Yamaha YZF-R125 Service Manual: Installing the water pump
1. Install:
- Water pump assembly "1"
- O-rings "2"
NOTE:
- Align the projection "a" on the impeller shaft with the slit "b" on the camshaft sprocket bolt.
- Lubricate the O-rings with a thin coat of lithiumsoap- based grease.
2. Fill:
- Cooling system (with the specified amount of the recommended coolant)
Refer to "CHANGING THE COOLANT" on page 3-15.
3. Check:
Cooling system
Leaks 
Repair or replace the faulty
part.
4. Measure:
Radiator cap opening pressure
Below the specified pressure
Replace the
radiator cap.
Refer to "CHECKING THE RADIATOR" on page 6-3.
Assembling the water pump
1. Install:
Water pump seal "1"
(into the water pump housing "2")
CAUTION:Never lubricate the water pump seal
surface
with oil or grease.
NOTE:
Install the water pump ...
Fuel system
...
Other materials:
Introduction
WARNINGDisc brake components rarely require
disassembly.
Therefore, always follow these preventive
measures:
Never disassemble brake components unless
absolutely necessary.
If any connection on the hydraulic brake
system is disconnected, the entire brake
sy ...
Circuit diagram
2. Crankshaft position sensor
4. Main fuse
5. Main switch
6. Radiator fan motor fuse
8. Sidestand switch
9. Battery
17.Engine stop switch
19.Intake air pressure sensor
20.Intake air temperature sensor
21.Throttle position sensor
22.Coolant temperature sensor
23.Lean angle sensor
24.S ...
Troubleshooting
Any of the following fail to light: headlight, high beam indicator light,
taillight, license plate light, auxiliary
light or meter light.
NOTE:
Before troubleshooting, remove the following part(s):
1. Seats
2. Fuel tank
...