Yamaha YZF-R125 Service Manual: Installing the primary drive gear and balancer gears
1. Install:
- Balancer driven gear "1"
- Lock washer
- Balancer drive gear "2"
- Primary drive gear
- Washer "3"
- Balancer driven gear nut
- Primary drive gear nut
NOTE:
- Align the punch mark "a" in the balancer drive gear "2" with the punch mark "b" in the balancer driven gear "1".
- Be sure to install the washer so that its sharp edge "c" is facing the primary drive gear.
2. Tighten:
- Balancer driven gear nut "1"
- Primary drive gear nut "2"
NOTE:
- Place the aluminum plate "a" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the balancer driven gear nut.
- Place the aluminum plate "b" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the primary drive gear nut.
3. Bend the lock washer tab along a flat side of the nut.
Checking the balancer gears and primary drive gear
1. Check:
Balancer drive gear
Balancer driven gear
Cracks/damage/wear Replace.
2. Check:
Primary drive gear
Refer to "CHECKING THE PRIMARY DRIVE
GEAR" on page 5-43.
...
Crankcase
...
Other materials:
Checking the rectifier/regulator
1. Check:
Rectifier/regulator output voltage
Out of specification → Replace the
rectifier/
regulator.
a. Set the engine tachometer to the spark plug
lead.
b. Connect the pocket tester (DC 20 V) to the
rectifier/regulator coupler as shown.
Positive tester probe
red "1"
Negat ...
Checking the fuel line
1. Remove:
Left side panel
Refer to "GENERAL CHASSIS" on page 4-1.
2. Lift the fuel tank. (Do not disconnect the fuel
hose, drain hose
3. Check:
Fuel hose "1"
Cracks/damage → Replace.
Loose connection Connect properly.
4. Install:
Fuel tank
Refer to "FUEL TANK" on pa ...
Fuel tank cap
Fuel tank cap
Fuel tank cap lock cover
Unlock.
To remove the fuel tank cap
Open the fuel tank cap lock cover.
Insert the key into the lock and turn
it 1/4 turn counterclockwise. The
lock will be released and the fuel
tank cap can be removed.
To install the fuel tank ca ...