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:
Multi-function display
Multi-function display
Multi-function display
"RESET/SELECT" button
WARNING
Be sure to stop the vehicle before
making any setting changes to the
multi-function display. Changing
settings while riding can distract the
operator and increase the risk of an
accident.
The multi- ...
Faulty clutch
Clutch slips
1. Clutch
Improperly assembled clutch
Improperly adjusted clutch cable
Loose or fatigued clutch spring
Worn friction plate
Worn clutch plate
2. Engine oil
Incorrect oil level
Incorrect oil viscosity (low)
Deteriorated oil
Clutch drags
1. Clutch
Unevenly t ...
Installing the shift forks and shift drum assembly
1. Install:
Shift fork-L "1"
Shift fork-C "2"
Shift fork-R "3"
Shift drum assembly "4"
Springs
Shift fork guide bar "5"
NOTE:
The embossed marks on the shift forks should
face towards the right side of the engine and be
in the following sequence: "R", "C", "L".
2. Check:
Tr ...