Yamaha CS50 - Checking the Spark Plug

CHK
ADJ
CHECKING THE SPARK PLUG
3-10
EAS00060
CHECKING THE SPARK PLUG
1. Disconnect:
• spark plug cap
2. 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.
3. Check:
• spark plug type
Incorrect

Change.
4. Check:
• electrode 
Damage/wear

Replace the spark plug.
• insulator 
Abnormal color

Replace the spark plug.
Normal color is medium-to light tan.
5. Clean:
• spark plug
(with a spark plug cleaner or wire brush)
6. Measure:
• spark plug gap a
(with a wire Thickness gauge)
Out of specification

Regap.
7. Install:
• spark plug
NOTE:
Before installing the spark plug, clean the
spark plug and gasket surface.
8. Connect:
• spark plug cap
Spark plug type (manufacturer)
BR8HS (NGK)
Spark plug type (manufacturer)
0,6 ~ 0,7 mm
20 Nm (2.0 m • kg)