The standard spark plug is shown in the table. The spark plugs should be replaced in accordance with the Periodic Maintenance Chart.
Spark plug removal should be done only by a competent mechanic following the instructions in the Service Manual.
Spark Plug

A. Plug Gap
Coolant Filling
Evaporative Emission Control System (California
model only)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).
...
Exploded View
25. “1T” marked side faces up.
26. “T2” marked side faces up.
27. Hollow mark faces exhaust side.
G: Apply grease.
L: Apply a non-permanent locking agent.
LG: Apply liquid gasket.
M: Apply molybdenum disulfide grease.
MO: Apply molybdenum disulfide oil solution.
...
Special Tools and Sealants
Outside Circlip Pliers:
57001-144
Piston Pin Puller Assembly:
57001-910
Piston Ring Compressor Grip:
57001-1095
Piston Ring Compressor Belt, 67
79:
57001-1097
Bearing Driver Set:
57001-1129
Liquid Gasket, TB1216B:
92104-1064
Liquid Gasket, TB1207B:
92104-2068
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