Sym PA12B User manual

PA12B
PA12C
SERVICE MANUAL
FOREWORD CONTENTS
HOW TO USE THIS MANUAL MECHANICAL LAYOUT

Foreword
Homepage Contents
This service manual contains the technical data of each component inspection and
repair for the SANYANG PA12B & PA12C 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, PA12B & PA12C 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.

How To Use This Manual
Homepage Contents
This service manual describes basic information of individual parts and system
inspection & service for SANYANG PA12B&PA12C 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 to the 12th chapters contain the parts of vehicle frame.
The 13th chapter is electrical appliances.
The 15th chapter is wiring diagram.
Please see index of content for brief information and quick guide.
There are 4 buttons, “Foreword”, “Contents”, “How to Use This Manual” and
“Mechanical Layout” on the PDF version homepage, and can access these items
by clicking of the mouse.
If technician wants to see the content of one specific chapter, click on the title of
each chapter on the Index page. There are two buttons on the upper part of each
page, “Homepage” and “contents”. The user can click on the “Homepage” button or
the “Contents” button to go back to the homepage or contents index. Therefore, to
check one paragraph inside the chapter, click on the paragraph index to go to the
desired paragraph. In addition, there is a “To This Chapter Contents” button at the
upper side of each page, by clicking the button; you can go back to the paragraph
selection index of this specific chapter.

Homepage
Contents
Page Content Index
1-1 ~ 1-20 General Information
1
2-1 ~ 2-24 Maintenance Information
2
3-1 ~ 3-14 Fuel System 3
4-1 ~ 4-18 Lubrication / Clutch / Transmission 4
5-1 ~ 5-8 AC Generator / Starter Clutch 5
6-1 ~ 6-8 Engine Removal 6
7-1 ~ 7-18 Cylinder Head / Valve 7
8-1 ~ 8-10 Cylinder / Piston 8
9-1 ~ 9-16 Crankshaft / Crankcase / Shifting Gear / Kick Starter 9
10-1 ~ 10-14 Brake System 10
11-1 ~ 11-22 Steering / Front Wheel / Front Fork 11
12-1 ~ 12-16 Rear Wheel / Rear Cushion / Swingarm 12
13-1 ~ 13-26 Electrical System 13
14-1 ~ 14-10 Emission Control System 14
15-1 ~ 15-2 Wiring Diagram 15

Homepage Contents
Mechanical Layout
RR brake pedal
Headlight/starting
/Hazard switch Kick-starter
Engine Oil Dipstick
FR winker
Air filter
Fuel tank cap
RR. winker
C.D.I.
Headlight dimmer
switch/Signal light
/ Horn switch
Regulator/
Rectifier
Tail light
Battery/ Fuse
Ignition coil
Winker relay
Headlight
Shifting pedal
Choke lever
Main Switch
FR Brake lever
Clutch lever
Muffler

Homepage Contents
1. General Information
Symbols and Marks···················1-1
General Safety···························1-2
Service Precautions··················1-3
Specifications····························1-9
Torque Values ···························1-11
Trouble Diagnosis·····················1-13
Lubrication Points·····················1-19
1
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 is procedures 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 go through
the component (invisibility).
1-1

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1. General Information
General Safety BatteryCarbon monoxide
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 an 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 an air hose 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.

To this chapter contents
1. General Information
Service Precautions
yAlways use with SANYANG genuine parts and
recommended oils. Using non-genuine parts for
SANYANG vehicle may damage it.
1-3
ySpecial tools are designed for remove and
install of components without damaging the part.
Using wrong tools may result in damage.
yWhen servicing this bike, use only metric tools.
Metric bolts, nuts, using wrong tools and
fasteners may damage this vehicle.
yClean 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.
yWash and clean parts with high ignition point
solvent, and blow-dry with compressed air. Pay
special attention to O-rings or oil seals because
most cleaning agents have an adverse effect on
them.
yNever bend or twist a control cable to prevent
unsmooth control and premature worn out.
yRubber 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.
yWhen 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.
yStore complex components such as
transmission parts in the proper assemble order
and tie them together with a wire for ease of
installation later.
yNote the reassemble position of the important
components before disassembling them to
ensure they will be reassembled in correct
dimensions (depth, distance or position).
yComponents not to be reused should be
replaced when disassembled including gaskets
metal seal rings, O-rings, oil seals, snap rings,
and split pins.

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1. General Information
yThe length of bolts and screws for assembly,
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 out side 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
yTighten 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.
yWhen oil seal is installed, 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.
yRemove residues of the old gasket or sealant
before reinstallation, grind with a grindstone if
the contact surface has any damage.
yThe 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
Connector
yRubber and plastic boots should be properly
reinstalled to the original correct positions as
designed.
Boots
yThe 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
To this chapter contents
yLubricate the rotation face with specified
lubricant on the lubrication points before
assembling.
1-5
yCheck if positions and operation for installed
parts is in correct and properly.
yMake sure service safety each other when
conducting by two persons.
yNote that do not let parts fall down.
yBefore 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.
yAfter service completed, make sure all
connection points is secured.
Battery positive (+) cable should be connected
firstly.
yAnd the two posts of battery have to be greased
after connected the cables.
yMake sure that the battery post caps are
located in properly after the battery posts had
been serviced.
yIf fuse burned, it has to find out the cause and
solved it. And then replace with specified
capacity fuse.
Capacity
verification

To this chapter contents
1. General Information
yWhen separating a connector, it locker has to
be unlocked first. Then, conduct the service
operation.
1-6
yDo not pull the wires as removing a connector
or wires. Hold the connector body.
yMake sure if the connector pins are bent,
extruded or loosen.
yInsert 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.
yCheck if the connector is covered by the twin
connector boot completely and secured
properly.
yBefore terminal connection, check if the boot is
crack or the terminal is loose.
yInsert the terminal completely.
Check if the boot covers the terminal.
Do not let boot open facing up.
ySecure 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.
yWire band and wire harness have to be
clamped secured properly.
yDo not squeeze wires against the weld or its
clamp.

1. General Information
To this chapter contents
yDo not let the wire harness contact with rotating,
moving or vibrating components when routing
the harness.
1-7
yKeep wire harnesses far away from the hot
parts.
yAvoid wire harnesses from sharp edges or
corners, and also avoid the jutted-out ends of
bolts and screws.
yRoute harnesses so that they neither pull too
tight nor have excessive slack.
yProtect 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.
ySecure the rubber boot firmly as applying it on
wire harness.
Never Touch
yNever use wires or harnesses which insulation
has been broken. Wrap electrical tape around
the damaged parts or replace them.
yNever clamp or squeeze the wire harness when
installing other components.
Never clamp or
squeeze the wire
harness
Never too tight

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1. General Information
yDo not let the wire harness been twisted when
installation.
1-8
yWire 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.
yBefore operating a test instrument, operator
should read the operation manual of the
instrument. And then, conduct test in
accordance with the instruction.
yUse sand paper to clean connector
pins/terminals if rust is found. And then
continue the connection operation.
Clean rust
Do you know how to set the
instrument to its
measurement position and
the insert locations of its
two probes?

1. General Information
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Specifications
MAKER SANYANG MODEL PA12B
Overall Length 1910 mm Front TELESCOPIC FORK
Overall Width 760 mm
Suspension
System Rear SWING ARM
Overall Height 1030 mm Front 2.75-18-4PR
Dimension
Wheel Base 1210 mm
Tire
Specifications Rear 3.00-17-4PR
Front 53 kg
Rear 70 kg Front DISK (ø 240 mm)
Curb
Weight
Total 123 kg
Brake System
Rear DRUM (ø 130 mm)
Passengers/Weight Two / 110 kg Max. Speed Above 94 km/hr
Front 75 kg Performance
Climb Ability Below 28°
Rear 158 kg Primary
Reduction 4.06
Weight
Total
Weight
Total 233 kg Secondary
Reduction 2.73
Type Air cooled 4-stroke
gasoline engine Clutch wet mutiplate
Installation and
arrangement Vertical, below center,
incline 15°
Reduction
Transmission 5 speed, circulated
Fuel Used Above 92 unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/ forced air
cooled Horn 80~112 dB/A
Bore Ø 56.5 mm Muffler Expansion & Pulse
Type
Stroke 49.5 mm Exhaust Pipe Position and
Direction Right side, and
Backward
Cylinder
Number/Arrange
ment SINGLE CYLINDER Lubrication System forced and wet sump
Displacement 124 cc Solid Particulate -
Compression Ratio 9: 1 CO Below 3.0 %
Max. HP 12.5 ps / 9500 rpm
Exhaust
Concentratio
n
HC+Nox Below 2000 PPM
Max. Torque 1.0 kg-m / 7500 rpm E.E.C. √
Ignition C.D.I. P.C.V. √
Engine
Starting System kick & electrical
starter Catalytic reaction control
system √
1-9

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1. General Information
MAKER SANYANG MODEL PA12C
Overall Length 1940 mm Front TELESCOPIC FORK
Overall Width 715 mm
Suspension
System Rear SWING ARM
Overall Height 1085 mm Front 2.75-18-4PR
Dimension
Wheel Base 1235 mm
Tire
Specifications Rear 3.00-17-4PR
Front 52.5 kg
Rear 66 kg Front DISK (ø 240 mm)
Curb
Weight
Total 118.5 kg
Brake System
Rear DRUM (ø 130 mm)
Passengers/Weight Two / 110 kg Max. Speed Above 94 km/hr
Front 75 kg Performance
Climb Ability Below 28°
Rear 158 kg Primary
Reduction 4.06
Weight
Total
Weight
Total 228.5 kg Secondary
Reduction 2.73
Type Air cooled 4-stroke
gasoline engine Clutch wet mutiplate
Installation and
arrangement Vertical, below center,
incline 15°
Reduction
Transmission 5 speed, circulated
Fuel Used Above 92 unleaded Speedometer 0 ~ 140 km/hr
Cycle/Cooling 4-stroke/ forced air
cooled Horn 80~112 dB/A
Bore Ø 56.5 mm Muffler Expansion & Pulse
Type
Stroke 49.5 mm Exhaust Pipe Position and
Direction Right side, and
Backward
Cylinder
Number/Arrange
ment SINGLE CYLINDER Lubrication System forced and wet sump
Displacement 124 cc Solid Particulate -
Compression Ratio 9: 1 CO Below 3.0 %
Max. HP 12.5 ps / 9500 rpm
Exhaust
Concentratio
n
HC+Nox Below 2000 PPM
Max. Torque 1.0 kg-m / 7500 rpm E.E.C. √
Ignition C.D.I. P.C.V. √
Engine
Starting System kick & electrical
starter Catalytic reaction control
system √
1-10

1. General Information
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Torque Values
The torque values listed in above table are for more important tighten torque values. Please see standard
alues for those not listed in the table.v
Standard Torque Values for Reference
Type Tighten Torque Type Tighten Torque
5 mm bolt、nut 0.45~0.6kgf-m 4 mm screw 0.10~0.15kgf-m
6 mm bolt、nut 0.8~1.2kgf-m 5 mm screw 0.35~0.5kgf-m
8 mm bolt、nut 1.8~2.5kgf-m 6 mm screw、SH nut 0.7~ 1.10kgf-m
10 mm bolt、nut 3.0~4.0kgf-m 6 mm bolt、nut 1.0 0~1.40kgf-m
12 mm bolt、nut 5.0~6.0kgf-m 8 mm bolt、nut 2.40 ~3.00kgf-m
3 mm screw 0.05~0.08kgf-m 10 mm bolt、nut 3.50~4.50kgf-m
Engine Torque Values
Item Q’ty Thread Dia. (mm) Torque Value(kgf-m) Remarks
Cylinder head nut 4 8 2.8~3.0
Cylinder head left bolt 1 6 0.8~1.2
Cylinder stud bolt 4 8 0.7~1.0
Cylinder head side cover bolt 2 6 0.8~1.2
Cylinder head cover bolt 2 30 1.3~1.7
Cylinder head stud bolt (inlet pipe) 2 6 1.0~1.4
Cylinder head stud bolt (EX. pipe) 2 8 2.4~3.0
Air inject pipe bolt 4 6 1.0~1.4
Air inject reed valve bolt 2 3 0.07~0.09
Tappet adjustment screw nut 4 5 0.7~1.1 Apply oil to thread
Spark plug 1 10 1.0~1.2
Tensioner lifter bolt 2 6 1.0~1.4
Carburetor insulator bolt 2 6 0.7~1.1
Oil pump screw 2 6 0.3~0.4
1 7 1.0~1.4
Engine left cover bolt 9 6 1.1~1.5
Engine oil draining bolt 1 12 3.5~4.5
Engine oil strainer cap 1 30 1.3~1.7
Mission draining bolt 1 8 0.8~1.2
Mission filling bolt 1 10 1.0~1.4
Clutch driving plate nut 1 28 5.0~6.0
Clutch outer nut 1 14 5.0~6.0
Drive face nut 1 14 8.5~10.5
ACG. Flywheel nut 1 14 5.0~6.0
Crankcase bolt 7 6 0.8~1.2
Mission case bolt 7 8 2.6~3.0
Muffler mounting bolt 3 10 3.2 ~3.8
Muffler mounting nut 2 8 1.0 ~1.2
1-11

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1. General Information
Frame Torque Values
Item Q’ty Thread Dia. (mm) Torque Value (Kg-m) Remarks
Mounting bolt for steering handle
post 4 8 3.0~3.5
Lock nut for steering stem 1 BC1 1.0~2.0
Steering top cone race 1 BC1 2.0~3.0
Front wheel axle nut 1 12 5.0~7.0
Rear wheel axle nut 1 16 11.0~13.0
Front cushion mounting bolt 4 10 3.5~4.5
Rear cushion upper connection bolt 1 10 3.5~4.5
Rear cushion under connection bolt 1 8 2.4~3.0
Rear fork mounting bolt 2 10 4.0~5.0
Brake hose bolt 2 10 3.0~4.0
Brake air-bleeding valve 1 6 0.8~1.0
Front brake disc mounting bolt 5 8 4.0~4.5
Rear brake disc mounting bolt 5 8 4.0~4.5
Brake clipper mounting bolt 2 8 2.9~3.5
Engine hanger link bolt 2 12 7.5~9.5 On frame side
Engine hanger link nut 1 12 7.5~9.5 On engine side
Main standard nut 1 10 4.0~5.0
Air cleaner bolts 2 6 1.0~1.4
1-12

1. General Information
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Troubles Diagnosis
A. Engine hard to start or can not be started
1-13
Check and adjustment Fault condition Possible causes
Loosen carburetor drain bolt
to check if there is gasoline
inside the carbureto
r
Fuel supplied to
carburetor sufficient
1. No fuel in fuel tank
2. Check if the pipes, fuel tank to carburetor
and intake vacuum, are clogged.
3. Float valve clogged
4. Lines in fuel tank evaporation system
clogged
5. Malfunction of fuel pump
6. Loosen or damaged fuel pump vacuum
hose
7. Fuel filter clogged
Remove spark plug, install it
into spark plug cap, and
perform a spark test.
Perform cylinder
compression pressure test.
Good sparks Weak sparks, no spark
at all
Cylinder compression
pressure normal
1. Malfunction of spark plug
2. Spark plug damaged
3. Malfunction of CDI set
4. Malfunction of AC generator
5. Ignition coil is in open or short circuit
6. Ignition coil wire open or short circuit
7. Main switch malfunction
Low compression
pressure or no pressure
Re-start by following the
starting procedures
No ignition
1. Piston ring seized
2. Malfunction of cylinder valves
3. Worn cylinder and piston ring
4. Cylinder gasket leak
5. Sand hole in compression parts
There are some signs of
ignition; but engine
cannot be started
Remove the spark plug again
and check it.
Dry spark plug
1. Fuel level in carburetor too high
2. Malfunction of throttle valve operation
3. Throttle valve opening too wide
1. Malfunction of throttle valve operation
2. Air leaking through intake manifold
3. Incorrect ignition timing
Wet spark plug
No fuel is supplied to
carburetor
Start with choke applied

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1. General Information
B. Engine run sluggish (Speed does not pick up, lack of power)
1-14
Check and adjustment Fault condition Possible causes
Try gradual acceleration and
check engine speed
Engine speed increases.
1. Air cleaner clogged
2. Poor fuel supply
3. Lines in fuel tank evaporation system
clogged
4. Exhaust pipe clogged
5. Fuel level too low in carburetor
6. Fuel nozzle clogged in carburetor.
Check ignition timing
(Using ignition lamp)
Engine speed cannot
increase.
Check cylinder compression
pressure (using compression
pressure gauge)
Ignition timing correct Incorrect ignition timing
Compression pressure
correct
1. Malfunction of CDI
2. Malfunction of AC alternator
No compression pressure
Check if carburetor jet is
clogged
No clogged 1. Remove foreign
1. Cylinder & piston ring worn out
2. Cylinder gasket leaked
3. Sand hole in compression parts
4. Valve deterioration
5. Seized piston ring
Remove spark plug
Check if engine over heat
No foul or discoloration Fouled and discoloration
No knock Knock
1. Remove dirt
2. Incorrect spark plug heat range
1. Piston and cylinder worn out
2. Lean mixture
3. Poor fuel quality
4. Too much carbon deposited in
combustion chamber
5. Ignition timing too advanced
6. Poor circuit on the cooling system
Normal Engine overheat
Continually drive in
acceleration or high speed
1. Too much carbon deposited in
combustion chamber
2. Lean mixture
3. Poor fuel quality
4. Ignition timing too advanced
Clogged

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1. General Information
C. Engine runs sluggish (especially in low speed and idling)
D. Engine runs sluggish (High speed)
Check and ad
j
ustment Fault condition Probable causes
Check ignition timing
(Using ignition lamp)
Check for fuel supplying
system in automatic fuel cup
Check if carburetor clogged
1. Incorrect ignition timing (malfunction
of CDI or AC alternator)
1. Rich mixture (loosen the screw)
2. Lean mixture (tighten the screw)
1. Poor heat insulation gasket
2. Carburetor lock loose
3. Poor intake gasket
4. Poor carburetor O-ring
5. Vacuum hose crack
1. Spark plug fouled
2. Malfunction of CDI
3. Malfunction of AC generator
4. Malfunction of ignition coil
5. Open or short circuit in spark plug
leads
6. Malfunction of main switch
1. Insufficient fuel in fuel tank
2. Fuel filter clogged
3. Restricted fuel tank vent
Good Poor
1. Malfunction of CDI
2. Malfunction of AC alternator
Normal Abnormal
Check and adjustment Fault condition Probable causes
Check ignition timing
Good spark Poor
Remove spark plug, install
spark plug into spark plug
cap and perform spark test
against engine ground
No air sucked
Air sucked through
carburetor gasket
Good Poor
Adjust the air screw of
carburetor
Normal Abnormal
Air sucked
No clogged Clogged 1. Cleaning
1-15