Yamaha YZF-R125 Service Manual: Circuit diagram
1. AC magneto
3. Rectifier/regulator
4. Main fuse
9. Battery
Charging system
...
Troubleshooting
The battery is not being charged.
NOTE:
Before troubleshooting, remove the following part(s):
1. Rider seat
2. Left side panel
3. Left lower side cowling
...
Other materials:
Checking the coolant temperature sensor
1. Remove:
Coolant temperature sensor
WARNING
Handle the coolant temperature sensor
with special care.
Never subject the coolant temperature sensor
to strong shocks. If the coolant temperature
sensor is dropped, replace it.
2. Check:
Coolant temper ...
Lubricating the drive chain
The drive chain consists of many interacting
parts. If the drive chain is not maintained properly,
it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehicle is used in dusty areas.
This vehicle has a drive chain with small rubber
O-rings between eac ...
Overheating
Engine
1. Clogged coolant passages
Cylinder head and piston
Heavy carbon buildup
2. Engine oil
Incorrect oil level
Incorrect oil viscosity
Inferior oil quality
Cooling system
1. Coolant
Low coolant level
2. Radiator
Damaged or leaking radiator
Faulty radiator cap
...