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 brake fluid level
Front brake
Front brake
Minimum level mark
Rear brake
Rear brake
Minimum level mark
Insufficient brake fluid may allow air to
enter the brake system, possibly causing
it to become ineffective.
Before riding, check that the brake fluid
is above the minimum level mark an ...
Faulty lighting or signaling system
Headlight does not come on
- Wrong headlight bulb
- Too many electrical accessories
- Hard charging
- Incorrect connection
- Improperly grounded circuit
- Poor contacts (main or light switch)
- Burnt-out headlight bulb
Headlight bulb burnt out
- Wrong headlight bulb
- Faulty battery
- Fau ...
Installing the front wheel (disc)
1. Install:
Front brake disc
NOTE:
Be sure to install the front brake disc with the
arrow mark "a" on the disc facing out.
Tighten the brake disc bolts in stages and in a
crisscross pattern.
2. Check:
Front brake disc
Refer to "CHECKING THE FRONT BRAKE
DISC" on page 4 ...