Yamaha YZF-R125 Service Manual: Checking and replacing the rear wheel sprocket
1. Check:
- Rear wheel sprocket
More than 1/4 tooth "a" wear
Replace the rear wheel sprocket.Bent teeth
Replace the rear
wheel sprocket.
b. Correct
1. Drive chain roller
2. Rear wheel sprocket
2. Replace:
- Rear wheel sprocket
a. Remove the self-locking nuts and the rear wheel sprocket.
b. Clean the rear wheel drive hub with a clean cloth, especially the surfaces that contact the sprocket.
c. Install the new rear wheel sprocket.
NOTE:
Tighten the self-locking nuts in stages and in a crisscross pattern.
Assembling the rear wheel
1. Install:
- Wheel bearings
- Oil seals
Refer to "ASSEMBLING THE FRONT WHEEL" on page 4-9.
Checking the rear wheel
1. Check:
Rear wheel axle
Rear wheel
Wheel bearings
Oil seals
Refer to "CHECKING THE FRONT WHEEL"
on page 4-8.
2. Check:
Tire
Rear wheel
Damage/wear → Replace.
Refer ...
Adjusting the rear wheel static balance
NOTE:
After replacing the tire, wheel or both, the rear
wheel static balance should be adjusted.
Adjust the rear wheel static balance with the
brake disc and rear wheel drive hub installed.
...
Other materials:
Starting the engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the sidestand
up.
1. Turn the key to "ON" and make
sure ...
Intake air pressure sensor
1. Check:
Intake air pressure sensor output voltage
Out of specification Replace the throttle
body.
a. Connect the pocket tester (DC 20 V) to the
throttle body sensor assembly coupler as
shown.
Positive tester probe
pink/white "1"
Negative tester probe
gray/black "2"
...
Checking the spark plug
1. Remove:
Right side cover
Refer to "GENERAL CHASSIS" on page 4-1.
2. Disconnect:
Spark plug cap
3. Remove:
Spark plug
CAUTION:Before removing the spark plug, blow away
any dirt accumulated in the spark plug well
with compressed air to prevent it from falling
...