If the display function does not work, replace the meter unit.

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Radiator Cap Inspection
Remove:
Radiator Cap (see Coolant Change in the Periodic Maintenance
chapter)
Check the condition of the bottom [A] and top [B] valve
seals and valve spring [C].
If any one of them shows visible damage, replace the cap
with a new one.
Install the cap [A] on a cooling system pr ...
Piston Ring Groove Width Inspection
Measure the piston ring groove width.
Use a vernier caliper at several points around the piston.
Piston Ring Groove Width
Standard:
Top [A] 0.82 0.84 mm (0.0323
0.0331 in.)
Second [B] 0.82 0.84 mm
(0.0323 0.0331 in.)
Service Limit:
0.92 mm (0.036 in.)
Second 0.92 mm (0.036 in.)
...
Valve Guide Installation
Apply engine oil to the valve guide outer surface before
installation.
Heat the area around the valve guide hole to about 120
150°C (248 302°F).
NOTICE
Do not heat the cylinder head with a torch. This will
warp the cylinder head. Soak the cylinder head and
heat the oil.
Usin ...