Brixton BX125 User manual

0
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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Fault Diagnosis
Hard to Start or Unable to Be Started
Fault Diagnosis Adjustment Fault Cause
Adequate and smooth
gasoline supplied for
the injector
No gasoline
supplied for
the injector
Check whether
the gasoline
pump works
normally
Sparking of
spark plug
Weak sparks of
spark plug, no
sparks of spark plug
Remove the spark plug,
put the spark plug into
spark plug cover, and
check whether there are
sparks of spark plug after
bonding with the engine
Compression
pressure is
normal
Too low or no
compression
pressure
Determination of
compression pressure
No ignition
outbreak of
engine
Ignition outbreak
of engine but
without starting
Wet spark
plug
Dry spark
plug
Remove the spark plug
for inspection again
No gasoline in the gasoline tank
Oil tube blockage of gasoline tank injector
Oil tube blockage of gasoline pump
Tube blockage of fuel tank evaporation
control system
Blockage of gas filter
Insufficient pressure of gasoline pump
Failure of spark plug
Polluted spark plug
Failure of ECU Assembly
Failure of trigger
Ignition coil wire is disconnected or under
short-circuits
Ignition coil is disconnected or under
short-circuit.
Failure of main switch
Failure of charge coil
Failure of startup clutch
Failure of cylinder piston and piston ring
Air leakage of cylinder gasket
Failure of automatic choke apparatus
Air in theinjection manifold
Improper ignition time
Improper adjustment of throttle
adjustment screw
Excessive gasoline injected by injector
Failure of automatic choke apparatus
Large throttle opening
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Inflexible rotation (low revolutions or powerless)
Fault Diagnosis Adjustment Fault Cause
Engine rpm
rises
Engine rpm
cannot rise
completely
Slowly start the
engine
Proper ignition
time
Improper ignition
time
Adjust ignition
timing and adopt
ignition timing light
Compression
pressure is
normal
Compression
pressure is
too low
Determination of
compression
pressure
No blockage
Blocked
Polluted and
discolored
No pollution
and discoloring
Remove the spark
plug for inspection
Throttle blockage
inspection
Normal
Abnormal
No overheat
Overheat
No knocking
Knocking
Accelerate to travel
or operate
Engine overheat
Check the lubrication of
machine oil in cylinder head
Machine oil is
normal
Excessive
machine oil
Check whether the machine
oil in crankshaft tank is
excessive or polluted
Blockage of air filter
Failure of gasoline
Tube blockage of fuel tank
evaporation control system
Blockage of exhaust pipe
Failure of automatic choke
apparatus
Failure of throttle
Failure of ECU Assembly
Failure of trigger
Failure of cylinder piston and
piston ring
Air leakage of cylinder gasket
Remove dirts
Remove dirts
Thermal value of spark plug is
sub-standard.
Excessive machine oil
Insufficient machine oil
No replacement of machine oil
Piston cylinder is worn.
Gaseous mixture is too thin.
Failure of gasoline
Too much carbon deposits in
combustion chamber
Ignition time is too early
Too much carbon deposits in
combustion chamber
Failure of gasoline
Clutch slippage
Gaseous mixture is thin.
Ignition time is too early
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Inflexible rotation (especially low-speed)
Fault Diagnosis Adjustment Fault Cause
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Inflexible rotation (high-speed)
Normal
Abnormal
Ignition time
adjustment
Proper
adjustment
Improper
adjustment
Adjustment of
throttle adjustment
screw
No air
aspirated
Air aspirated
Remove the spark plug, put the
spark plug into spark plug cover, and
start the engine to check whether
there are sparks of spark plug after
bonding with the engine
Proper
sparking of
spark plug
Improper
sparking of spark
plug
Improper
Proper
Air aspirated in
gasket
Failure of ECU Assembly
Failure of trigger
Gasoline mixture is too thin
(release screw)
Gasoline mixture is too thick (lock
screw)
Failure of insulation pad
Fixed nut of throttle is loosen
Insulation pad is broken.
Negative pressure tube is broken
Spark plug is failure of or polluted
Failure of ECU Assembly
Failure of ignition coil
Ignition coil wire is disconnected
or under short-circuits.
Failure of main switch
Negative pressure tube is damaged
Air hole is blocked
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Fault Diagnosis Adjustment Fault Cause
Normal
Abnormal
Ignition time
adjustment
Normal
Abnormal
No
blockage
Blockage
Fatigue elastic
force due to
breaking of spring
Good
Injector clogged
Failure of ECU Assembly
Failure of trigger
Small quantities of gasoline in the
gasoline tank
Gasoline tube gasoline filter
blockage
Tube blockage of fuel tank
evaporation control system
Failure of automatic oil ring
Remove
Failure of spring
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Failure of charging (battery overdischarge or overcharge)
Fault Diagnosis Adjustment Fault Cause
No voltage rise
of battery
The battery voltage rises
to normal, and then
restores to the original
voltage after flameout
Measuring the voltage at
both ends of the battery
and starting the motor
Normal
Abnormal
Check the voltage regulator
plug is loose
Voltage
found
No voltage
found
Alternator coil impedance
measuring
Normal
Abnormal
The voltage
is normal
The voltage is
higher than the
normal
Starting the engine, connecting the red
line of the voltage regulator socket to
avometer positive and negative pole lines
and connecting it to the vehicle body
Check the voltage between the pole lines
and the vehicle body when connecting the
red line of the voltage regulator socket to
multimeter positive and negative pole lines
and connecting it to the vehicle body
Failure of charging
and overcharge
Normal
Poor contact
Check whether the wiring of the voltage
regulator is properly contacted
Test impedance of single
voltage regulator
Out of battery life
Failure of battery
Poor contact of plug
Red line breakage of wiring
Voltage regulator
White line breakage of wiring
Failure of ignition coil
Poor contact of joint
Breakage of AC generator white line
Failure of battery
Poor contact of joint and poor
grounding of wiring
Failure of voltage regulator
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No sparking of spark plug
Fault Diagnosis Adjustment Fault Cause
No or weak
sparking of
spark plug
Strong
sparking
Replace the spark plug
and reinspect
Not loose
Loose
Inspect the spark
plug and reinspect
Normal
Abnormal
Check the conduction between
terminals of ECU assembly wire plug,
and measure the resistance value
Normal
Abnormal
Abnormal
Normal
Related position
inspection
Check whether the ECU
assembly plug is loose
Normal
Abnormal
Abnormal
Use ECU tester to check the
ignition coil
Use ECU tester to check the
ECU assembly
Failure of original spark plug
Spark plug
Poor contact of plug
Failure of main switch
Failure of charge coil
Failure of trigger
Failure of ignition coil
Breakage of main wiring
Poor contact of joint and socket
Failure of CDI Assembly
Failure of ignition coil
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Inspection/Adjustment
Service data Front/rear brake stroke
Periodic maintenance schedule chart Wearing of front/rear brake shoe
Engine oil/ oil screen Headlamp
Fuel filter clutch
Inspection/adjustment of throttle cable Front/rear suspension
system
Air cleaner Bolt/nut/fasteners
Spark plug Wheel rim/tire
Battery Tire specification
Trottle Steering stem bearing and handlebar fixation
Cylinder pressure
Drive chain
Basic Data
General Precautions
！Warning!
Before running the engine, please make sure if the workplace 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 even death.
Under certain conditions, gasoline is highly volatile. Work in well-ventilated site. Fire and smoking are strictly
forbidden in working sites or gasoline storage places.
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18
Frame
Stroke of front brake
handle
10-20mm
Stroke of rear brake
pedal
10-20mm
Pneumatic pressure unit
of tire: Kpa
BX125
Front
wheel
spec.
100/90-18
Front wheel
pneumatic
pressure
225kpa
Rear
wheel
spec.
120/80-17
Rear wheel
pneumatic
pressure
225kpa
Torque
Front wheel
shaft nut
75-85 N·m
Rear wheel shaft nut
75-85 N·m
Periodic maintenance schedule form
Mileage and
interval
Items
300
KM
1000
KM
4000
KM
8000
KM
12000
KM
16000
KM
Tools
New
Vehicle
One
month
three
months
Six
months
Twelve
months
Fifteen
months
*
Air cleaner
I
C
C
R
C
Common tool
*
Gasoline filter
I
C
C
R
C
Common tool
*
Engine oil filter
C
C
C
C
C
C
Common tool
Engine oil replacement
R
Every 5000KM: R
Common tool
Tire pressure
I
I
I
I
I
I
Tire gauge, air
inflator
Battery inspection
I
I
I
I
I
I
Densimeter,
multimeter
Actuating stroke
inspection
I
I
I
I
I
I
Common tool
Inspection of steering
handle bar looseness
I
I
I
I
Common tool
Shock absorber
actuating inspection
I
I
I
I
Common tool
Inspection of looseness
of bolts at all positions
I
I
I
I
I
I
Torque wrench
Check leakage of
gearbox
I
I
I
I
I
I
Common tool
*
Spark plug inspection
and replacement
I
I
R
I
I
Common tool
*
Replacement of
I
Every 5000KM: R
Common tool
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gearbox oil
Lubrication of all the
places on the vehicle
L
L
L
Lubricant
injector
Exhaust pipe
I
I
I
I
I
I
Common tool
*
Ignition timing
I
I
I
I
I
I
Timing light
*
Throttle
A
I
Every 10000km: I
Tachometer,
CO HC
analyzer
*
Idle exhaust gas
inspection
A
I
A
A
A
A
*
Throttle inspection
I
I
I
I
I
Common tool
Fuel hose inspection
I
I
I
I
I
Common tool
Lamps, instrument and
electric apparatus
I
I
I
I
I
I
Visual
multimeter
Main stand and side stand
I
I
I
I
Common tool
Shock absorber
I
I
I
I
Common tool
*
Torque of engine bolt
I
I
I
I
I
Torque wrench
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