ADLY MOTO GK-125R User manual

SERVICE MANUAL
GK-125R【92/61】
July 04
High Power Engine
HER CHEE INDUSTRIAL CO., LTD.

Preface
The Service Manual in reference is provided as the technical
information for checking and preparation of ADLY GK-125R
GO-KART and the edit description is given in diagrams with " Operation
Sequence ", " Highlights " and " Checking Arrangement " for reference of
the service staffs.
The information, illustrations or contents included in this manual may
be different with the actual scooter in case specifications are changed.
Your understanding will be appreciated.
HER CHEE INDUSTRIAL CO., LTD.

I N D E X
Informationforpreparation 1
Muffler,Coverparts 2
CheckandAdjust 3
Lubricantsystem 4
Fuelsystem 5
Removeofengine 6
Cylinderhead,Valve 7
Cylinder,Piston 8
Transmission, Kick start 9
Finaltransmission 10
Crankcase,Crankshaft 11
Front wheel, Brake, Suspension, steering 12
Rearwheel,Brake,Suspension 13
Battery, Charge, and Ignition system 14
Startingsystem 15
Wiringdiagram 16

ASSEMBLY INSTRUCTION
(For GK-125R )
1. Take out the battery and fill with acid liquid. Pre-charge the battery will extend
its life. The preparation and charge procedure is based on the battery’s
instruction.
2. Install the rear wheels and parts in the following order:
A. 16x40x5mm washer.
B. 16mm hex-bolt (torque 750~950 kg-cm, 74~93 N-m).
C. Cotter pin (open up the end after installed).
D. Rubber cap.
3. Install the front wheels and parts in the following order:
A. 12x40x4.5mm washer.
B. 12mm hex-bolt (torque 300~350kg-cm, 29.5~34N-m).
C. Cotter pin (open up the end after installed).
D. Rubber cap.
4. Install the battery with the red wire to positive (+) and black wire to the negative
(-). After the battery is connected, put the plastic cover on it. Place the steel
bracket over the cover and tie up with 2 hex-bolts.
5. Install the fuel tank on the rear rack and fuel valve on the frame. Fill up with
unleaded fuel and turn the fuel valve to ON position.
6. Install the seat from front. Pull the lock lever under the seat and fit into the seat rail.
Push back to set into proper position and release the lock lever.
7. Install the L/R roller cage tube started from the front of frame. Push the clip on the
frame and set tube onto the frame. Install the rear tube to the frame.
8. Install the top roller cage cross tube. The shorter tube is in the front and longer one
for the rear. Tie-up 4 hex-bolts to fix the top roller cage cross bar and 4
hex-socket bolts to fix the L/R tube on the frame.
9. Turn on the main switch and try to start the engine. In order to use the electric
starter, you need to check the following:
A. Step on the brake pedal for safety.
B. Turn the main switch to right in order to start the engine.
C. Do not continue to start up the engine for more then 10 seconds.

P.D.I. (Pre-Delivery Inspection)
(For GK-125R )
1. Record the frame and engine number into the owner’s manual.
2. Check that all tires have correct pressure specified on the tire
or in the owner’s manual.
3. Engine oil ( 4 stroke, 10W/40 ) is enough.
4. Battery is installed properly.
5. All brake cables are adjusted properly.
6. Fuel tank has enough gasoline to operate.
7. Check the suspension and drive chain for proper setup.
8. Check that all electrical components and lights are working
properly.
9. Make sure that the owner’s manual and tool bag are installed properly.

1-1
INFORMATION FOR PREPARATION
Attention on Operation
zAll washers, oil rings, clamp rings, opening pins shall be duly replaced by a new item
when dismounted.
zLocking of all screws, nuts, cross screws shall be performed in the order of first the large
screws and then the small ones and from inside to outside in opposite angles by tightening
the torque locks.
zAll items must use original parts, pure oil and greases.
zAll service shall use special tools and general tools to repair.
zAll dismounted items requiring for checks shall be duly cleaned and for assembly, all
items shall be duly lubricated.

1-2
INFORMATION FOR PREPARATION
Attention on Operation
zCertified lubricants in cans shall be used on all the elements to be lubricated.
zAfter assembly, performance of all elements shall be duly checked and the locking shall
be duly verified.
zIn case of an operation is performed by over 2 people, the assignment shall be conducted
in coordination and safety shall be the first priority.
zDefinition of signs:
The sign given in the Service Manual shall refer to the operation methods and observation.
OIL：lubrication by designated lubricant
GREASE： Lubrication by grease
Special Tool：Parts on which special tools shall be used
General Tool：General tools shall be used
New：Replace by new items after dismounting
Attention
Dangerous and important operations

1-3
INFORMATION FOR PREPARATION
SPECIFICATION
TYPE GK-125R
LENGTH 1780 mm
WIDTH 675 mm
HEIGHT 1160 mm
WHEEL BASE 1255 mm
NET WEIGHT 160 kg
ENGINE TYPE 4-STROKE, Single Cylinder
COOLING AIR COOLED
DISPLACEMENT 124 C.C.
BORE×STROKE 52.4×57.8
COMPRESSION RATIO 9.2:1
IGNITION C.D.I
STARTER ELECTRIC / KICK
SUSPENSION Hydraulic Shock Absorber
TRANSMISSION AUTOMATIC
TIRE Front 18*7-7
Rear 18*9.5-8
BRAKE Front: Drum Rear: Disc

1-4
INFORMATION FOR PREPARATION
LOCKING TORQUE
The standard locking torque shall apply in case of no specification.
STANDARD TORQUE：
Type Locking Torque (kg-m) Type Locking Torque (kg-m)
5mm Bolt, Nut 0.5 5 mm Screw 0.4
6mm Bolt, Nut 1.0 6 mm Screw 0.9
8mm Bolt, Nut 2.2 6 mm Face Bolt, Nut 1.2
10mm Bolt, Nut 3.5 8 mm Face Bolt, Nut 2.7
12mm Bolt, Nut 5.5 10 mm Face Bolt, Nut 4.0
CHASSIS：
Locking Place Quantity Dia. (mm) Torque (kg-m) Remark
Handle bar bottom flange nut 1 14 8 Nylon insert type
Ball joint fixed nut 4 10 4.0 Nylon insert type
Engine mounting flange nut 4 8 3.5
Engine mounting bracket bolt 2 10 4.0
Foot rest flange bolt 6 8 4.0
Rear swing arm fixed nut 1 14 9 Nylon insert type
Rear brake panel flange bolt 4 12 7
Front suspension fixed nut 4 10 4.0 Nylon insert type
Rear suspension flange bolt 2 10 4.0
Front rim nut 2 12 7
Rear rim nut 2 16 11
ENGINE：
Locking Place Quantity Dia. (mm) Torque (kg-m) Remark
Cylinder Head Bolt A 1 8 0.9 Stud bolt side
Cylinder Head Bolt B 1 8 0.9
Oil Filter Cap 1 30 1.5
Exhaust Cylinder Bolt 2 6 0.9 Stud Bolt
Muffler Flange Fixed Bolt 2 6 1.2
Muffler Bracket Fixed Bolt 2 8 3.5
Cam Shaft Holder Face Nut 4 8 2.0
Valve Adjuster Fixed Nut 2 5 0.9
Gear Oil Releasing Bolt 2 8 1.3
Clutch Cover Fixed Nut 1 12 5.5
Drive Face Ass’y Fixed Nut 1 12 5.5
Pri. Fixed Sheave Fixed Nut 1 12 5.5
ACG Fly Wheel Fixed Nut 1 12 5.5
Spark Plug 1 10 1.2
Starter Clutch Lock Nut 1 22 9.5 Counter Clock type

1-5
INFORMATION FOR PREPARATION
The following drawing that shows the disassembling situation of the cover parts
for GK-125R Go-Gart.

1-6
engine speed go up engine speed can't
go up fully
ignite timing is
correct ignite timing isn't correct
valve gap is correct valve gap
isn't correct
compression pressure
is normal
compression
pressure
is too low
no blocking blocking
spark plug normal spark plug stain
oil quantity
is normal oil quantity is too rich
normal abnormal
normal over heat
no knocking knocking
INFORMATION FOR PREPARATION
REVOLUTION NOT SMOOTH , LOST POWER
Diagnose
start engine and
go up speed slight
adjusting ignite
timing
adjusting valve gap
is not correct
testing compression
pressure
check carburetor
blocking ?
loosen spark plug
and check
check the oil
quantiity of
crankcase is too
rich or dirty?
check cylinder head
lubricating ?
engine over heat
increase engine
speed or continue
turning at high
speed
Check and Adjust
air cleaner blocking
fuel supply isn't smooth
air hole of air tank blocking
exhaust pipe blocking
auto.plunger starter damage
film of carburetor damage
fuel cup damage
C.D.I damage
pulser coil damage
valve gap adjusting isn't correct
valve set over abrade
valve set damage
cylinder, piston abrade
cylinder gasket leakage
valve timing isn't correct
cleaning carburetor
cleaning the stain
spark plug type isn't correct
oil flowing is too rich
oil flowing is too lean
oil doesn't circulate
oil tubing blocking
oil supply is too lean
cylinder, piston abrade
mixutre gases is too lean
carbon residue in combustion chamber
is too more
igniting time is too earily
fuel isn't good
clutch sliding
mixutre gases is too lean
carbon residue in combustion chamber
is too more
igniting time is too earily
fuel isn't good
Reason of Trouble
continue

1-7
normal abnormal
INFORMATION FOR PREPARATION
REVOLUTION NOT STABLE (LOW R.P.M.)
Diagnose Check and Adjust
adjusting is correct adjusting isn't
correct
no sucking air sucking air
sparking normal sparking abnormal
normal abnormal
ignition timing adjusting
adjust the carburetor fuel
adjuste screw
carburetor sucking air
loosen spark plug,
connecct with spark cap
and contract with frame,
check the spark plug
sparking ?
check A.C.G
end
Reason of Trouble
C.D.I damage
pulser coil damage
mixture gases too lean
(loosing screw)
mixture gases too rich
(locking screw)
spark damage or stain
C.D.I damage
A.C.G damage
coil damage
spark plug cable damage odr short
main switch damage
A.C.G damage
air hole damage or blocking
(-) pressure tube damage
gasket damage
the screw of carburetor is
loosen
(-) pressure tube broken

1-8
normal abnormal
INFORMATION FOR PREPARATION
REVOLUTION NOT SMOOTH(HIGH SPEED)
Diagnose
Check and Adjust
normal abnormal
normal abnormal
no blocking blocking
valve timing is
correct valve timing isn't correct
adjusting ignite timeing
adjusting valve gap
check fuel cup supply
normal ?
carburetor blocking
check and adjust valve
timing
Reason of Trouble
C.D.I damage
ACG pulse coil damage
fule filter blocking
air hole of fuel tank blocking
fuel cup damage
fuel of tank is too less
camshaft gear mark position is not
correct
normal spring broken or
elastic deformation
end
check the spring of valve
adjusting isn't correct
valve set damage
cleaning
spring damage

1-9
voltage of battery
can't go up voltage of battery
is normal
INFORMATION FOR PREPARATION
CHARGE ABNORMAL
Diagnose Check and Adjust
normal measure value
too high
battery have voltage battery have not
voltage
normal abnormal
start engine and measure
voltage of the two
terminal for battery
measure the resistance of
ACG coil
check the regulator
check socket of regulator
loosen ?
Reason of Trouble
battery damage
coil damage
terminal damage
YL wire damage
R wire damage
regulator damage
socket damage
ACG damage
(over charge)
main switch at ON
the battery have
voltage
main switch at ON
the battery have no
voltage
normal socket loosen
GR wire broken
regulator damage
socket damage
check the socket of
regulator
check the voltage between
regulator and frame

1-10
no sparking or weak sparking strong
INFORMATION FOR PREPARATION
SPARK PLUG NO SPARKING
Diagnose Check and Adjust
loosen no loosen
normal abnormal
normal abnormal
normal abnormal
change spark plug and
check again
check spark plug, cap,
ignition coil loosen?
check C.D.I unit socket
loosen ?
check the terminal of
C.D.I unit unimpeded?
measure resistance
check relate spare parts
Reason of Trouble
the previous spark plug damage
spark plug cap loosen
main switch damage
pulser coil damage
coil damage
lighten coil damage
the previous C.D.I unit damage
socket damage
normal abnormal
main switch damage
socket, joint connect abnormal
change CDI unit
abnormal
change ignition coil
the previous coil damage

2-1
CHECK AND ADJUST
INFORMATION
WARNNING
＊ Do not start the engine at a close zone, because the exhaust gases from the
engine including some noxious emission such as CO, HC, NOx... etc. that can
result serious damage for ealth.
＊ Strictly prohibit using any flammable thing in the working zone, because that
can rise fire easily.
ENGINE：
ITEM SPECIFICATION REMARK
Throttle Free Play 2~6 mm
Spark Plug Gap 0.6~0.7 mm
C7HSA without resistance
Spark Plug Type CR7HSA with resistance
0.06mm intake valve
Valve Gap 0.10mm exhaust valve
Idle Speed 1700±100 rpm
0.9 L resolve the engine
Engine Oil Capability 0.75 L only change engine oil
350 cc resolve the gear
Gear Oil 300 cc only change gear oil
Compression Pressure 12.8kg/cm2570 RPM
Ignite Timing 13°BTDC ±2°1700±100 rpm
CHASSIS：
ITEM SPECIFICATION REMARK
Parking Brake Free Play 10~20 mm
Front Tire Pressure 1.68 kg/cm2（24psi）
Rear Tire Pressure 1.68 kg/cm2（24psi）
Torque of Front Tire Nut 3.5 kg-m
Torque of Rear Tire Nut 11.0 kg-m

2-2
CHECK AND ADJUST
MAINTENANCE SCHEDULE
Please follow the maintenance schedule to do the routine maintenance.
I: Inspection and clean, lubricate, correct, replace if necessary.
A: Adjust. R: Replace. C: Clean
Regular Service Mileage (km)
1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000
Engine oil R R R R R R R R R R R R
Oil filter C C C
Fuel filter R R
Gearoil R R
Valve gap A A A A A A
Carburetor I I C
Air cleaner I R R
Spark plug Clean the plug for each 3000 km, replace it if necessary.
Brake system I I I I I I I I I I I I
Belt I
Suspension I I I
Nuts,bolts I
Tire I I I
Steering I I I
Note：
(1) If the vehicle is new then the motor and gear oil have to replace at the first
300 km.
(2) For safety reason, we suggest the maintenance should be done at local
service center.
(3) If the driving condition is very abominable such as rainy, dust zone or
heavy load... that we suggest operating maintenance more frequency.

2-3
CHECK AND ADJUST
FUEL FILTER
•The filter is located underneath the
carburetor.
•Check the fuel pipe. If the tube has
any damage then change it.
WARNNING
＊Smoking prohibited
THROTTLE LEVER PLAY
•Check the throttle lever operating
whether is smoothly.
•Check the throttle lever play
whether is normal.
The main adjusting nut for throttle play
is on the side of carburetor.
•Loose the fixed nut and adjust the
play nut to proper position.
The micro-adjusting nut for the throttle
play is under the throttle grip.
•Removing the prevention dust cover
of throttle cable, loose the fixed nut
and adjust the play nut to proper
position.
fuel filter
fuel cup
Play nut
Fixed nut

2-4
CHECK AND ADJUST
AIR CLEANER
•Take-off the tapping screws of air
cleaner cover and remove the cover.
•Take-off two screws of air filter.
•Check the filter whether is dirty or
damaged. If it‘s dirty or damaged then
clean it or change a new one.
＊ The material of filter is paper with
sponge, thus don‘t use compression
air to clean the filter.
Check period：
If the vehicle often driving at the rainy or
abominable surroundings, please check
the filter more frequently.
SPARK PLUG
•Remove the spark plug cap.
•If the spark plug grimy or with carbon
residue then using the copper brush to
clean it.
Spark plug specification
C7HSA：without resistance
CR7HSA：with resistance
Check the gap of spark plug
Gap：0.6~0.7 mm
•Using the standard plug socket spanner
to install the spark plug.
screw
air cleaner cover
air filter
screw

2-5
CHECK AND ADJUST
VALVE ADJUSTING
＊ When you check or adjust the valve,
do it at the low engine temperature
(about 35°C)
•Remove cylinder head cover.
•Rotate the cooling fan and keep the
gear mark of camshaft aim at the TDC
position and the ACG flywheel “T”
mark aim at the mark of crankcase.
＊ When you adjusting the valve, don’t
invert the crankshaft, otherwise can
not adjust the exhaust valve.
VALVE GAP CHECK & ADJUST
Valve gap：IN. ：0.06 mm
EX.：0.10 mm
•Loose the fixed nut and rotating the
adjusting nut reach to the proper gap.
•Screw the fixing nut and check the
gap again.
•Using the valve gap adjuster to adjust
the valve gap.
ADJUSTING IDLE SPEED
＊ Engine idle speed adjustment have
to do it when the engine is warm.
•Starting the engine and connect with
the rpm meter.
•Adjust the idle speed adjust screw
reach to the normal idle speed.
The idle speed is 1700±100 rpm.
If the idle speed is unstable or slightly
pull the throttle the engine does not go
smoothly then adjust the throttle valve
stopper screw.
valve screw adjust tool
throttle stopper screw