Use the micrometer to measure at several points around the ring.
Piston Ring Thickness Standard:
Top [A] 0.77
0.79 mm (0.0303
0.0311 in.)
Second [B] 0.78
0.79 mm
(0.0307
0.0311 in.)
Service Limit:
Top 0.70 mm (0.0276 in.)
Second 0.71 mm (0.0280 in.)

If any of the measurements is less than the service limit on either of the rings, replace all the rings.
NOTE
When using new rings in a used piston, check for uneven groove wear. The rings should fit perfectly parallel to the groove sides. If not, replace the piston.
Piston Ring Groove Width Inspection
Piston Ring End Gap InspectionSpark Plugs
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 ...
Clutch Cover Removal
Remove:
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Clutch Cable Lower End (see Cable Removal)
Clutch Cover Bolts [A]
Turn the release lever [A] counterclockwise as shown,
and remove the clutch cover.
About 90В° [B]
...
Main Throttle Sensor Output Voltage Inspection
Measure the output voltage at the main throttle sensor in
the same way as input voltage inspection, note the following.
Disconnect the main throttle sensor connector and connect
the setting adapter [A] between these connectors.
Special Tool - Throttle Sensor Setting Adapter: 57001
-15 ...