If any plate is warped over the service limit, replace it with a new one.

Friction and Steel Plate Warp
Standard: 0.15 mm (0.0059 in.) or less
Service Limit: 0.3 mm (0.012 in.)
Clutch Plate, Wear, Damage Inspection
Clutch Spring Free Length MeasurementCrankshaft Sensor Peak Voltage Inspection
NOTE
Be sure the battery is fully charged.
Using the peak voltage adapter [A] is more reliable way
to determine the condition of the crankshaft sensor than
crankshaft sensor internal resistance measurements.
Disconnect the crankshaft sensor lead connector (see
Crankshaft Sensor ...
Bolts, Nuts and Fasteners Tightness Inspection
Check the tightness of the bolts and nuts listed here. Also,
check to see that each cotter pin is in place and in good
condition.
NOTE
For the engine fasteners, check the tightness of them
when the engine is cold (at room temperature).
If there are loose fasteners, retighten them to ...
Air Switching Valve
Air Switching Valve Operation Test
Refer to the Air Suction System Damage Inspection in the
Periodic Maintenance chapter.
Air Switching Valve Unit Test
Remove the air switching valve (see Air Switching Valve
Removal in the Engine Top End chapter).
Set the hand tester [A] to the × 1 ...