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:
Checking the front brake disc
1. Remove:
Front wheel
Refer to "FRONT WHEEL" on page 4-6.
2. Check:
Brake disc
Damage/galling Replace.
3. Measure:
Brake disc deflection
Out of specification Correct the
brake disc
deflection or replace the brake disc.
a. Place the vehicle on a suitable stand ...
Adjusting the engine idling speed
The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.
Remove panel A.
Check the engine idling speed
and, if necessary, ...
Engine tightening torques
Cylinder head tightening sequence:
Generator cover tightening sequence:
Clutch cover tightening sequence:
Crankcase tightening sequence:
A. Left crankcase
B. Right crankcase ...