Generic TR 125 User manual

Service Manual
Holtvej 8-10, Høruphav, 6470 Sydals
Telefon: [phone]
Fax: [phone]
E-mail: [email protected] · www.scanmi.dk
CVR: 27 73 31 07
Maj 2013
TR 125

Two-wheel Motorcycle QJ125GY-16A
Instruction and Maintenance Manual
ZHEJIANG QIANJIANG MOTORCYCLE CO., LTD.

Contents
Preface ·································································································· - 1 -
Preparatory Data ······················································································· - 2 -
Inspection/Adjustment ··············································································· - 15 -
Check and Maintenance of Body ··································································· - 32 -
I Braking System ···················································································· - 34 -
1.1 Maintenance Instruction········································································· - 34 -
1.2 Fault diagnosis···················································································· - 35 -
1.3 Front Hydraulic Brake··········································································· - 36 -
1.4 Back liquid brake················································································· - 38 -
II Vehicle Housing ··················································································· - 42 -
III Front Wheel/Front Suspension ······························································· - 45 -
3.1 Preparatory Data ················································································· - 45 -
3.2 Fault diagnosis···················································································· - 45 -
3.3 Front wheel ······················································································· - 47 -
3.4 Direction handle·················································································· - 49 -
3.5 Front fork··························································································- 49 -
IV Rear Wheel/Rear Suspension ································································· - 54 -
4.1 Preparatory Data ················································································· - 54 -
4.2 Fault Diagnosis ··················································································· - 55 -
4.3 Rear wheel ························································································ - 56 -
4.4 Rear Shock Absorber ············································································ - 57 -
4.5 Rear Swing Arm·················································································· - 58 -
4.6 Drive Chain ······················································································· - 59 -
V Storage Battery/Charging System ····························································· - 62 -
5.1 Preparatory Data ················································································· - 62 -
5.2 Fault Diagnosis ··················································································· - 63 -
5.3 Storage Battery ··················································································· - 64 -
5.4 Charging System ················································································· - 65 -
5.5 Voltage-current Regulator······································································· - 66 -
5.6 Alternator Charging Coil ········································································ - 67 -
5.7 alternator light coil ··············································································· - 67 -
5.8 disassembly of alternator········································································ - 68 -
VI Ignition System··················································································· - 71 -
6.1 Preparatory Data ················································································· - 71 -
6.2 Fault Diagnosis ··················································································· - 72 -
6.3 Ignition System Inspection······································································ - 73 -
6.4 CDI Assembly ···················································································· - 75 -
6.5 Ignition Coil ······················································································ - 75 -
6.6 Trigger ····························································································· - 76 -
VII Starting System ················································································· - 78 -
7.1 Preparatory Data ················································································· - 78 -
7.2 Fault Diagnosis ··················································································· - 79 -

7.3 Starting Motor ···················································································· - 79 -
7.4 Starting Relay····················································································· - 81 -
VIII Bulbs/Switches/Instruments································································· - 82 -
8.1 Preparatory Data ················································································· - 82 -
8.2 Fault Diagnosis ··················································································· - 82 -
8.3 Headlamp Bulb Replacement··································································· - 83 -
8.4 Front Turn Signal Lamp Bulb Replacement ·················································· - 84 -
8.5 Taillight/license plate lamp/rear turn-lamp bulb replacement ······························ - 84 -
8.6 Instrument························································································· - 85 -
8.7 Main Switch ······················································································ - 85 -
8.8 Horn································································································ - 86 -
8.9 Handle switch····················································································· - 86 -
Engine Inspection and Maintenance ······························································· - 87 -
IX Lubricating System ············································································· - 89 -
9.1 Preparatory Data ················································································· - 89 -
9.2 Fault Diagnosis ··················································································· - 89 -
9.3 Oil Pump ·························································································· - 90 -
X Cooling system ···················································································· - 93 -
10.1 Preparatory data················································································· - 93 -
10.2 Fault diagnosis ·················································································· - 93 -
10.3 Water pump······················································································ - 94 -
XI Cylinder Head···················································································· - 97 -
11.1 Preparatory Data ················································································ - 97 -
11.2 Fault Diagnosis·················································································· - 98 -
11.3 Cylinder Head ··················································································· - 98 -
XII Cylinder Block and Piston·································································· - 107 -
12.1 Preparatory Data ·············································································· - 107 -
12.2 Fault Diagnosis ··············································································· - 108 -
12.3 Cylinder Head················································································· - 108 -
XIII Crankcase······················································································- 113 -
13.1 Preparatory Data ···············································································- 113 -
13.2 Fault Diagnosis ················································································- 114 -
13.3 Crankcase ·······················································································- 115 -
13.4 Clutch ···························································································- 116 -
13.5 Gearshift mechanism········································································· - 121 -
13.6 Crankcase connecting rod combination···················································· - 122 -
13.7 Variable speed chamber······································································ - 125 -
Exhaust System Inspection and Maintenance·················································· - 128 -
XV Emission Control System ··································································· - 129 -
15.1 Emission Control System Guarantee······················································· - 129 -
15.2 Regular maintenance guidelines ···························································· - 129 -
15.3 Emission Control System Mechanical Functions········································· - 130 -
15.4 Catalyst conversion system·································································· - 131 -
15.5 Solutions to Idle Exhaust Exceeding Specified Value ··································· - 132 -

Inspection and Maintenance of EFI System ···················································· - 133 -
XVI EFI System Description ···································································· - 134 -
16.1 Introduction to EFI System of finished enginecycle ····································· - 134 -
16.2 EFI system parts ·············································································· - 134 -
16.3 Troubleshooting diagnosis··································································· - 146 -
16.4 Common troubleshooting···································································· - 153 -
16.4.3 Concise troubleshooting ··································································· - 154 -
QJ125GY-16A circuit diagram ············································································i

- 1 -
Preface
The Instruction and Maintenance Manual contains an introductory description of
maintenance on QJ125GY-16A motorcycle.
Preparatory data include attentions that shall be paid on all the maintenance
operations in the Instruction and Maintenance Manual. Please read the manual
carefully before operation.
Check and adjustment contains main aspects for inspection and adjustment, safety
of the vehicle, performance and maintenance of each component. This shall be
started from the time of periodical inspection.
The parts following Chapter One demonstrate the main point of disassembly,
installation and check of electrics parts, finished vehicle, engine and other
components.
System diagrams, breakdown drawings, fault diagnosis, maintenance and other
explanatory contents are presented before each part.
Note:
The parts which are not explained separately in the manual apply to both of the
motorcycles.
For any pattern and structure change of the motorcycle, or any difference between
the product and pictures, drawings and instructions in the manual, the product shall
prevail. The product is subject to changes without prior personal notice.

- 2 -
ZHEJIANG QIANJIANG MOTORCYCLE CO., LTD.
Finished Automobile Institute
Preparatory Data
General Safety Maintenance Rules
Specification Table Fault Diagnosis
General Safety
Carbon monoxide (CO)
When it is necessary to start the engine, please make sure the operation area is well ventilated. Never run the
engine in an enclosed place.
Attention
Gas exhausted from the motorcycle contains harmful carbon monoxide, which may lead to loss of
consciousness and death.
It is necessary to run the engine in an open area. To run the engine in an enclosed site, ventilation system shall
be used.
Gasoline
Operate in well-ventilated site. No fire or smoking is allowed in operation site and gasoline storage place.
Storage Battery
Electrolyte in the storage battery has sulfuric acid, so leave eyes、skin and clothes away from it. Once got
electrolyte on our skin or clothes, you will have to wash them by fresh water thoroughly; once into our eyes, to
see a doctor immediately is necessary.
Special Tool

- 3 -
When disassembly and installation is in process, general tools and special tools should be selected correctly.
When it is time to use the special, the general can not be substitution. Besides, appropriate power is welcomed
to avoid the damage of components.
High Temperature Burn
Tips: Do not be burned by engine, exhaust pipe,silencer and other components with high temperature. When
operating together with others, you’d better look after each other and keep a way for safety.

- 4 -
Maintenance Rules
While repairing and servicing, use tools of metric system as possible. Incorrect tools may damage the
motorcycle.
Before taking down or opening protecting plate for repair work, please clean the dirt on the external surfaces
of components or combination parts and prevent the dirt from falling into engine, chassis or braking system
After disassembly and before measuring friction, please clean the
components and blow them with compressed air.
—Bending or Warping are forbidden in operation, otherwise tough
operation or advanced damage will be caused.
Plastic parts may age and deteriorate, which are apt to be damaged
by solvent or oil. Check before re-installation and replace if
necessary.
To loose component with many assembling units, it shall start from
external to internal and loosen smaller assemblies first.
The complicated assemblies such as transmission case shall be put
in proper assembling order for easy assembly in the future.
Incorrect Incorrect
Incorrect

- 5 -
Pay special attention to the key fitting position before disassembly. The components that are not used any more
shall be replaced on time before disassembly.
Length of bolts and screws are different for assembly
components and protecting plates. They shall be installed at correct positions. If confused, just put the bolt in
the hole and see if it matches.
Fill lubricating grease into the groove during oil seal installation. Check
if the oil seal is smooth and if there is any damage to it.
Installation of rubber hose (fuel, vacuum, or coolant):
insert its end into bottom of connector so that there is
enough room for the hose clamp to grip the connector.
Install the rubber or plastic dust cover back to its
originally designed position

- 6 -
Disassembly of ball bearing: use a tool to push against one or
two (internal and external) bearing races. If the force works
only on one bearing race (whatever internal or external), it
may be damaged when the bearing is disassembled, in which
case, it must be replaced

- 7 -
Specifications (QJ125GY-16A)
Model QJ125GY-16A
Engine
Engine type QJ160MI-A
Overall Length (mm) 2030 Fuel type
92# or 95# unleaded
gasoline
Overall Width (mm) 845 Number of cylinders 1
Overall height (mm) 1120 Bore*stroke Ф60 mm *44 mm
Wheelbase (mm) 1385 Displacement 124.4
Vehicle Weight (kg)
Front
axle 63kg Starting mode Electric
Rear
axle 76kg Cooling mode Water cooled
Total 139kg Lubricating mode
Force-feed and splash
lubrication
Wheel Specification
Front (External) Fuel tank capacity 1.2L(Oil change1L)
100/80-17
Rear（External）Air cleaner Filter sponge
130/80-17
Drive Train
Clutch type Wet multi-plate
friction type
Fuel tank capacity 7.5L ± 0.2L
Performance
Top speed 110 km/h
Gear shift pattern Manual 6 gear
Slope climbing force Maximum climbing angle
is not less than 20 degrees
Idle speed 1700± 100rpm/min
Drive Train Clutch type Max. torque 12.18N·m/7500r/min
Electrical
Battery
capacity/type
12V-6AH/YUASA
TT27SL Max. power 11 Kw/ 9000 r/min
Generator type
Alternating current
permanent magnetic
motor
Compression ratio 12.0 : 1
Spark plug NGK CR8E Pressure of cylinder 8.5Mpa
Spark plug
clearance 0.7~0.8mm
Braking
system
Diameter of front
brake disc φ280mm
Ignition type CDI Diameter of rear
brake disc φ240mm

- 8 -
QJ125GY-16A

- 9 -
Fault Diagnosis
Start difficultly or start failed
FaultDiagnosis AdjustmentCheck FaultCause
Oil supplying
for fuel injector
is enough and
smooth
No fuel
supplies to
fuel injector
Check if petrol
pump work well
There is
flashover in
spark plug.
Weak spark or no
spark is in spark
p
lug.
Disassemble spark plug
and put it into spark plug
cover; connect engine to
check whether there is
flashover in spark plug.
Compression
pressure is
normal
Compression
pressure is too
low or none.
Compression
pressure test
No Ignition
outbreak
phenomenon
of engine
With outbreak
phenomenon;
without start
Spark plug is
wet
Spark plug is
dry
Disassemble spark
plug to check again
No fuel in gasoline box
Pipeline block in fuel injector of gasoline box
Block in the pipeline of gasoline pump
Pipeline block in evaporation controlling
system of fuel tank
Block in the gasoline filter
Oil pressure of gasoline pump is not enough.
Unhealthy spark plug
Pollution of spark plug
Unhealthy CDI Group
Unhealthy trigger
Open circuit / short circuit of ignition coil
Open circuit or short circuit in ignition coil
Unhealthy master switch
Unhealthy charge coil
Unhealthy start clutch
Unhealthy cylinder plunger or packing ring
Air leakage of cylinder head gasket
Unhealthy automatic choke
Air in induction manifold
Incorrect ignition time
Bad adjustment of restriction adjustment
screw
Oil injection volume of fuel injector is over
Unhealthy automatic choke
Accelerator opens too much

- 10 -
Rotation unsmooth (No speed or low speed)
FaultDiagnosis AdjustmentCheck FaultCause
Speed of
rotation of
engine arises
Engine speed
can not arise
completely
Start engine and
add oil
Ignition time is
right
Ignition time is
wrong
Adjust ignition correct
time and use ignition
correct time light.
Compression
pressure normal
Compression
pressure too low
Compression pressure
test
No block Block
Pollution / discoloration
No pollution /
discoloration
Disassemble spark plug to check
Carburetor block test
Normal Abnormal
No overheating Overheating
No knockings Knockings
Run or travel in
increased speed
Engine is overheating
Check lubrication of
c
y
linder head oil
Engine oil is
normal
Engine oil is
ove
r
Check whether engine oil volume in
b
ent axle tank is over or
p
ollute
d
Block of air filter
Unhealthy gasoline
Pipeline block in evaporation controlling
system of fuel tank
Block of exhaust pipe
Unhealthy auto-choke
Unhealthy air damper
Unhealthy CDI Group
Unhealthy trigger
Unhealthy cylinder plunger / packing ring
Staleness cylinder cushion
Cleaning pollutions
Cleaning pollutions
Spark plug heat value is not agreeable
Engine oil volume is over
Engine oil volume is less
No change of engine oil
Piston and cylinder wear
Mixed air is too thin
Unhealthy of gasoline
Coal in combustor is over
Ignition time is too early
Coal in combustor is over
Unhealthy of gasoline
Slipping of clutch
Mixed air is too thin
Ignition time is too early

- 11 -
Rotation unsmooth (especially in low speed)
FaultDiagnosis AdjustmentCheck FaultCause
Normal Abnormal
Ignition time
adjustment
Adjust well Adjust not well
Air damper restriction
screw adjustment
No air in Air in
Disassemble spark plug
to check the flashover
Spark plug
flashover
well
Spark plug
flashover not well
Not well
Well
Air into shim
Unhealthy CDI group
Unhealthy trigger
Gas mixture is too thin (loosen bolt)
Gas mixture is too strong (tighten bolt)
Heat filter not well
Loose restrictor fixed nut
Broken shim
Broken negative pressure pipe
Spark plug not well or polluted
CDI not well
Ignition coil not well
Spark plug guide line open circuit or
short circuit
Master switch not well
Negative pressure pipeline damage
Air circulation hole blocked

- 12 -
Rotation unsmooth (especially in high speed)
FaultDiagnosis AdjustmentCheck FaultCause
Normal Abnormal
Ignition time
adjustment
Normal Abnormal
No block Block
Spring breaks with
weak elastic force
Well
Fuel injector block
CDI group not well
Trigger not well
Gasoline is little in gasoline box
Gasoline pipe filter block
Block of fuel tank evaporation
control system pipe
Automatic oil ring not well
Clean
Unhealthy spring

- 13 -
Unhealthy charging (storage battery over discharge or over charge)
FaultDiagnosis AdjustmentCheck FaultCause
Battery voltage
no rise Battery voltage up
to normal; restore
the original voltage
after flameout
Measurement on
both ends of the
battery voltage
started the engine
Normal Abnormal
Check the voltage regulator
plug is loose
Have voltage No voltage
Ac generators coil impedance
values determined
Normal Abnormal
Normal
voltage
Voltage
higher than
normal
Start the engine, the voltage regulator
socket red line connects with electric
meter by three anode and ed body in
electricity
Check voltage regulator by the
multi-purpose socket red line electric
meter of anode and connected body in
Charging bad charging
Normal Loose contact
Check whether the voltage regulator
wirin
g
contact undesirable
The voltage regulator
monomer test im
p
edance
Battery life has come
Unhealthy storage battery
Plug contact undesirable
The red lines open circuit wiring
Voltage adjuster
Wiring white line disconnected
Unhealthy coil
Connector contact undesirable
Wiring white line disconnected
Unhealthy storage battery
Joint contact undesirable wiring
grounding is poor
The voltage regulator is poor

- 14 -
Spark plug without flashover
FaultDiagnosis AdjustmentCheck FaultCause
The spark plug
jump weak or
no fire jump
Hot spark
Replace new spark
p
lu
g
s to chec
k
Without sag With sag
Check the spark
p
lu
g
check a
g
ain
Normal Abnormal
Examination of each terminal wire
plug CDI between conduction,
resistance value measurement
Normal Abnormal
AbnormalNormal
Related parts
inspection
Check whether the plug
CDI
g
rou
p
flabb
y
Normal
Abnormal
Use the test CDI
i
g
nition coil chec
k
Use the check CDI
group CDI test
Abnormal
Spark plug the bad
Spark plug cover relaxation
Plug contact undesirable
The Lord switch bad
Charging coil bad
Trigger bad
Ignition coil badly
The Lord wiring broken
Joint socket contact undesirable
Unhealthy CDI group
Unhealthy ignition coil

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Inspection/Adjustment
Preparatorydata Front/Rearbrakefreestroke
Periodic maintenance schedule Front/Rear brake shoe’s abrasion
Engine oil / Oil-filter screen Headlamp
Gasolinefilter Clutch
Check/Adjustment of accelerator stay wire Front/Rear suspension system
Air cleaner Bolt/Nut/Fastening part
Sparkplug Wheelrim/Tyre
Battery Tyrespecification
Restrictor Steering stem bearing and handle fixation
Cylinder pressure
Driving chain
Preparatory Standard
General
Warning!
• Before running the engine, please make sure the area you are working in is well ventilated. You shall never
run the engine in an enclosed site. Gas exhausted from the motorcycle contains carbon monoxide, which may
lead to loss of consciousness and result in death.
• Under certain conditions, gasoline is highly volatile. Work in well-ventilated site. Fire and smoking are
forbidden in working site or gasoline storage place.