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

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Sidestand Installation
Replace the sidestand nut [A] with a new one.
Apply grease to the sliding areas [B].
Tighten the sidestand bolt [C] first, and then the sidestand
nut.
Torque - Sidestand Bolt: 44 N·m (4.5 kgf·m, 32 ft·lb)
Sidestand Nut: 29 N·m (3.0 kgf·m, 21 ft·lb)
Install the spring [D] as sh ...
Tire Installation
WARNINGSome replacement tires may adversely
affect handling
and cause an accident resulting in serious injury
or death. To ensure proper handling and stability,
use only the recommended standard tires for
replacement, inflated to the standard pressure.
Inspect the rim ...
Front Fork Disassembly
Remove the front fork (see Front Fork Removal (Each
Fork Leg))
Drain the fork oil (see Front Fork Oil Change).
Take the dust seal [A] off the outer tube.
Remove the retaining ring [B].
Separate the outer tube from the inner tube.
Remove the following parts from the inner tube. ...