Brixton BX125 User manual

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Model BX125 Motorcycle
Service Manual
ROHENTWURF/ DRAFT
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Contents
Preface ............................................................................ 3
Service Data ........................................................................ 4
Inspection/Adjustment ............................................................... 17
Vehicle body Inspection and Maintenance.................................................... 32
I Braking System ....................................................................... 33
1.1 Maintenance Instructions .......................................................... 33
1.2 Fault Diagnosis.................................................................. 34
1.3 Front Hydraulic Brake ............................................................ 35
1.4 Rear Hydraulic Brake............................................................. 37
II Motorcycle Exteriors .................................................................. 39
III Front wheel/ front suspension ........................................................... 41
3.1 Service Data .................................................................... 41
3.2 Fault Diagnosis.................................................................. 42
3.3 Front wheel..................................................................... 43
3.4 Steering handlebar .......................................................... 45
3.5 Front fork ...................................................................... 46
IV Rear Wheel/Rear Suspension ........................................................... 50
4.1 Service Data .................................................................... 50
4.2 Fault Diagnosis.................................................................. 51
4.3 Rear Wheel..................................................................... 52
4.4 Rear Shock Absorber ............................................................. 52
4.5 Rear swing arm................................................................ 53
4.6 Drive Chain .................................................................... 54
V. Battery/Charging System ............................................................... 58
5.1 Service Data .................................................................... 58
5.2 Fault Diagnosis.................................................................. 59
5.4 Charging System ................................................................ 61
5.5 Voltage-current Regulator ......................................................... 62
5.6 Generator Charging and Lighting Coils ............................................... 63
5.8 Generator Removal .............................................................. 64
VI Ignition System .................................................................. 65
6.1 Service Data .................................................................... 65
6.2 Fault Diagnosis.................................................................. 66
6.3 Ignition System Inspection......................................................... 67
6.4 Ignition Coil .................................................................... 69
6.5 Trigger ........................................................................ 70
VII. Starting System................................................................. 70
7.1 Service Data .................................................................... 70
7.2 Fault Diagnosis.................................................................. 71
7.3 Starter Motor ................................................................... 71
7.4 Starter Relay.................................................................... 73
VIII. Bulbs/Switches/Instruments .......................................................... 75
8.1 Service Data .................................................................... 75
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8.2 Fault Diagnosis.................................................................. 75
8.3 Headlamp bulb replacement........................................................ 76
8.4 Replacement of the front .......................................................... 76
turn signal light..................................................................... 76
8.5 Replacement of taillight/license plate light/rear turn signal light............................ 76
8.6 Instrument...................................................................... 77
8.7 Main Switch .................................................................... 77
8.8 Electric Horn ................................................................... 78
8.9 Handle Switch .................................................................. 78
Inspection and Maintenance of Engine ...................................................... 79
IX Lubricating system ............................................................... - 81 -
9.1 Service Data ................................................................ - 81 -
9.2 Fault Diagnosis.............................................................. - 82 -
9.3 Engine Oil Pump ............................................................ - 83 -
Cylinder head ...................................................................... - 84 -
10.1 Service Data ............................................................... - 85 -
10.2 Fault Diagnosis............................................................. - 86 -
10.3 Cylinder Head ............................................................. - 86 -
XI Cylinder Block and Piston ......................................................... - 95 -
11.1 Service Data ............................................................... - 95 -
12.2 Fault Diagnosis............................................................. - 96 -
12.3 Cylinder Block ............................................................. - 96 -
XII Crankcase..................................................................... - 101 -
12.1 Service Data .............................................................. - 101 -
12.2 Fault Diagnosis............................................................ - 102 -
12.3 Crankcase ................................................................ - 103 -
12.4 Clutch ................................................................... - 104 -
12.5 Gearshift Mechanism ....................................................... - 110 -
13.6 Crankshaft Connecting Rod Assembly.......................................... - 111 -
13.7 Transmission chamber ...................................................... - 114 -
Exhaust System Inspection and Maintenance ............................................ - 117 -
XIII Exhaust control system.......................................................... - 117 -
13.1 Exhaust control system Guarantee ............................................. - 117 -
13.2 Periodical Maintenance Instructions ........................................... - 118 -
13.3 Mechanical Functions of Exhaust Control System................................. - 119 -
13.4 Catalytic Conversion System ................................................. - 120 -
Inspection and Maintenance of Electronic Fuel Injection System ............................. - 123 -
XIV. Electronic Fuel Injection System.................................................. - 125 -
14.1 Introduction to Electronic Fuel Injection System.............................. - 125 -
14.2 Parts of Electronic Fuel Injection System ....................................... - 125 -
14.3 Fault diagnosis method...................................................... - 134 -
14.4 Common Trouble Shooting Methods ........................................... - 141 -
14.4.3 Simple troubleshooting methods............................................. - 142 -
BX125 Circuit Diagram ............................................................. - 147 -
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Preface
The service manual contains descriptions of maintenance essentials on
BX125 motorcycle.
Service data include attentions that shall be paid on all the maintenance
operations in the service manual. Please read the manual carefully before
operation.
Check and adjustment contains statements on the main points of
inspection and adjustment, safety of the vehicle, maintenance means of
each component’s performance. This shall be implemented from the time
of periodical inspection.
The parts after Part 1 demonstrate disassembly, assembly and main points
of inspection of engine, finished motorcycle, engine and other
components.
System diagrams, disassembly drawings, maintenance, fault diagnosis
and explanations are presented before each part when compiled.
Notes:
If patterns or structures of the motorcycles change, or differences exist
between pictures, drawings, instructions or others and physical products,
please take the later as the standard. The product is subject to change
without further notice.
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Service Data
General Safety Maintenance Regulation
Specification Sheet Fault Diagnosis
General Safety
Carbon monoxide (CO)
When it is necessary to start the engine, please make sure the workplace is well ventilated. You
shall never run the engine in an enclosed place.
Attentions
Gas exhausted from the motorcycle contains toxic carbon monoxide, which may lead to loss of consciousness
and even death.
It is necessary to run the engine in an open area. If the engine is run in an enclosed site, ventilation
system shall be used.
Gasoline
Work in well-ventilated site. Fire and smoking are strictly forbidden in working sites or gasoline
storage places.
Battery
Battery electrolyte contains sulfuric acid, so do not let the eyes, skin, clothes infected with
electrolyte. Once the skin, clothes infected with electrolyte, thoroughly rinse with water; if
infected eyes, you should immediately go to hospital.
Special Tools
Correctly select the common tools and special tools when assembling or disassembling parts, and
the special tools shall not be alternated by common tools. In addition, the force should be
appropriate to avoid damaging parts.
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High-temperature Burn
Pay attention to your safety during maintenance. Carefully, do not be burnt by the ghi-temperature
engine, exhaust pipe, muffler and other hot parts. You should take care of each other in case of
cooperation with others.
Maintenance Regulations
While repairing and servicing, try to use tools of metric system as possible as you can. Incorrect
tools may damage the motorcycle.
Before take down or open protecting plate for maintenance work, please clean the dirt on external
surface of the component or the assembly to prevent the dirt from falling into the engine, chassis
or braking system.
After disassembly and before measuring friction, please clean
the components and purge with air compressor.
Do not bend or distort during operation to avoid difficult
operation or earlier damage.
Plastic parts may deteriorate due to aging, which are apt to be damaged by solvent or oil. Check
before re-installation and replace if necessary.
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While removing a component with many assemblies, do from
outside to inside. Loosen firstly smaller assemblies.
For the complicated assemblies, such as gearbox, keep them in
a proper assembling order for the sake of easy assembly later.
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 assemblies and protecting
plates. They shall be installed at correct positions. If confused, just put
the bolt inside 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 it is
possible to be damaged when installed.
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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
dustproof boot back to its originally designed position.
Disassembly of ball bearing: use a tool to push against one or
two (inner and external) bearing races. If the force works only
on one bearing race (whatever inner or external), the bearing
may be damaged when disassembled and it must be replaced.
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Specifications (BX125)
Model
BX125
Engine
Engine type
157FMI-C
Overall Length(mm)
2020
Fuel
93# unleaded gasoline
Overall Width(mm)
910
Number of
cylinders
1
Overall height(mm)
1105
Bore*stroke
57.3 mm *48.4 mm
Wheelbase(mm)
1320
Total
Displacement
124.8
Weight (kg)
Front
shaft
58kg
Starting mode
Electric
Rear
shaft
76kg
Cooling mode
Air cooling
Total
134kg
Lubricating
mode
Combined force splash
Tire
Spec.
Cover tire of the front wheel
100/90-18
Air cleaner
Paper - element
Cover tire of the rear wheel
120/80-17
Drive Train
Clutch type
Wet multi-plate
friction type
Fuel tank
capacity
14L
Gearshift
pattern
Manual
Performance
Max. speed
101 km/h
Climbing
capacity
Maximum climbing
angle should not be less
than 20 degrees
Transmission
Chain drive
Idle speed-rpm
1500± 100rpm/min
Electricals
Battery
capacity/type
12V-10AH/
lead-acid type
Max. torque
11.4N.m/7000r/min
Max. power
8.3KW/ 8500 r/min
Generator type
permanent magnet
AC motor
Compression
ratio
9.3:1
Spark plug
D8RTC
Spark plug
stroke
0.6-0.8mm
Brake
Diameter of
front brake
disc
φ276mm
Ignition type
ECU
Diameter of
rear brake disc
φ220mm
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BX125
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