Remove the two exhaust muffler joint lock nuts
and two exhaust muffler lock bolts.
Remove the exhaust muffler.
Remove the cylinder.
Remove the cylinder gasket.

PISTON REMOVAL
Remove the piston pin clip to remove the

piston pin and piston.

Spread each piston ring and remove by lifting it
up at a point just opposite the gap.
Remove the expander.

• Do not damage or scratch the piston.

• Do not apply side force to the

connect-ing rod when removing the
piston pin.

• Place clean shop towels in the

crank-case to keep the piston pin clip

*

Do not pry between the cylinder and

crankcase or strike the fins.

*

Piston Pin Clip

Joint Loc

k Nuts

Piston

Piston Pin

Cylinder

6. CYLINDER HEAD/CYLINDER/PISTON

6-7

ZX / SCOUT

CYLINDER/PISTON INSPECTION
Check the cylinder and piston for wear or

damage.
Clean carbon deposits from the exhaust port
area.

Measure the cylinder bore at three levels of A,
B and C in both X and Y directions. Avoid
the port area. Take the maximum figure
measured to determine the cylinder bore.

Service Limit:

39.05mm replace if over

Inspect the top of the cylinder for warpage.
Service Limit:

0.10mm replace if over

The cylinder has an A mark or no mark on

it. When replacing the cylinder with a new
one, use a cylinder having the same mark
as the old one.

*

Be careful not to damage the cylinder

inside wall.

*

6. CYLINDER HEAD/CYLINDER/PISTON

6-8

ZX / SCOUT

Measure the piston O.D. at a point 5mm from
the bottom of the piston skirt.

Service Limit:

38.90mm replace if below

Measure the piston-to-cylinder clearance.
Service Limit:

0.10mm replace if over

Measure the piston pin hole I.D.
Service Limit:

12.03mm replace if over

Measure the piston pin O.D.
Service Limit:

11.98mm replace if below

Measure the piston-to-piston pin clearance.
Service Limit:

0.03mm replace if over

PISTON RING INSPECTION

A Mark Nuts

6. CYLINDER HEAD/CYLINDER/PISTON

6-9

ZX / SCOUT

Measure each piston ring end gap.
Service Limits: Top/Second

0.40mm replace if over

CONNECTING ROD SMALL END
INSPECTION

Install the piston pin and bearing in the
connecting rod small end and check for
excessive play.
Measure the connecting road small end I.D.

Service Limit:

17.03mm replace if over

PISTON/CYLINDER INSTALLATION
First install the expander in the second ring

groove.
Then install the top and second rings in their
respective ring grooves.
The piston rings should be pressed into the
grooves with even force.
After installation, check and make sure that
each ring is flush with the piston at several
points around the ring.
A ring that will not compress means that the
ring groove has carbon deposits in it and
should be cleaned.

Install a new cylinder gasket on the mating surface
between the cylinder and crankcase.

Set each piston ring squarely into the

cylinder using the piston and measure the
end gap.

*

<Small End I.D. Measurement>

piston

Top ring

Sencond ring

expander

6. CYLINDER HEAD/CYLINDER/PISTON

6-10

ZX / SCOUT

Make sure that the ring end gaps are aligned
with the piston ring pins in the ring grooves.

Lubricate the cylinder inside and piston rings
with engine oil and install the piston into the
cylinder while compressing the piston rings.

Install the cylinder head.
Torque: 1.5 1.7kg-m
Install the exhaust muffler and tighten the

exhaust muffler joint lock nuts.
Torque: 1.0 1.4kg-m
Tighten the exhaust muffler lock bolts.
Torque: 3.0 3.6kg-m
Install the frame covers.

Be careful not to damage the piston.

*

Cylinder Gasket

Ring Pins

7. A.C. GENERATOR

7-0

ZX / SCOUT

7

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

A.C. GENERATOR

__________________________________________________________________________________

SERVICE INFORMATION ............................................................7-2

A.C. GENERATOR REMOVAL.....................................................7-3

A.C. GENERATOR INSTALLATION............................................7-4

7

7. A.C. GENERATOR

7-1

ZX / SCOUT

Torque: 3.5

4.0kg

-mTorque: 0.8

1.2kg

-mTorque: 0.6

1.0kg

-mTorque: 0.8

1.2kg

-

m

7. A.C. GENERATOR

7-2

ZX / SCOUT

SERVICE INFORMATION

GENERAL INSTRUCTIONS

• All A.C. generator maintenance and inspection can be made with the engine installed.

• Refer to Section 15 for A.C. generator inspection.

TORQUE VALUE

Flywheel nut : 3.5 4.0kg-m

SPECIAL TOOLS
Flywheel puller

Universal holder

A.C. GENERATOR REMOVAL

Remove the three bolts attaching the fan cover to

7. A.C. GENERATOR

7-3

ZX / SCOUT

remove the fan cover.

Remove the cooling fan by removing the four
bolts.

Hold the flywheel with an universal holder and
then remove the flywheel nut.

Remove the A.C. generator flywheel using the
flywheel puller.

Fan Cover

Bolts

Bolt

Nut

Universal Holder

Cooling Fan

7. A.C. GENERATOR

7-4

ZX / SCOUT

Remove the A.C. generator wire connector.

Remove the two pulser coil bolts and pulser
coil from the right crankcase.
Remove the pulser coil wire clamp from the
right crankcase.
Remove the two bolts attaching the A.C.
generator stator.

A.C. GENERATOR
INSTA LLATION

Install the A.C. generator stator and pulser coil
wire clamp onto the right crankcase, and then
install the pulser coil.

Connect the A.C. generator wire connector.

Be careful not to damage the

di scon-nected wire.

*

Lock Nut Wrench

A.C. Generator Wire Connector

Stator

Flywheel Puller

Pulser Coil

Wire Clamp

7. A.C. GENERATOR

7-5

ZX / SCOUT

Clean the taper hole in the flywheel off any
burrs and dirt.
Install the woodruff key in the crankshaft
keyway.

Install the flywheel onto the crankshaft with the
flywheel groove aligned with the crankshaft
woodruff key.
Hold the flywheel with the universal holder and
install the flywheel flange nut.

Torque: 3.5 4.0kg-m
Start the engine and check the ignition timing.

(ð3-7)
Install other removed parts in the reserve order
of removal.

A.C. Generator Wire Connector

Woodruff Key

Universal Holder

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-0

ZX / SCOUT

8

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

__________________________________________________________________________________

SERVICE INFORMATION ............................................................8- 2

TROUBLESHOOTING ..................................................................8- 2

KICK STARTER............................................................................8- 3

DRIVE BELT .................................................................................8- 7

DRIVE PULLEY.............................................................................8- 9

STARTER PINION........................................................................8-11

CLUTCH/DRIVEN PULLEY..........................................................8-12

8

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-1

ZX / SCOUT

MODEL SC10AS

Torque:

3.5 4.5kg-m

Torque:

5.0

6.0kg

-

m

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-2

ZX / SCOUT

SERVICE INFORMATION

GENERAL INSTRUCTIONS

• Avoid getting grease and oil on the drive belt and pulley faces.

SPECIFICATIONS

SC10AS

Item Standard (mm) Service Limit (mm)

Drive pulley collar O.D. 20.01 20.025 24.24
Movable drive face I.D. 20.035 20.085 19.97
Weight roller O.D. 13.0 12.4
Clutch outer I.D. 107 107.2 107.5
Driven face spring free length 87.9 82.6
Driven face O.D. 33.965 33.985 33.94
Movable driven face I.D. 34.034.25 34.06
Drive belt width 18 17

TORQUE VALUES

Drive face nut 3.5 4.0kg-m
Clutch outer nut 3.5 4.5kg-m
Clutch drive plate nut 5.0 6.0kg-m

SPECIAL TOOLS
Lock nut wrench, 39mm Universal holder

Clutch spring compressor Lock nut socket wrench, 32mm
Bearing outer driver 37x40mm Bearing driver pilot, 17mm
One-way clutch puller Outer driver, 24x26mm

TROUBLESHOOTING

Poor performance at high speed or
Engine starts but motorcycle won‘t move lack of power

• Worn drive belt • Worn drive belt

• Broken ramp plate • Weak driven face spring

• Worn or damaged clutch lining • Worn weight roller

• Faulty driven face

Engine stalls or motorcycle creeps

• Broken clutch weight spring

KICK STARTER

LEFT CRANKCASE COVER REMOVAL

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-3

ZX / SCOUT

Remove the drive belt cooling air tube
connector circlip.
Remove the nine left crankcase cover bolts,
left crankcase cover and dowel pins.
Inspect the left crankcase cover seal rubber for
damage or deterioration.

KICK STARTER SPINDLE REMOVAL
Remove the kick lever from the kick starter

spindle.
Remove the circlip and washer from the kick
starter spindle.

Slightly rotate the kick starter spindle to
remove the kick starter driven gear together
with the friction spring.

Remove the kick starter spindle and return spring
from the left crankcase cover.
Remove the kick starter spindle bushing.

Kick Starter Spindle

Left Crankcase Cover

Bolt

Friction Spring

Kick Starter Driven Gear

Washer

Circlip

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-4

ZX / SCOUT

KICK STARTER SPINDLE INSPECTION
Inspect the kick starter spindle and gear for

wear or damage.
Inspect the return spring for weakness or
damage.
Inspect the kick starter spindle bushing for
wear or damage.

Check the kick starter driven gear for wear or
damage.
Check the friction spring for wear or damage.

Inspect the kick starter spindle and driven gear
forcing parts for wear or damage.

Kick Starter Spindle

Spindle

Friction Spring

Kick Starter Driven Gear

washer

Spindle Bushing

Return Spring

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-5

ZX / SCOUT

KICK STARTER INSTALLATION
Install the kick starter spindle bushing and

return spring onto the left crankcase cover.

Properly install the kick starter driven gear and
friction spring as the figure shown.

First install the washer and then the circlip onto the
kick starter spindle.
Install the kick lever.

If the hooks of the return spring can not be

installed properly, use a screw driver to
press them into their locations respectively.

*

Kick Starter Spindle Forcing Part

Friction Spring

Kick Starter Driven Gear

Return Spring

Kick Starter Spindle

Ki

ck Starter Driven Gear Forcing Part

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-6

ZX / SCOUT

LEFT CRANKCASE COVER
INSTALLATION

First install the dowel pins and then the seal
rubber.

Install the left crankcase cover and tighten the
nine bolts diagonally.
Connect the drive belt cooling air tube and
install the circlip.

DRIVE BELT

Remove the left crankcase cover.
INSPECTION

Check the drive belt for cracks, separation or
abnormal or excessive wear.

Left Crankcase Cover

Dowel Pins

Washer

Circlip

For drum brake, note the location of the

brake cable clamp and install the rear
brake cable in place with the clamp.

*

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-7

ZX / SCOUT

Measure the drive belt width.
Service Limit:

16.5mm replace if below

REPLACEMENT

Remove the nine left crankcase cover bolts
and left crankcase cover. (ð8-3)
Hold the clutch outer with the universal holder
and remove the 14mm clutch outer nut and
clutch outer.

Hold the drive pulley with the holder and
remove the drive face nut.
Remove the starting ratchet.
Remove the drive pulley face.

Remove the drive belt from the clutch/ driven
pulley.

Use specified genuine parts for

replace-ment.

*

Clutch Outer

Drive Face Nut

Drive Face

Clutch Outer Nut

Ratchet

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-8

ZX / SCOUT

DRIVE BELT INSTALLATION
Turn the driven pulley clockwise and lift it up

to expand the drive belt groove and then install
a new drive belt.

Set the drive belt on the drive pulley.
Install the drive pulley face, starting ratchet and
washer, then tighten the drive face nut.

Torque: 3.5 4.0kg-m

DRIVE PULLEY

REMOVAL

Hold the drive pulley with the holder and remove
the drive face nut.
Remove the starting ratchet, washer and drive
pulley face.

Clutch/Driven Pulley

Drive Belt

Drive Belt

Drive Pulley Face

Washer

Drive Belt

Starting Ratchet

Drive Face Nut

When installing the drive face nut, make

sure that the tooth spaces of the drive
pulley face and starting ratchet align with
the teeth of the crankshaft.

*

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-9

ZX / SCOUT

MOVABLE DRIVE FACE
DISASSEMBLY

Remove the movable drive face and drive
pulley collar from the crankshaft.

Remove the ramp plate.

Remove the weight rollers.

Movable Driv

e Face

Ramp Plate

Drive Face Nut

Starting Ratchet

Drive Pulley Face

Drive Pulley Collar

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-10

ZX / SCOUT

MOVABLE DRIVE FACE INSPECTION

Check each weight roller for wear or damage.
Measure each roller O.D.

Service Limit:

12.4mm replace if below

DRIVE PULLEY INSTALLATION

Install the drive pulley collar and movable drive
face onto the crankshaft.

Install the drive belt on the crankshaft.
Install the drive face, starting ratchet and washer,
then tighten the 12mm drive face nut.

Torque: 3.5 4.0kg-m

Keep grease or oil off the drive belt and

drive pulley faces.

*

Weight Roller

Movable Drive Face

Drive Pulley Collar

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-11

ZX / SCOUT

STARTER PINION

REMOVAL

Remove the left crankcase cover. (ð8-3)
Remove the drive pulley. (ð8-9)
Remove the starter pinion.

INSPECTION
Inspect the starter pinion seat for wear.

Inspect the starter pinion for smooth operation.
Inspect the starter pinion shaft forcing parts for
wear and damage.

INSTALLATION
Apply a small amount of grease to the starter

pinion teeth.
Install the starter pinion in the reverse order of
removal.

CLUTCH/DRIVEN PULLEY

CLUTCH/DRIVEN PULLEY REMOVAL

Remove the drive pulley. (ð8-9)
Hold the clutch outer with the universal holder and
remove the 14mm clutch outer nut.
Remove the clutch outer.

Drive Face Nut

Starting Ratchet

Drive Pulley Face

Starter Pinion

Shaft Forcing Par

ts

Starter Pinion

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-12

ZX / SCOUT

Remove the clutch/driven pulley.
Remove the drive belt from the clutch/driven
pulley.

CLUTCH/DRIVEN PULLEY
DIS-ASSEMBLY

Compress the clutch/driven pulley spring with
the clutch spring compressor and remove the
39mm drive plate nut.
Remove the driven face spring.

Remove the seal collar.

Clutch/Driven Pulley

Universal Holder

Clutch Outer

14mm Clutch Outer Nut

Clutch Spring Compressor

Lock Nut Wrench, 39mm

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-13

ZX / SCOUT

Pull out the guide roller pins from the driven
pulley and then remove the O-rings and oil seal
from the driven pulley.

CLUTCH/DRIVEN PULLEY
INSPECTION

Inspect the clutch outer for wear or damage.
Measure the clutch outer I.D.

Service Limit:

107.5mm replace if below

Check the clutch shoes for wear or damage.
Measure the clutch lining thickness.

Service Limit: 2.0mm replace if below

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-14

ZX / SCOUT

Measure the driven face spring free length.
Service Limit:

82.6mm replace if below

Check the driven face assembly for wear or
damage.
Measure the driven face O.D.

Service Limit: 33.94mm replace if below
Check the movable driven face for wear or

damage.
Measure the movable driven face I.D.

Service Limit: 34.06mm replace if below
Check the guide roller pins for stepped wear.

DRIVEN PULLEY FACE BEARING
REPLACEMENT

Check the needle bearings in the driven face and
replace them if they have excessive play, damage
or abnormal noise.
Drive the inner bearing out of the driven pulley
face.

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-15

ZX / SCOUT

Remove the snap ring and drive the outer
bearing out of the driven face.

Drive a new outer bearing into the driven face
with the sealed end facing up.
Seat the snap ring in its groove.

Drive in a new needle bearing into the driven face
with the mark facing up.

Snap Ring

Bearing Outer Driver, 37x40mm

Outer Bearing

Pack all bearing cavities with 5.0

5.6g

grease.
Specified grease: 230 Heat-resistant

grease

*

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-16

ZX / SCOUT

CLUTCH/DRIVEN PULLEY ASSEMBLY
First install the movable driven face onto the

driven face. Then, install the guide roller pins,
O-rings and a new oil seal.

Install the seal collar.

Set the driven pulley, driven face spring and clutch
assembly onto the clutch spring compressor.
Compress the tool and install the 39mm drive plate
nut.
Tighten the 39mm nut to the specified torque.

Torque: 5.0 6.0kg-m

Oil Seal

O-rings

Guide Roller Pin

Driven Pulley

Bearing Driver Pilot

Outer Driver, 24x26mm

8. KICK STARTER/DRIVE PULLEY/

CLUTCH/DRIVEN PULLEY

8-17

ZX / SCOUT

CLUTCH/DRIVEN PULLEY
INSTALLATION

Install the drive belt on the clutch/driven pulley
and then install the clutch/driven pulley onto the
drive shaft.

Install the clutch outer.
Hold the clutch outer with the universal holder.
Install and tighten the 10mm clutch outer nut.

Torque: 3.5 4.5kg-m
Install the left crankcase cover. (ð8-6)

Universal Holder

Clutch Outer

Clutch/Driven Pulley

9. FINAL REDUCTION

9-0

ZX / SCOUT

9

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

FINAL REDUCTION

__________________________________________________________________________________

SERVICE INFORMATION ............................................................9-2

TROUBLESHOOTING ..................................................................9-2

FINAL REDUCTION DISASSEMBLY ...........................................9-3

FINAL REDUCTION INSPECTION..............................................9-3

FINAL REDUCTION ASSEMBLY .................................................9-6

9

9. FINAL REDUCTION

9-1

ZX / SCOUT

9. FINAL REDUCTION

9-2

ZX / SCOUT

SERVICE INFORMATION

Speci fied Oil: SAE90#
At disassembly: 0.12 liter
At change: 0.1 liter

SPECIAL TOOLS
Bearing remover set, 12mm

Bearing remover set, 15mm
Crankcase assembly collar
Crankcase assembly shaft
Bearing outer driver, 37x40mm
Bearing outer driver, 32x35mm
Bearing driver pilot, 17mm
Bearing driver pilot, 15mm
Bearing driver pilot, 12mm
Bearing outer driver handle A

TROUBLESHOOTING

Engine starts but motorcycle won‘t move

• Damaged transmission

• Seized or burnt transmission

Abnormal noise

• Worn, seized or chipped gears

• Worn bearing

Oil leaks

• Oil level too high

• Worn or damaged oil seal

FINAL REDUCTION

9. FINAL REDUCTION

9-3

ZX / SCOUT

DISAS-SEMBLY

Remove the rear wheel. (ð14-3)
Remove the left crankcase cover. (ð8-3)
Remove the clutch/driven pulley. (ð8-7)
Drain the transmission gear oil into a clean
container.
Remove the transmission case cover attaching
bolts.
Remove the transmission case cover.
Remove the gasket and dowel pins.

Remove the final gear and countershaft.

FINAL REDUCTION INSPECTION

Inspect the countershaft and gear for wear or
damage.

Inspect the final gear and final shaft for wear,

Final Gear

Countershaft

Dowel Pin

Countershaft

Driver shaft

Driver shift

Bolts

9. FINAL REDUCTION

9-4

ZX / SCOUT

damage or seizure.

Check the left crankcase bearings for
excessive play and inspect the oil seal for wear
or damage.

Inspect the drive shaft and gear for wear or
damage.
Check the transmission case cover bearings for
excessive play and inspect the final shaft
bearing oil seal for wear or damage.

BEARING REPLACEMENT (Transmission

Do not remove the transmission case cover

except for necessary part replace-ment.
When replacing the drive shaft, also replace
the bearing and oil seal.

*

Final Shaft

Oil Seal

Drive Shaft Bearing

9. FINAL REDUCTION

9-5

ZX / SCOUT

Case Cover)
Remove the transmission case cover bearings

using the bearing remover.
Remove the final shaft oil seal.

Drive new bearings into the transmission case
cover.

BEARING REPLACEMENT (Left
Crankcase Cover)

Remove the drive shaft.
Remove the drive shaft oil seal.
Remove the left crankcase bearings using the
bearing remover.

Drive new bearings into the left crankcase.

Drive Shaft Bearing

Bearing Outer Driver, 32x35mm

Bearing Remover Set

Bearing Remover Set, 12mm

Bearing Outer Driver Handle A

9. FINAL REDUCTION

9-6

ZX / SCOUT

Install a new drive shaft oil seal.

FINAL REDUCTION
ASSEMBLY

Install the drive shaft into the left crankcase.

Install the final gear and final shaft into the left
crankcase.

Install the countershaft and gear into the left

Drive Shaft

Bearing Outer Driver

9. FINAL REDUCTION

9-7

ZX / SCOUT

crankcase.
Install the resin washer onto the counter-shaft.
Install the dowel pins and a new gasket.

Install the transmission case cover.

Install and tighten the transmission case cover
bolts.
Install the clutch/driven pulley. (ð8-17)
Install other removed parts in the reverse order
of removal.

After installation, fill the transmission case with the
specified oil.

Resin Washer

Countershaft

Transmission Case Cover

Bolts

Dowel Pins

9. FINAL REDUCTION

9-8

ZX / SCOUT

Specified Gear Oil: SAE90#
Oil Capacity: at disassembly: 0.12 liter

at change: 0.1 liter

Install and tighten the oil check bolt.
Torque: 1.0 1.5kg-m
Start the engine and check for oil leaks.

Check the oil level from the oil check bolt hole
and add the specified oil to the proper level if
the oil level is low.

• Place the motorcycle on its main stand

on level ground.

• Check the sealing washer for wear or

damage.

*

Drain Bolt

Oil Check Bolt Hole/Filler

10. CRANKCASE/CRANKSHAFT

10

-

0

ZX / SCOUT

10

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CRANKCASE/CRANKSHAFT

__________________________________________________________________________________

SERVICE INFORMATION ............................................................10-2

TROUBLESHOOTING ..................................................................10-2

CRANKCASE SEPARATION........................................................10-3

CRANKSHAFT REMOVAL...........................................................10-3

CRANKSHAFT INSPECTION.......................................................10-4

CRANKSHAFT INSTALLATION..................................................10-5

CRANKCASE ASSEMBLY............................................................10-7

10