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:
General chassis
Installing the air filter case
1. Install:
Air filter case joint clamp
NOTE:
Align the projection "a" on the air filter case with
the slot "b" in the air filter case joint clamp.
...
Replacing an auxiliary light bulb
This model is equipped with two auxiliary
lights. If an auxiliary light bulb burns
out, replace it as follows.
Remove the socket (together with
the bulb) by pulling it out.
Auxiliary light bulb
Remove the burnt out bulb by pulling
it out.
Insert a new bulb into t ...
Checking the camshaft sprocket and timing chain guide
1. Check:
Camshaft sprocket
More than 1/4 tooth wear "a" Replace
the
camshaft sprocket, timing chain and crankshaft
as a set.
a. 1/4 tooth
b. Correct
1. Timing chain roller
2. Camshaft sprocket
2. Check:
Timing chain guide (exhaust side)
Damage/wear Replace.
...