Yamaha YZF-R125 Service Manual: 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 into the cylinder. |
4. Check:
Spark plug type
Incorrect →Change.
5. Check:
- Electrode "1" Damage/wear→ Replace the spark plug.
- Insulator "2"
Abnormal color→ Replace the spark plug.
Normal color is medium-to-light tan.
6. Clean:
- Spark plug (with a spark plug cleaner or wire brush)
7. Measure:
- Spark plug gap "a"
(with a wire thickness gauge)
Out of specification → Regap.
8. Install:
- Spark plug
NOTE:
Before installing the spark plug, clean the spark plug and gasket surface.
9. Connect:
- Spark plug cap
10.Install:
- Right side cover Refer to "GENERAL CHASSIS" on page 4-1.
Adjusting the throttle cable free play
NOTE:
Prior to adjusting the throttle cable free play, the
engine idling speed should be adjusted.
1. Check:
Throttle cable free play "a"
Out of specification →Adjust.
2. Remov ...
Checking the ignition timing
NOTE:
Prior to checking the ignition timing, check the
wiring connections of the entire ignition system.
Make sure all connections are tight and free of
corrosion.
1. Remove:
Rider seat
L ...
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 ...
Checking the transmission
1. Measure:
Main axle runout
(with a centering device and dial gauge "1")
Out of specification Replace
the main axle.
2. Measure:
Drive axle runout
(with a centering device and dial gauge "1")
Out of specification Replace
the drive axle.
3. Check:
Transmiss ...
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 to "CHECKING THE TIRES" on page
3-23 and "CHECKING THE WHEELS" on
page 3-25.
3. Measure:
Radi ...