Yamaha VMX12H Supplementary Service Manual page 120

BRAKE LIGHT SWITCH ADJUSTMENT/
SPARK PLUG INSPECTION
2-37
BRAKE LIGHT SWITCH ADJUSTMENT
1. Adjust:
light operating timing
Hold the main body
your hand so it does not rotate, and
turn the adjuster
timing is correct.
SPARK PLUG INSPECTION
1. Inspect:
Replace.
.Insulator color
Normal condition is a medium to light
tan color.
Distinctly different color
engine condition.
Spark plug
gap
2.
Clean:
plug
Clean the spark plug with a spark plug
cleaner or wire brush.
3.
Inspect:
plug type
Incorrect Replace
Standard Spark Plug:
DPR8EA-9 (NGK)
X24EPR-U9 (N.D.)
4. Measure:
plug gap
Out of specification
Use a wire gauge.
Spark Plug Gap:
0.8 0.9 mm (0.031
5. Tighten:
Plug
NOTE:
Before installing a spark plug, clean the gasket
surface and plug surface.
17.5 Nm (1.75 m-kg, 12.5 ft-lb)
of the switch with
until the operating
Check the
Regap.
-
0.035 in)