Yamaha YZF-R125 Service Manual: Replacing the headlight bulbs
The following procedure applies to the low beam headlight bulb.
1. Remove:
- Headlight bulb cover "1"
2. Remove:
- Headlight bulb holder "1"
3. Remove:
- Headlight bulb "1"
| WARNING Since the headlight bulb gets extremely hot, keep flammable products and your hands away from the bulb until it has cooled down. |
4. Install:
- Headlight bulb
Secure the new headlight bulb with the headlight bulb holder.
| CAUTION: Avoid touching the glass part of the headlight bulb to keep it free from oil, otherwise the transparency of the glass, the life of the bulb and the luminous flux will be adversely affected. If the headlight bulb gets soiled, thoroughly clean it with a cloth moistened with alcohol or lacquer thinner. |
5. Install:
- Headlight bulb holder
6. Install:
- Headlight bulb cover
The following procedure applies to the high beam headlight bulb.
1. Remove:
- Headlight bulb cover "1"
2. Disconnect:
- Headlight coupler "1"
3. Remove:
- Headlight bulb holder "1"
4. Remove:
- Headlight bulb "1"
| WARNING Since the headlight bulb gets extremely hot, keep flammable products and your hands away from the bulb until it has cooled down. |
5. Install:
Headlight bulb 
Secure the new headlight bulb with the headlight
bulb holder.
| CAUTION: Avoid touching the glass part of the headlight bulb to keep it free from oil, otherwise the transparency of the glass, the life of the bulb and the luminous flux will be adversely affected. If the headlight bulb gets soiled, thoroughly clean it with a cloth moistened with alcohol or lacquer thinner. |
6. Install:
- Headlight bulb holder
7. Connect:
- Headlight coupler
8. Install:
- Headlight bulb cover
Electrical system
Checking and charging the battery
Refer to "ELECTRICAL COMPONENTS" on
page 8-57.
Checking the fuses
Refer to "ELECTRICAL COMPONENTS" on
page 8-57. ...
Adjusting the headlight beams
The following procedure applies to both of the
headlights.
1. Adjust:
Headlight beam (vertically)
a. Turn the adjusting screw "1" in direction "a" or
"b".
A. Left headlight
B. Right he ...
Other materials:
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 ...
Checking the connections
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
Lead
Coupler
Connector
2. Check:
Lead
Coupler
Connector
Moisture → Dry with an air blower.
Rust/stains → Connect and disconnect several
times.
3. Check:
All co ...
Installing the piston and cylinder
1. Install:
Top ring "1"
2nd ring "2"
Oil ring expander "3"
Lower oil ring rail "4"
Upper oil ring rail "5"
NOTE:
Be sure to install the piston rings so that the
manufacturer marks or numbers face up.
2. Install:
Piston "1"
Piston pin "2"
Piston pin clips "3"
NOTE:
...