If they appear damaged or deteriorated, replace them.

Balancer Adjustment
Torque LimiterWheel/Tire Damage Inspection
Remove any imbedded stones [A] or other foreign particles
[B] from tread.
Visually inspect the tire for cracks and cuts, and replace
the tire if necessary. Swelling or high spots indicate internal
damage, requiring tire replacement.
Visually inspect the wheel for cracks, cuts and dents ...
ZX1000JB/KB Models
1. Run the fuse box 2 lead in front of the rib for the fuse box 2.
2. Seat Lock Cable
3. Hook the licence plate light lead and the left turn signal light lead on
the projection of the tool
kit case.
4. Rib for Fuse Box 2
5. Run the starter relay lead in back of the rib for the fuse box 2 ...
Air Intake Solenoid Valve Unit Test
Remove the air intake solenoid valve (see Air Intake Solenoid
Valve Removal in the Fuel System (DFI) chapter).
Set the hand tester [A] to the × 1 Ω range and connect it
to the air intake solenoid valve terminals as shown in the
figure.
Special Tool - Hand Tester: 57001-1394
...