Sym Wolf SB 250 Ni User manual

Wolf SB 250 Ni
SERVICE MANUAL
20120309
FOREWORD
HOW TO USE THIS MANUAL
CONTENTS
MECHANISM ILLUSTRATION

Foreword
This service manual contains the technical data of each component inspection and
repair for the SANYANG PD25A series motorcycle. The manual is shown with
illustrations and focused on Service Procedures”, Operation Key Points”, and
Inspection Adjustment” so that provides technician with service guidelines.
Copyright reserved.
If the style and construction of the motorcycle, PD25A series motorcycle, are
different from that of the photos, pictures shown in this manual, you should follow
the actual vehicle layout. Specifications may be changed without notice.
Service Department
SANYANG INDUSTRY CO., LTD.
Homepage
Contents

How to use this manual
This service manual describes basic information of individual parts and system
inspection & service for SANYANG PD25A series motorcycle. In addition, please
refer to the manual contents for detailed information for the model year.
The first chapter covers general information and trouble diagnosis.
The second chapter covers service maintenance information and special tools
manual.
The third to the 9th chapters cover engine and driving systems.
The 10th chapter covers cooling systems.
The 11th to the 13th chapters contain the parts of vehicle frame.
The 14th chapter is electrical appliances.
The 15th chapter is emission control system.
The 16th chapter is electrical diagram.
Please see index of content for brief information and quick guide.

Content
Page Content Index
1-1 ~ 1-19 General Information
1
2-1 ~ 2-16 Maintenance Information
2
3-1 ~ 3-45 Injection System 3
4-1 ~ 4-14 Lubrication / Clutch / Transmission 4
5-1 ~ 5-8 AC Generator / Starting Clutch 5
6-1 ~ 6-8 Engine Removal 6
7-1 ~ 7-16 Cylinder Head / Valve 7
8-1 ~ 8-10 Cylinder / Piston 8
9-1 ~ 9-14 Crankshaft / Crankcase / Shifting Gear 9
10-1 ~ 10-14 Cooling System 10
11-1 ~ 11-10 Brake System 11
12-1 ~ 12-14 Steering / Front Wheel / Front Fork 12
13-1 ~ 13-12 Rear Wheel / Rear Cushion 13
14-1 ~ 14-26 Electrical System 14
15-1 ~ 15-10 Emission Control System 15
16-1 ~ 16-2 Wiring Diagram 16

Mechanism Illustration
Start /
Engine stop
switch
Main
Switch
RR brake
pedal
Starter relay
Air cleaner
Fuel tank cap
Winker relay
Battery
Headlight
dimmer /
Winker / Horn
switch
Ignition
il
ECU
Headlight
Fuse
Regulator/
Rectifier
Shifting
pedal
Meter
FR. Brake lever
Clutch lever Taillight
FR winker
RR. winker
Muffler

1. General Information
Symbols and Marks ··················1-1
General Safety···························1-2
Service Precautions··················1-3
Specifications -··························1-9
Torque Values(Engine)·············1-10
Torque Values(Frame) ··············1-11
Torque Values ···························1-11
Troubleshooting························1-12
Lubrication Points·····················1-17
Symbols and Marks
Symbols and marks are used in this manual to indicate what and where the special service are
needed, in case supplemental information in procedures is needed for these symbols and marks,
explanations will be added to the text instead of using the symbols or marks.
Warning Means that serious injury or even death may result if procedures are
not followed.
Caution Means that equipment damages may result if procedures are not
followed.
Engine oil
Limits to use SAE 10W-30 API SG class oil. Warranty will not cover
the damage that caused by not apply with the limited engine oil.
(Recommended oil: Bramax G-3 oil)
Grease King Mate G-3 is recommended.
Gear oil King Mate gear oil serials are recommended. (Bramax HYPOID GEAR
OIL # 140)
Locking
sealant
Apply sealant; medium strength sealant should be used unless
otherwise specified.
Oil seal Apply with lubricant.
Renew Replace with a new part before installation.
Brake fluid Use recommended brake fluid DOT3 or WELLRUN brake fluid.
Special tools Special tools
Correct Meaning correct installation.
Wrong Meaning wrong installation.
Indication Indication of components.
Directions Indicates position and operation directions
Components assembly directions each other.
Indicates where the bolt installation direction, --- means that bolt goes
through the component (invisibility).
1-1

1. General Information
General Safety
Carbon monoxide Battery
If you must run your engine, ensure the place is
well ventilated. Never run your engine in a closed
area. Run your engine in an open area, if you
have to run your engine in a closed area, be sure
to use a ventilator.
Caution
1-2
Caution
Exhaust contains toxic gas, which may cause
one to lose consciousness and even result in
death.
Gasoline
Gasoline is a low ignition point and explosive
material. Work in a well-ventilated place, no flame
or spark allowed in the work place or where
gasoline is being stored.
Caution
Gasoline is highly flammable, and may
explode under some conditions, keep it away
from children.
Used engine oil
Caution
Prolonged contact with used engine oil (or
transmission oil) may cause skin cancer although
it might not be verified.
We recommend you to wash your hands with
soap and water right after contacting. Keep
the used oil beyond reach of children.
Hot components
Caution
Components of the engine and exhaust
system can become extremely hot after
engine running. They remain very hot even
after the engine has been stopped for some
time. When performing service work on these
parts, wear insulated gloves and wait until the
vehicle is cooling down.
‧ Battery emits explosive gases; flame is strictly
prohibited. Keeps the place well ventilated
when charging the battery.
‧ Battery contains sulfuric acid (electrolyte),
which can cause serious burns, so be careful
not to get the sulfuric acid on your eyes or
skin. If you get battery acid on your skin, flush
it off immediately with water. If you get battery
acid in your eyes, flush it off immediately with
plenty of water and then go to hospital to
consult an ophthalmologist.
‧ If you swallow it by mistake, drink a lot of
water or milk, and take some laxative such as
vegetable oil and then go to see a doctor.
‧ Keep electrolyte beyond reach of children.
Brake shoe
Do not use compressed air or a dry brush to clean
components of the brake system; use a vacuum
cleaner or the equivalent to avoid dust flying.
Caution
Inhaling brake shoe or pad ash may cause
disorders and cancer of the breathing system
Brake fluid
Caution
Spilling brake fluid on painted, plastic, or rubber
parts may cause damage to the parts. Place a
clean towel on the above-mentioned parts for
protection when servicing the brake system.
Keep the brake fluid beyond reach of children.

1. General Information
Service Precautions
Always use with SANYANG genuine parts and
recommended oils. Using non-genuine parts for
SANYANG vehicle may damage it.
1-3
Special tools are designed for removal and
installation of components without damaging the
part. Using wrong tools may result in damage.
When servicing this bike, use only metric tools,
metric bolts, and nuts. Using wrong tools and
fasteners may damage this vehicle.
Clean the outside of the parts or the cover
before removing it from the bike. Otherwise, dirt
and deposit accumulated on the part's surface
may fall into the engine, chassis, or brake
system, and cause damage.
Wash and clean parts with high ignition point
solvent, and blow them dry with compressed air.
Pay special attention to O-rings or oil seals
because most cleaning agents have an adverse
effect on them.
Never bend or twist a control cable to prevent
unsmooth control and premature worn out.
Rubber parts may become deteriorated when
old and easy to be damaged by solvent and oil.
Check these parts before installation to make
sure that they are in good condition, replace if
necessary.
When loosening a component, which has
different sized fasteners, operate with a
diagonal pattern and work from inside out.
Loosen the small fasteners first. If the bigger
ones are loosen first, small fasteners may
receive too much stress.
Store complex components such as
transmission parts in the proper assemble order
and tie them together with a wire for ease of
installation later.
Note the reassemble position of the important
components before disassembling them to
ensure they will be reassembled in correct
dimensions (depth, distance or position).
Components not to be reused should be
replaced when disassembled including gaskets
metal seal rings, O-rings, oil seals, snap rings,
and split pins.

1. General Information
The length of bolts and screws for assemblies,
cover plates or boxes is different from one
another; make sure they are correctly installed.
In case of confusion, Insert the bolt into the hole
to compare its length with other bolts, if its
length outside the hole is the same with other
bolts, it is a correct bolt. Bolts for the same
assembly should have the same length.
1-4
Tighten assemblies with different dimension
fasteners as follows: Tighten all the fasteners
with fingers, then tighten the big ones with
special tool first diagonally from inside toward
outside, important components should be
tightened 2 to 3 times with appropriate
increments to avoid warp unless otherwise
indicated. Bolts and fasteners should be kept
clean and dry. Do not apply oil to the threads.
When installing oil seal, fill the groove with
grease, install the oil seal with the name of the
manufacturer facing outside, and check the
shaft on which the oil seal is to be installed for
smoothness and for burrs that may damage the
oil seal.
Remove residues of the old gasket or sealant
before reinstallation, grind with a grindstone if
the contact surface has any damage.
The ends of rubber hoses (for fuel, vacuum, or
coolant) should be pushed as far as they can
go to their connections so that there is enough
room below the enlarged ends for tightening
the clamps.
Groove
Clamp
Rubber and plastic boots should be properly
reinstalled to the original correct positions as
designed
Connector
Boots
The tool should be pressed against two (inner
and outer) bearing races when removing a ball
bearing. Damage may result if the tool is
pressed against only one race (either inner race
or outer race). In this case, the bearing should
be replaced. To avoid damaging the bearing,
use equal force on both races.
Manufacturer's name
Both of these examples can result in bearing damage.

1. General Information
Lubricate the rotation face with specified
lubricant on the lubrication points before
assembling.
1-5
●Check if positions and operation of installed
parts are correct and proper.
●Make sure service safety each other when
conducting by two persons.
●Note that do not let parts fall down.
Before battery removal operation, you have to
remove the battery negative (-) cable first.
Avoid using tools like open-end wrench, which
may contact with body or create spark.
After service completed, make sure all
connection points is secured.
Battery positive (+) cable should be connected
firstly.
And the two posts of battery have to be
greased after connected the cables.
●Make sure that the battery post caps are
located properly after the battery posts had
been serviced.
●If a fuse is burned, it has to find out the cause
and solved it. And then replace with specified
capacity fuse.
Capacity
verification

1. General Information
●When separating a connector, its locker has to
be unlocked first. Then, conduct the service
operation.
1-6
●Do not pull the wires as removing a connector
or wires. Hold the connector body.
●Make sure if the connector pins are bent,
extruded or loosened.
●Insert the connector completely.
●If there are two lockers on two connector sides,
make sure the lockers are locked in properly.
●Check if any wire loose.
●Check if the connector is covered by the twin
connector boot completely and secured
properly.
●Before connecting terminals, check if the boot
is cracked or the terminal is loose.
●Insert the terminal completely.
●Check if the boot covers the terminal.
●Do not let boot open facing up.
●Secure wires and wire harnesses to the frame
with respective wire bands at the designated
locations. Tighten the bands so that only the
insulated surfaces contact the wires or wire
harnesses
●Wire band and wire harness have to be
clamped secured properly.
●Do not squeeze wires against the weld or its
clamp.

1. General Information
●Do not let the wire harness contact with
rotating, moving or vibrating components
when routing the harness.
1-7
●Keep wire harnesses far away from the hot
parts.
●Avoid wire harnesses from sharp edges or
corners, and also avoid the jutted-out ends of
bolts and screws.
●Route harnesses so that they neither pull too
tight nor have excessive slack.
●Protect wires or wire harnesses with electrical
tape or tube if they contact a sharp edge or
corner. Thoroughly clean the surface where
tape is to be applied.
●Secure the rubber boot firmly as applying it on
wire harness.
Never Touch
●Never use wires or harnesses which insulation
has broken. Wrap electrical tape around the
damaged parts or replace them.
●Never clamp or squeeze the wire harness
when installing other components.
Never clamp or squeeze
the wire harness
Never too tight

1. General Information
●Do not let the wire harness be twisted when
installation.
1-8
●Wire harnesses routed along the handlebar
should not be pulled too tight or have
excessive slack, use rubber covering against
adjacent or surrounding parts in all steering
perimeters.
●Before operating a test instrument, the
operator should read the operation manual of
the instrument, and then conducts test in
accordance with the instruction.
●Use sand paper to clean connector
pins/terminals if rust is found. And then
continue the connection operation.
Do you know how to set the
instrument to its measurement
position and the insert locations
of its two probes?
Clean rust

1. General Information
1-9
Specifications
Maker SYM Model PD25A1
Overall Length 2005 mm Front TELESCOPIC FORK
Overall Width 790 mm Suspension
System Rear UNIT SWING
Overall Height 1050 mm Front 110/70-17 54H
Dimension
Wheel Base 1320 mm Tire
Specifications Rear 140/70-17 66H
Front 82 kg
Rear 91 kg Front DISK (ø 288 mm)
Curb
Weight Total 173 kg Brake System
Rear DISK (ø 222 mm)
Passengers/Weight Two / 150 kg Max. Speed > 140 km/hr
Front 112 kg Performance Climb Ability < 28°
Rear 211 kg Primary
Reduction 2.826 (65/23T)
Weight
Total
Weight
Total 323 kg Final
Reduction 2.69 (35/13T)
Type/ Cooling
System
Water-cooled
4-stroke
gasoline engine
Clutch Wet multi-plate
Installation and
arrangement
Vertical, below
center, incline
15°
Reduction
Transmission 6 speed, circulated
Fuel Used Above 92
unleaded Speedometer 0 ~ 199 km/hr
Fuel supply injection Horn 1
Bore Ø 71.0 mm Muffler Expansion & Pulse
Type
Stroke 63.0 mm Exhaust Pipe Position and
Direction Right side and
Backward
C
yl
in
d
e
rNumber/Arrangem
ent Single Cylinder Lubrication System Forced / Wet sump
Displacement 249.4 cc Solid Particulate -
Compression Ratio 10.5 : 1 CO < 3.0 %
Max. HP 25 ps / 7500
rpm
Exh
aust
Con
cent
rati
on HC < 1600 PPM
Max. Torque 2.35 kg-m /
6000 rpm E.E.C. √
Ignition Full transistor
Ignition P.C.V. √
Engine
Starting System Electrical
starter Catalytic reaction control
system √

1. General Information
1-10
Torque Values (Engine)
Item Q’t Thread Dia. (mm) Torque Value(kgf-m) Remarks
Cylinder stud bolt 4 10 1.0~1.4
Cylinder head nut 4 10 3.6~4.0
Cylinder head right bolt 2 6 1.0~1.4
Cylinder head side cover bolt 3 6 1.0~1.4
Cylinder head cover bolt 4 6 0.8~1.2
Cylinder head stud bolt (inlet
i)
2 6 1.0~1.4
Cylinder head stud bolt (EX.
i)
2 8 2.4~3.0
Air inject pipe bolt 4 6 1.0~1.4
Tappet adjustment screw nut 4 5 0.7~1.1 Lubricate with oil
Spark plug 1 10 1.0~1.2
Camshaft gear fix bolt 2 6 1.0~1.4
Camshaft setting plate bolt 1 6 0.8~1.2
Cam chain tensioning bolt 2 6 1.0~1.4
Throttle fix nut 2 6 0.8~1.2
Engine oil draining bolt 1 12 3.5~4.5
Engine oil strainer cap 1 30 1.3~1.7
Flywheel nut 1 14 8.5~10.5
R. crankcase cover bolt 12 6 0.8~1.2
L. crankcase cover bolt 11 6 0.8~1.2
L. crankcase rear cover bolt 2 6 0.8~1.2
Oil pump screw 2 6 0.7~1.1
Oil pump cover bolt 2 6 0.8~1.2
Water pump impeller 1 7 1.0~1.4
Water pump cover bolt 4 6 0.8~1.2
Crankcase bolt 11 6 0.8~1.2
Oil strainer cover bolt 2 6 0.8~1.2
Balancing shaft drive gear bolt 4 6 0.8~1.2
Primary drive gear nut 1 16 8.5~10.5
Balancing shaft fix nut 1 14 8.5~10.5
Clutch lifter plate bolt 6 6 1.0~1.4
Clutch fix nut 1 16 8.5~10.5
ACG fix bolt 3 6 0.8~1.4
Drive gear bolt 2 6 0.8~1.2
The torque values listed are important tightening torque values. Please see standard values for
those not listed in the table.

1. General Information
1-11
Torque Values (Frame)
Item Q’t
yThread Dia. (mm) Torque Value (Kg-m) Remarks
Mounting bolt for steering handle post 4 8 1.0~1.4
Lock nut for steering stem 1 22 6.0~8.0
Steering top cone race 1 22 0.15~0.25
Front wheel axle nut 1 12 6.0~8.0
Rear wheel axle nut 1 14 10.0~12.0
Rear drive sprocket nut 4 8 2.7~3.0
Front cushion mounting bolt 4 8 3.0~3.5
Rear cushion upper connection bolt 1 10 3.5~4.5
Rear cushion lower connection bolt 1 10 3.5~4.5
Brake lever bolt 2 6 0.8~1.2
Brake hose bolt 4 10 3.0~4.0
Brake air-bleeding valve 2 6 0.8~1.0
Front brake disc mounting bolt 3 6 3.7~4.3
Rear brake disc mounting bolt 2 8 2.4~3.0
Gear change bolt 1 6 0.8~1.2
Brake clipper mounting bolt 2 6 1.5~2.0
Engine suspension nut 2 8 2.4~3.0
upper part of engine &
frame
Engine assembly nut 2 8 3.0~4.0
engine front part & engine
hanger
Engine assembly nut 1 10 4.5~5.5
engine rear part & frame
Special Bolt 8 8 1.5~2.5
Swing arm pivot nut 1 10 10.0~12.0
Muffler mounting nut 2 8 1.0~1.2
Muffler mounting bolt 2 8 3.2~3.8
The torque values listed in above table are for more important tightening torque values. Please refer to
standard values for those not listed in the table.
Torque Values
Type Tighten Torque Type Tighten Torque
5mm bolt, nut 0.45~0.60kgf-m 4mm screw 0.10~0.15kgf-m
6mm bolt, nut 0.80~1.20kgf-m 5mm screw 0.35~0.50kgf-m
8mm bolt, nut 1.80~2.50kgf-m 6mm screw, SH nut 0.70~1.10kgf-m
10mm bolt, nut 3.00~4.00kgf-m 6mm flange bolt, nut 1.00~1.40kgf-m
12mm bolt, nut 5.00~6.00kgf-m 8mm flange bolt, nut 2.40~3.00kgf-m
3mmscrew 0.05~0.08kgf-m 10mm flange bolt, nut 3.50~4.50kgf-m

1. General Information
Troubleshooting
A. Engine cannot be started or difficult to be started
Check and adjustment Fault condition Probable causes
1-12
Press the fuel injector feed
pipe and confirm whether
there is fuel in the feed
p
i
p
e
The fuel supply to the fuel
injector is sufficient
The fuel injector is not
supplied with sufficient fuel
Check the spark plug ignition
condition
Perform cylinder compression
pressure test
Sparks
1. Check the fuel amount in the fuel tank
2. Check if the fuel pipe and the vacuum
tube are blocked or not
3. Malfunction of fuel pump relay or wiring
4. Evaporative Emission Control System
clogged
5. Malfunction of fuel pump
6. The fuel strainer is blocked or not
Week sparks or no spark
Normal cylinder
compression pressure
Low or no compression
pressure
1. Piston ring seized
2. Malfunction of cylinder valves
3. Worn cylinder and piston ring
4. Cylinder gasket leakage
5. Sand hole in the compression parts
1. Malfunction of spark plug
2. Spark plug contamination
3. Malfunction of ECU
4. Malfunction of the AC Generator
5. Ignition coil is in open or short circuit
6. Ignition coil shorted or open circuit
7. Malfunction of main switch
Restart the en
g
ine
No ignition With signs of ignition but
the engine cannot be
started
1. Malfunction of throttle valve operation
2. Air sucked into intake manifold
3. Incorrect ignition timing
Remove and check the spark
plug
Dry spark plug
1. Contaminated or clogged fuel injector
2. Malfunction of throttle valve operation
3. Malfunction of fuel pressure regulator
Wet spark plug

1. General Information
B. Engine runs sluggish (Speed does not go up, lack of power)
Check and adjustment Fault condition
Accelerate gradually and check
engine RPM
Engine RPM can be increased Engine RPM cannot be increased
Check ignition timing
(Using ignition lamp)
Check cylinder compression
pressure (using pressure gauge)
Correct ignition timing Incorrect ignition timing
Normal compression pressure Abnormal compression pressure
Check if the fuel injector is
clogged or not
Not clogged Clogged
Remove and check the spark
plug
Check if the engine is over
heated
No contamination or discoloration
Contaminated or discolored
No knocking Knocking
1. Clogged air cleaner
2. Poor fuel supply
(Test on level road)
1. Replace the fuel injector
1. Remove the dirt
2. Incorrect spark plug heat range
3. Incorrect spark plug gap
1. Worn out piston or cylinder
2. Abnormal fuel injector
3. Poor fuel quality
4. Carbon deposit in the combustion chamber
5. Abnormal ignition timing
6. clutch slippage
1. Carbon deposit in the combustion chamber
2. Malfunction of fuel injector
3. Poor fuel quality
4. Abnormal ignition timing
Continually drive in acceleration
or high speed
Normal Engine overheated
1. Malfunction of ECU
2. Malfunction of AC Generator
1. Worn out cylinder or piston ring
2. Cylinder gasket leakage
3. and hole in compression parts
4. Valve deterioration
5. Jammed piston ring
3. Fuel tank emission control system clogged
4. Clogged exhaust pipe
5. Clogged fuel injector
Engine RPM cannot be
increased
3. clutch shoe damaged
1. clutch slippage
2. poor clutch contact surface
Probable causes
1-13

1. General Information
C. Engine runs sluggish (especially in low speed and idling)
Check and adjustment
Check ignition timing
(using ignition lamp)
Incorrect ignition timing (malfunction of
ECU or AC Generator)
1. Abnormal throttle body insulator gasket
Normal Abnormal
Check for any air sucked in
through the throttle body insulator
2. Abnormal throttle body installation
3. Abnormal inlet pipe gasket
4. Malfunction of ECU
No air sucked in Air sucked in
Probable causesFault condition
1. Contaminated spark plug
2. Malfunction of ECU
3. Malfunction of AC Generator
4. Malfunction of ignition coil
5. Open or short circuit in spark plug leads
6. Malfunction of main switch
Good spark Poor spark
Remove the spark plug and
check the spark condition
D. Engine runs sluggish (High speed)
Normal
Check the fuel pump supply
Check if fuel injector clogged
1. insufficient fuel
2. fuel hose clogged, pressed
3. EEC clogged
Good Poo
r
Check ignition timing
1. Malfunction of ECU
2. Malfunction of AC
Normal Abnormal
Clogged 1. Replace injector
Probable causes
Fault condition
Check and ad
j
ustment
1-14

1. General Information
E. Starter Motor Malfunction
1. Starter Motor doesn’t rotate
Check the battery circuit by
activating turning signal
Push the staring button and check if
the starting relay is activated
Flashing normally Not flashing or dimmed
Starting relay activated Starting relay not activated
Connect the starting motor to
the battery
Starter Motor rotates Starter Motor doesn’t rotate
1. Bad contact in the starter switch
2. Abnormal Starter relay
3. Loose coupler or terminals
Insufficient Batter
y
ca
p
acit
y
(60~120 flashes per minute)
1. Abnormal wire harness
1. Worn carbon brushes
2. Broken or shorted rotor windings
3. Broken Starter motor sub wire
4. Loose coupler
Braking light activated Braking light not activated
1. Burnt Fuse
2. Insufficient Battery Voltage
3. Abnormal braking switch
4. Abnormal main switch
Check and ad
j
ustment Fault condition Possible causes
Pull the brake handle or step
on the braking pedal
1-15