KYMCO AK 550 User manual

KYMCO Repair Manual AK 550
KYMCO AK 550 Service Manual
Using this manual
This manual has been designed to assist trained mechanics in servicing the
models listed above. If you do not have the proper training or tools to perform a
particular task it is best if you seek out a service professional.
This manual was written using the latest information available at the time of
publication. Illustrations in this manual are shown to help you with the basics of
performing the jobs listed. The pictures in this manual may not depict the actual
vehicle you’re working on, however the procedures will be similar.
Inexperienced technicians without the correct tools and knowledge may not be
able to perform these jobs as intended. Caution needs to be taken for the vehicle
and its operator as serious injury can occur. Always read a procedure in its
entirety before attempting any repairs.
1

KYMCO Repair Manual AK 550
KYMCO reserves all rights to this publication and does not permit the
reproduction or use of this publication, in full or in part, in any manner without our
express written permission. No trademark or patent liability is assumed with
respect to the use of the information contained in this manual.
While the instructions, photographs and illustrations in this manual have been
reviewed for accuracy it is up to the individual performing the procedures to use
good judgement when performing any procedures described. Every precaution
has been taken in the manufacture of this manual however the publisher
assumes no responsibility for errors and omissions. Furthermore, no liability or
responsibility is assumed for damages to property or injury to persons resulting
from the use of the information contained in this guide. Use of this information to
perform service procedures is done entirely at your own risk.
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KYMCO Repair Manual AK 550
1. Quick Reference
Component Location ..........................................................1-2
Special Tools .......................................................................1-5
Specifications ......................................................................1-7
Fuel Injection System .........................................................1-12
Fuel Injection System Failure Code ..................................1-13
Torque Specifications .........................................................1-15
Troubleshooting ..................................................................1-18
VIN and Engine Number Location .....................................1-23
2.Periodic Maintenance
Maintenance Schedule .......................................................2-2
Air Filter Servicing ..............................................................2-4
Brake Fluid ...........................................................................2-6
Brake Inspection .................................................................2-10
Coolant .................................................................................2-14
Engine Oil .............................................................................2-18
General Lubrication ............................................................2-23
Side Stand ............................................................................2-24
Spark Plug ............................................................................2-25
Engine Compression Test ..................................................2-27
Steering Inspection...............................................................2-28
Throttle Free Play ................................................................2-29
Parking Brake ......................................................................2-30
Light Inspection ..................................................................2-32
Tires ......................................................................................2-33
TPMS Tire Pressure Management System.........................2-34
Drive Belt Inspection ..........................................................2-39
Drive Belt Tension Adjustment ..........................................2-40
Valve Clearance Adjustment................................................2-45
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KYMCO Repair Manual AK 550
3.External Components
General Instructions........................................................................3-2
Dismantled and assembly order.....................................................3-3
Windscreen Cover/Windscreen/ Windscreen Holder....................3-4
Front Meter Cover/Back Mirror/Mats Of Floor And Leg Shield....3-5
Side Cover/Side Skirt Set................................................................3-6
Panel Floor .......................................................................................3-7
Seat...................................................................................................3-8
Luggage Box....................................................................................3-9
Center Cover B/Side Board A.........................................................3-10
Front Cover Set................................................................................3-11
Meter Cover Set ...............................................................................3-13
Leg Shield Set..................................................................................3-14
Front Inner Fender/Under Cowl Set................................................3-15
Front Fender Set..............................................................................3-16
Up And Low Handle Cover..............................................................3-17
Rear Carriers/Rear Center Cover....................................................3-18
Rear Fender Set...............................................................................3-19
Body Cover Set................................................................................3-20
Heat Shield.......................................................................................3-21
Exhaust System...............................................................................3-22
Muffler...............................................................................................3-23
Exhaust Pipe ....................................................................................3-24
O2 Sensor.........................................................................................3-25
Side Stand........................................................................................3-26
Center Stand ....................................................................................3-27
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KYMCO Repair Manual AK 550
4.Engine
General Instructions ......................................................................4-1
Troubleshooting .............................................................................4-2
Engine Torque Specifications .......................................................4-5
Cylinder Head Cover ......................................................................4-7
Camshaft .........................................................................................4-11
Cylinder Head .................................................................................4-16
Cylinder ...........................................................................................4-19
Piston ..............................................................................................4-20
CVT ..................................................................................................4-21
Left Side Cover ...............................................................................4-36
Fly Wheel ........................................................................................4-38
Mission Box ....................................................................................4-42
Crankcase .......................................................................................4-53
Crankshaft/Balancer Gear/Plane Bearing ....................................4-56
Plane Bearing Selection ................................................................4-57
Engine Removal .............................................................................4-62
5.Cooling System
General Instructions ......................................................................5-1
Troubleshooting .............................................................................5-2
Coolant ............................................................................................5-3
Radiator ..........................................................................................5-7
Water Temperature Sensor (WTS) ................................................5-11
Water Pump ....................................................................................5-16
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KYMCO Repair Manual AK 550
6.Fuel Injection System
GENERAL INSTRUCTIONS ............................................................6-2
TROUBLESHOOTING .....................................................................6-3
COMPONENT LOCATION ..............................................................6-4
ECU .................................................................................................6-7
IGNITION COIL ...............................................................................6-9
SPARK PLUG .................................................................................6-10
CRANK POSITION SENSOR ..........................................................6-12
O2 SENSOR ....................................................................................6-13
RELAYS ..........................................................................................6-14
FUEL TANK .....................................................................................6-15
FUEL PUMP ....................................................................................6-21
FUEL INJECTOR ............................................................................6-27
THROTTLE BODY ...........................................................................6-32
T-MAP SENSOR .............................................................................6-36
TPS SENSOR....................................................................................6-37
ISC.....................................................................................................6-38
TILT SWITCH ..................................................................................6-40
WATER TEMPERATURE SENSOR ................................................6-42
SELF-DIAGNOSIS ............................................................................6-43
DIAGNOSTIC TOOL ........................................................................6-34
FAILURE CODE................................................................................6-50
DIAGNOSTIC REPORT ....................................................................6-57
7.CVT Continuously Variable Transmission
General Instructions ......................................................................7-1
Troubleshooting .............................................................................7-1
Schematic Drawing ........................................................................7-2
Belt Case .........................................................................................7-3
CVT Removal ..................................................................................7-8
Driven Pulley Disassembly ...........................................................7-10
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KYMCO Repair Manual AK 550
8.Final Drive
SCHEMATIC DRAWING .................................................................8-1
TROUBLESHOOTING .....................................................................8-2
FINAL REDUCTION ........................................................................8-3
9.Electrical Systems
General Instructions........................................................................9-1
Troubleshooting ..............................................................................9-3
Component Location.......................................................................9-8
Fuses ...............................................................................................9-12
ECU ................................................................................................9-13
Ignition System ..............................................................................9-15
Spark Plug ......................................................................................9-16
Charging System ...........................................................................9-19
Battery .............................................................................................9-23
Starting System ..............................................................................9-25
Relays .............................................................................................9-27
Switches .........................................................................................9-28
Lights ..............................................................................................9-42
Grip Heater .....................................................................................9-50
Horn .................................................................................................9-54
Meter Instrument ............................................................................9-55
noodoe Meter .................................................................................9-56
Tire Pressure Management System ..............................................9-58
Tire Pressure Management System ..............................................9-58
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KYMCO Repair Manual AK 550
10.Brakes
GENERAL INSTRUCTIONS ............................................................10-1
TROUBLESHOOTING .....................................................................10-2
DIAGRAM ........................................................................................10-3
Brake Pad Replacement ................................................................10-4
MASTER CYLINDERS......................................................................10-11
BLEED THE BRAKE FLUID ...........................................................10-12
PARKING BRAKE ............................................................................10-18
DISC BRAKE ...................................................................................10-19
ABS SYSTEM ..................................................................................10-20
ABS TROUBLESHOOTING OUTLINE ...........................................10-25
11.Steering
TROUBLESHOOTING .....................................................................11-2
Up And Low Handle Cover Removal ............................................11-2
Handlebar .......................................................................................11-3
Switch Housings and Throttle ......................................................11-4
Grips ................................................................................................11-9
Steering stem .................................................................................11-10
12.Front Suspension
TROUBLESHOOTING .....................................................................12-1
Front Fender Assy. Removal ........................................................12-2
Front Fork Removal .......................................................................12-3
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KYMCO Repair Manual AK 550
13.Rear Suspension
TROUBLESHOOTING ......................................................................13-1
Rear CUSHION .................................................................................13-2
Rear Wheel Removal .......................................................................13-3
Drive Belt Inspection.......................................................................13-13
Drive Belt Installation......................................................................13-14
Rear Fork..........................................................................................13-19
14.Wheels
This chapter covers the location and servicing of the wheels for the KYMCO AK
550 model.
Troubleshooting .............................................................................14-1
Front Wheel ....................................................................................14-2
Front Fender Assy. Removal ........................................................14-2
Front Wheel Disassembly .............................................................14-6
Bearing Replacement ....................................................................14-9
Rear Wheel .....................................................................................14-11
Rear Wheel Inspection ...................................................................14-17
Rear Wheel Installation ..................................................................14-22
Tire Pressure Sensor.......................................................................14-28
15.EEC SYSTEM
E.E.C System Introduction .................................................15-2
Function ...............................................................................15-3
Trouble Shooting .................................................................15-3
Air Filter Servicing ..............................................................15-4
Maintenance Information ....................................................15-5
Dismantle Of Canister .........................................................15-6
Oxygen Sensor ....................................................................15-9
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1.Quick Reference AK 550
1-1
1. Quick Reference
This chapter provides a quick reference source of technical specifications and
information for KYMCO AK 550 model.
Component Location ..........................................................1-2
Special Tools .......................................................................1-5
Specifications ......................................................................1-7
Fuel Injection System Failure Code ..................................1-12
Torque Specifications .........................................................1-14
Troubleshooting ..................................................................1-17
VIN and Engine Number Location .....................................1-22

1.Quick Reference AK 550
1-2
Component Location
Regulator/Rectifier
Hazard Controller
ECU
Ignition Coil/Spark Plug
Coolant Reserve Tank
Ignition Switch
Radiator
Keyless & Seat
Open Controller
Diagnostic Tool Connector
Fuel Tank
Air Cleaner/Element
Canister
Muffler
Rear Wheel Speed
Sensor Connector
Horn
Tire Pressure Controller
ISC
Meter Instrument Couplers
FUSE BOX
O2 Sensor
Side Standard Switch
Seat Open Motor

1.Quick Reference AK 550
1-3
Component Location
Throttle Body
TPS
Fuel Injector
Fuel Pump
T-MAP Sensor
Fuel Cap
Thermostat
T-MAP Sensor (Air Cleaner)

1.Quick Reference AK 550
1-4
Component Location
Radiator Cap
Winker Relay
(Turn Signal)
ECU
Tilt Switch
ABS ECU
Heater Grip Controller
Battery
Fuel Pump Relay
Fan Relay
Seat Relay
Main Relay
Starter Relay

1.Quick Reference AK 550
1-5
Special Tools
NO.
NAME
Illustration
E039 A120 E00039 CYLINDER COMPRESSION GAUAGE
E048 A120 E00048 FUEL PRESSURE GAUAGE
E053 A120 E00098 CLUTCH SPRING COMPRESSOR(E053*E028)
E056 A120 E00017 UNIVERSAL HOLDER
E058 A120 E00021 DRIVE PULLEY HOLDER
E064 A120 E00014 OIL SEAL & BEARING INSTALLER
E084 A120 E00084 FLYWHEEL PULLER
E085 A120 E00085 INJECTOR CLEANER
E090 A120 E00090 WIRES INJECTOR CONNECTOR
CODE

1.Quick Reference AK 550
1-6
NO.
NAME
Illustration
E093 A120 E00093 BEARING PULLER
F002 A120 F00002 STEERING STEM LOCK NUT WRENCH
F023 A120 F00023 STEERING STEM TOP THREAD WRENCH
F030 A120 F00030 BAND REMOVER/INSTALLER
F031 A120 F00031 PLIERS FUEL PIPE
F032 A120 F00032 ELECTRIC REPAIR KIT
F033 A120 F00033 DIGITAL ELECTRIC GAUGE
F034 A120 F00034 VACUUM PUMP
F035 A120 F00035 RADIATOR PRESSURE GAUAGE
F038 A120 F00038 REAR WHEEL HUB & DISK REMOVER
CODE

1.Quick Reference AK 550
1-7
KYMCO AK 550 Specifications
General Information
Name (Model Code) AK 550 (LGC6)
Overall length (mm) 2165±20
Overall width (mm) 795±20
Overall height (mm) 1400±20
Wheel base (mm) 1580±10
Engine type 4 stroke DOHC
Displacement (cc) 550
Fuel recommended 90 # nonleaded gasoline
Curb weight (kg)
Front wheel 110±4
Rear wheel 116±4
Total 226±4
Max. weight capacity (kg)
Front wheel 177
Rear wheel 218
Total 395
Tires
Front wheel 120/70-R15
Rear wheel 160/60-R15
Ground clearance (mm) 140
Performance
Braking distance (m) 12.3m / 50 km/hr
Min. turning radius (m) 2.7

1.Quick Reference AK 550
1-8
Engine
Starting system Starting motor
Type Gasoline, 4-stroke
Cylinder arrangement TWIN CYLINDER
Combustion chamber type Semi-sphere
Valve arrangement D.O.H.C. Chain drive
Bore x stroke (mm) 69 x 73.6
Compression ratio 11
Compression pressure 19 (kg/cm2)
Max. Horsepower M1:53/7500 PS/rpm
M2:46/7000 PS/rpm
Max. Torque 5.4/6000 Kg-m/rpm
Valve timing
Intake
Open 16° BTDC
Close 30° ABDC
Exhaust
Open 35° BBDC
Close 3° AT D C
Valve clearance (cold) (mm)
Intake 0.175
Exhaust 0.225
Idle speed (rpm) 1200 ± 100
Lubrication System
Lubrication type Forced pressure & Dry sump
Oil pump type Inner/outer rotor type
Oil filter type Full-flow filtration
Oil capacity Exchanging capacity 2.6 liter
Total capacity 3.0 liter
Cooling Type Liquid cooling

1.Quick Reference AK 550
1-9
Fuel System
Air cleaner type & No Paper element, wet
Fuel capacity 14.5 liter
Injection
Brand Synerjet
Type Throttle body
Venturi dia.(mm) 34
Fuel pump pressure 3 Bar
Electrical
Equipment
Ignition System
Type ECU
Spark plug
Spec.
CR7E (NGK)
Gap 0.7~0.8 mm
Battery Capacity 12V11AH
Power Drive System
Clutch Type Wet multi disk
Transmission
Gear
Type CVT
Operation Automatic centrifugal type
Reduction Gear
Type Two-stage reduction
Reduction
ratio
1st 0.8 ~2.4
2nd 2.659
Moving Device
Tire type Tubeless
Wheel material Aluminum
Tire pressure
Kgf/cm2
Front 2.35
Rear 2.7
Handle turning angle(L/R)
Left 40°
Right 40°
Brake system type
Front
Disc brake
Rear Disc brake
Damping Device
Suspension type
Front
Telescope Upside-down
Fork
Rear Swing arm
Shock absorber stroke
Front
120 mm
Rear 48 mm
Frame type UNDER BONE

1.Quick Reference AK 550
1-10
ENGINE
Throttle grip free play 2 ~ 6 mm
Spark plug NGK: CR7E
Spark plug gap 0.7 mm ~ 0.8 mm
Valve clearance IN: 0.175 mm EX: 0.225 mm
Idle speed 1200 ± 100 rpm
Compression ratio 11 ± 0.2
Ignition timing ECU
Coolant type Liquid cooling
Engine oil capacity:
At disassembly 3 Liter
At change 2.6 Liter
Coolant capacity:
Radiator with cool coolant 1200 cc
Reserve tank 300 cc

1.Quick Reference AK 550
1-11
Cooling System
Radiator cap relief pressure 0.9 ± 0.15 kg/cm2 (12.8 ± 2.1 psi)
Thermostat temperature
Begins to open 80-84 °C
Full-open 95 °C
Valve lift 5 mm
COOLANT GRAVITY CHART
Temp.℃
Concentration
0 5 10 15 20 25 30 35 40 45 50
5 1.009 1.009 1.008 1.008 1.007 1.006 1.005 1.003 1.001 0.999 0.997
10 1.018 1.017 1.017 1.016 1.015 1.014 1.013 1.011 1.009 1.007 1.005
15 1.028 1.027 1.026 1.025 1.024 1.022 1.020 1.018 1.016 1.014 1.012
20 1.036 1.035 1.034 1.033 1.031 1.029 1.027 1.025 1.023 1.021 1.019
25 1.045 1.044 1.043 1.042 1.040 1.038 1.036 1.034 1.031 1.028 1.025
30 1.053 1.051 1.051 1.049 1.047 1.045 1.043 1.041 1.038 1.035 1.032
35 1.063 1.062 1.060 1.058 1.056 1.054 1.052 1.049 1.046 1.043 1.040
40 1.072 1.070 1.068 1.066 1.064 1.062 1.059 1.056 1.053 1.050 1.047
45 1.080 1.078 1.076 1.074 1.072 1.069 1.056 1.063 1.062 1.057 1.054
50 1.086 1.084 1.082 1.080 1.077 1.074 1.071 1.068 1.065 1.062 1.059
55 1.095 1.093 1.091 1.088 1.085 1.082 1.079 1.076 1.073 1.070 1.067
60 1.100 1.098 1.095 1.092 1.089 1.086 1.083 1.080 1.077 1.074 1.071