KYMCO Venox 250 User manual

KYMCO
SERVICE MANUAL
VENOX 250
KYMCO
Overseas Sales Division
Overseas Service Department

PREFACE
This Service Manual describes the technical features and servicing
procedures for the KYMCO VENOX 250.
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 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 DIVISION
OVERSEAS SERVICE DEPARTMENT
MAR 2002
The information, specifications, an
d
illustrations included in this manual
may be different from the motorcycle
in case specifications are changed.
＊

TABLE OF CONTENTS
GENERAL INFORMATION......................................................................... 1
INSPECTION/ADJUSTMENT...................................................................... 2
LUBRICATION SYSTEM............................................................................. 3
FUEL SYSTEM............................................................................................... 4
ENGINE REMOVAL/INSTALLATION...................................................... 5
CYLINDER HEAD/VALVES........................................................................ 6
CRANKSHAFT/PISTON/CYLINDER......................................................... 7
GENERATOR/LEFT CRANK CASE COVER........................................... 8
CLUTCH/GEAR SHIFT MECHANISM...................................................... 9
TRANSMISSION SYSTEM...........................................................................10
COOLING SYSTEM ......................................................................................11
FRONT WHEEL/SUSPENSION/STEERING.............................................12
REAR WHEEL/BRAKE/SUSPENSION......................................................13
HYDRAULIC BRAKE ...................................................................................14
IGNITION SYSTEM ......................................................................................15
CHARGING SYSTEM ...................................................................................16
STARTING SYSTEM.....................................................................................17
LIGHTS/INSTRUMENT/SWITCHES/HORN............................................18

1. GENERAL INFORMATION
1-0
VENOX 250
1
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
GENERAL INFORMATION
__________________________________________________________________________________
ENGINE SERIAL NUMBER/IDENTIFICATION............................. 1- 1
SPECIFICATIONS .............................................................................. 1- 2
SERVICE PRECAUTIONS................................................................. 1- 3
SERVICE INFORMATION ................................................................ 1-10
TORQUE VALUES............................................................................. 1-12
SPECIAL TOOLS................................................................................ 1-14
LUBRICATION POINTS.................................................................... 1-16
WIRING DIAGRAM........................................................................... 1-17
CABLE & HARNESS ROUTING....................................................... 1-18
TROUBLESHOOTING....................................................................... 1-22
1

1. GENERAL INFORMATION
1-1
VENOX 250
ENGINE SERIAL NUMBER/IDENTIFICATION
Location of Engine Serial Numbe
r
Vehicle Identification Serial Numbe
r
Location of Fra
m
e Serial Numbe
r

1. GENERAL INFORMATION
1-2
VENOX 250
SPECIFICATIONS
Motorcycle name & Model No. VENOX 250
Chassis name & Model No. RA50AA
Overall length (mm) 2325
Overall width (mm) 840
Overall height (mm) 1080
Wheel base (mm) 1600
Engine type 4∞
Displacement (cc) 249.4
Fuel type Nonleaded gasoline
Front 80
Rear 95
Dry weight (kg) Total 175
Front 90
Rear 100
Gross weight (kg) Total 190
Front 120/80-17
Tires Rear 150/80-15
Ground clearance (mm) 150
Braking distance (m) <6.9(40km/h)
Perform-
ance Min. turning radius (m) 2.750
Starting system Self motor
Type DOHC8V
Cylinder arrangement Twin cylinder
Combustion chamber type Dome head
Valve arrangement DOHC
Bore x stroke (mm) 58.0 x 47.2
Compression ratio 11±0.2
Compression pressure
(kg/cm²−rpm) 17±2
Max. output (ps/rpm) 27.5/10500
Max. torque (kg-m/rpm) 2/8500
Open 4°
Intake
(1mm) Close 35°
Engine
Open 31°
Port
timin
g
Exhaust
(1mm) Close 0°
Intake 0.1mm
Valve clearanc
e
(Cold engine) Exhaust 0.1mm
Idle speed (rpm) 1300±100
Lubrication type Forced
p
ressure &
wet sump
Oil pump type Inner/outer rotor
Oil filter type Wire gauze filter
Lubrication System
Oil capacity 2.5 liter
Cooling Type Air＋water cooling
Air cleaner type Paper element
Fuel capacity 14 liter
Type CVK
Main Jet NO Front:112 Rear:108
Venturi dia.(mm) φ30 equivalent
Fuel System
Carburetor
Throttle type Butterfly type
Type Fully Transistor
Ignition timing B.T.D.C10°/1000rpm
Breaker type ⎯
CR8E
Spark plug
Ignition System
Spark plug gap 0.6～0.7mm
Electrical Equipment
Battery Capacity 12V8AH
Clutch Type Wet multi-disc clutch
Type 5-speed transmission
Operating method Foot operated
Type International type
1st gear 2.733
2nd gear 1.8
3rd gear 1.375
4th gear 1.111
Power Drive System
Transmission Gear
Reduction
ratio
5th gear 0.965
Front Caster angle 35°
Axle Front 2.0Tire pressure
(k
g
/c
m
²)(2 riders) Rear 2.25
Left 40°
Turning angle Right 40°
Front Disk brake
Moving Device
Brake system
type Rear Drum brake
Front Telescopic fork
Suspension Rear Telescopic fork
Front Oil damper spring
Damping Device
Shock absorbe
r
Rear Oil damper spring

1. GENERAL INFORMATION
1-3
VENOX 250
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
1-4
VENOX 250
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
1-5
VENOX 250
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
1-6
VENOX 250
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.
Check the double connector cover for
proper coverage and installation.
Before connecting a terminal, check for
damaged terminal cover or loose
negative terminal.
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
1-7
VENOX 250
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
1-8
VENOX 250
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 no
t
p
ull too
ti
g
ht!
Do not press
or squeeze
the wire.

1. GENERAL INFORMATION
1-9
VENOX 250
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 not bend or twist control cables.
Damaged control cables will not operate
smoothly and may stick or bind.
Do you understand
the instrument? Is
the instrument set
correctly?
Remove rust !

1. GENERAL INFORMATION
1-10
VENOX 250
Symbols:
The following symbols represent the
servicing methods and cautions included in
this service manual.
: Apply engine oil to the
specified points. (Use the
designated engine oil for
lubrication.)
: Apply grease for lubrication.
: Use special tool.
: Caution
: Warning
Grease
S
p
ecial
＊
Engine Oil

1. GENERAL INFORMATION
1-11
VENOX 250
SERVICE INFORMATION
ENGINE Standard (mm) Service Limit (mm)
Item Venox 250 Venox 250
Cylinder head warpage ⎯⎯
Piston O.D.(10mmfrom bottom of piston skirt) 57.975～57.99 57.81
Cylinder-to- piston clearance 0.01～0.35 0.35
Piston pin hole I.D. 16.000～16.006 16.06
Piston pin O.D. 15.994～15.997 15.90
Piston-to-piston pin clearance 0.003～0.012 0.10
Piston ring end gap (top/second) No1:0.10～0.25 No2: 0.2～0.35 0.5
Connecting rod small end I.D. 16.013～16.028 16.09
Cylinder bore 58.0～58.015 58.20
Connecting rod big end side clearance 0.09～0.29 ⎯
Connecting rod big end radial clearance ⎯⎯
Crankshaft runout A/B 0.03 ⎯
CARBURETOR Venox 250
Venturi dia. 30 mm
Type CVK
Float level FR:17.5 mm RR:19.0mm
Main jet FR:#110 RR:#108
Slow jet #35
Pilot screw opening 2±½
Idle speed 1300±100 rpm
Throttle grip free play 2～6mm

1. GENERAL INFORMATION
1-12
VENOX 250
FRAME Standard (mm) Service Limit (mm)
Item Venox 250 Venox250
Axle shaft runout 0.3/100mm 0.5
Radial 0.5 2.0
Front wheel rim runout Axial 0.5 2.0
Front shock absorber spring free length ⎯⎯
Rear wheel rim runout 0.5 2.0
Brake drum I.D. Rear 160 161
Brake lining thickness Front/Rear 5.0/5.0 2.0/2.0
Rear shock absorber spring free length ⎯⎯
ELECTRICAL EQUIPMENT Venox 250
Capacity 12V8AH
Voltage 13.0～13.2V
Battery
Charging current 0.9A/5～10H
Spark plug (NGK) CR8E
Spark plug gap (mm) 0.6～0.7
Primary 3.57～4.83Ω
Ignition coil
resistance Secondary (with plug cap) 14.96～20.24KΩ
Pulser coil resistance (20℃) 396～594Ω
Ignition timing 10°BTDC/1000rpm

1. GENERAL INFORMATION
1-13
VENOX 250
TORQUE VALUES
ENGINE
Item Thread dia. (mm) Torque (kg-m) Remarks
Plate oil flowby
Connect rod nut
Oil drain
Plate ball brg holder
Drum gear shift
Shift fork comp
Sw assy neutral
Crank case
Case cooler tank pipe
Oil seperator
Sprocket oil pump nut
Oil sump
Motor assy starter
Holder head (FR/RR)
Tension guide pivot
Lifter assy tensioner (FR/RR)
Lifter assy tensioner screw pan
(FR/RR)
Guide upper tensioner
Head cover
Clutch nut lock
Clutch
One way clutch socket bolt
One way clutch bolt UBS (left)
R cover
Cover change
Water pump
A.C.G.
L cover
Sprocket drive bolt special
Spark plug
Head bolt stud
M5×12
M7×0.75
M12×15
6×12
6×20
6×12
8×60, 8×65,8×75, 8×82
6×35,6×85,6×60,6×40,6×30,6×90
6×20
6×20
8
6×25
6×25
8×151
8×131, 8×48,8×65
6×22
6×6
6×12
6×30
20
6×22
8×12
10×35
6×30
6×30
6×55,6×10
10×35
6×30,6×35
10×30
CR8E
6×40
0.8～1.2
2.0～2.4
2.0～3.0
0.8～1.2
0.8～1.2
0.8～1.2
1.0～1.4
1.9～2.3
1.0～1.4
0.8～1.2
0.8～1.2
1.8～2.3
0.8～1.2
0.8～1.2
3.0～3.4
1.9～2.3
1.8～2.2
1.0～1.4
0.35～0.5
0.8～1.2
0.8～1.2
5.5～6.5
0.8～1.2
1.8～2.5
7.5～8.5
0.8～1.2
0.8～1.2
0.8～1.2
7.5～8.5
0.8～1.2
5.5～6.5
1.0～1.4
0.7～1.1

1. GENERAL INFORMATION
1-14
VENOX 250
FRAME
Item Thread dia. Torque (kg-m) Remarks
Strg stem nut
Thread comp strg head
Top bridge
Bottom bridge
Front axle bolt
Rear axle nut
Front brake caliper
Oil bolt
Master cylinder holder
Rear suspension cush bolt(upper)
Rear suspension cush bolt(under)
Front suspension cush bolt(axle)
Rear fork pivot nut
Up ENG hanger
Front ENG hanger
Rear ENG hanger
Handle nut
EXH Muffler bolt
Front step bolt
Rear winker
22×1.0
26×1.0
8×1.25
10×1.25
14×1.5
16×1.5
8×1.25
10×1.25
6×1.0
6×1.0
10×1.25
8×1.25
14×1.5
10×1.25
10×1.25
8×1.25
10×1.25
12×1.25
8×1.25
10×1.25
10×1.25
6.0～8.0
0.15～2.5 or 1.2
1.7～2.1
2.4～3.0
6.0～8.0
8.0～10.0
2.4～3.0
3.0～4.0
0.8～1.2
0.8～1.2
3.0～4.0
3.0～4.0
6.0～8.0
3.5～4.5
3.5～4.5
2.4～3.0
3.5～4.5
5.0～6.0
3.0～3.6
3.0～4.0
1.6～1.8
Back 90°
Torque specifications listed above are for important fasteners. Others should be tightened to
standard torque values below.
STANDARDTORQUEVALUES 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
4,5mm screw
6mm screw, SH bolt
6mm flange bolt, nut
8mm flange bolt, nut
10mm flange bolt, nut
0.2～0.4,0.35～0.5
0.7～1.1
1.0～1.4
2.4～3.0
3.5～4.5

1. GENERAL INFORMATION
1-15
VENOX 250
SPECIAL TOOLS
Tool Name Tool No. Remarks
Lock nut socket wrench E046 9-6
Lock nut wrench F006 12-11,12-12
Flywheel holder E021 8-3,8-4
Flywheel puller E042 8-4
Valve wrench E036 2-13
Vacuum & CO adjuster E043 2-14
Vacuum gauge E045 2-14
Valve spring compressor E040 6-8,6-9
Piston installer E041 7-8
Clutch lifter holder E047 9-6
Bearing remover E030 10-10
Bearing driver handle E014 12-8,13-6
Steering stem wrench F007 12-11,12-12

1. GENERAL INFORMATION
1-16
VENOX 250
LUBRICATION POINTS
ENGINE
NO. Lubrication Points Lubricant Remarks
1 Crankcase sliding & movable parts SAE 5W-50 SF
2 Cylinder movable parts SAE 5W-50 SF
3 Drive chain SAE 80~90
4 Kick lever movable parts Grease
5 Front suspension SAE 10W 400cc/piece
6 Rear suspension SAE 5W 99cc/piece
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.
Front Brake Leve
r
Rear Wheel
Bearing
Throttle Cable
Bar Side Stand Pivot
Grease
Engine Oil
Speedometer Gear
/
Front Shock
Absorber Lower
Mount
Bushings/Pivot
Grease Grease
Grease
Grease Engine Oil
Drive Chain
Brake Cam
/
Anchor Pin