If the spark plug center electrode [A] and/or side electrode [B] are corroded or damaged, or if the insulator [C] is cracked, replace the plug.
If the spark plug is dirtied or the carbon is accumulated, replace the spark plug.
If the gap is incorrect, replace the spark plug.
Spark Plug Gap: 0.8
0.9 mm (0.031
0.035 in.)

Standard Spark Plug Type: NGK CR9EIA-9
Stick Coil Primary Peak Voltage Inspection
Interlock Operation InspectionTroubleshooting guide
Engine Does Not Start
Starter Motor Won’t Turn
Engine stop switch off
Transmission not in neutral
Fuse blown
Battery leads do not make good electrical
contact with battery terminals
Battery discharged
Engine Cranks, But Won’t Start
No fuel in tank
Fuel line clogged
Fuel ...
Cylinder (Upper Crankcase) Wear Inspection
Split the crankcase (see Crankcase Splitting).
Remove the pistons (see Piston Removal).
Assemble the cylinder (upper crankcase) [A], the cylinder
head [B] and the cylinder head gasket [C].
Tighten the cylinder head bolts (see Cylinder Head Installation
in the Engine Top End chapter).
...
Starter Motor Assembly
Install the positive brush assy [A] and the starter motor
terminal [B] as shown in the figure.
Replace the O-ring [C] with a new one, and install it.
Install:
Brush Springs [A]
Negative Brush Assy [B]
Turn the stopper side [C] to inside.
Tighten:
Torque - Brush Holder S ...