If there are notches worn into the splines, replace the sub clutch hub. Also, replace the steel plates if their teeth are damaged.

Clutch Housing Finger Inspection
Damper Cam InspectionTightening Sequence
Generally, when installing a part with several bolts, nuts,
or screws, start them all in their holes and tighten them to
a snug fit. Then tighten them according to the specified sequence
to prevent case warpage or deformation which can
lead to malfunction. Conversely when loosening the bolts,
n ...
Exploded View
11. ZX1000JD/KD
AD: Apply adhesive.
AL: Tighten the two clamp bolts alternately two times to ensure even tightening
torque.
G: Apply grease.
L: Apply a non-permanent locking agent.
Specifications
...
Shift Pedal Installation
Install the rubber damper to the shift pedal.
Turn the chamfered side to inside.
Assemble:
Shift Lever [A] and Locknut [B] (Left-hand Thread)
Shift Pedal [C] and Locknut [D]
Tie-Rod [E]
Turn the grooved end [F] of the tie-rod to the shift lever.
Apply grease to the sliding ...