Try flushing and bleeding the clutch. Pull the slave off and withdraw the clutch rod, roll the rod on a table, is it straight? While you have the slave off inspect piston for scoring. What kind and how heavy of oil? Might be a soft spring, try adding a shim/washer under the lock nut, might help some also. Could be your 30 year old clutch is due for a change.
93 VT1100C Sleeper, VH Exhaust, Saddleman Seat, Baby Apes, Metzlers, 2mm sleeved and bored (1150cc),10.5:1 comp, Modified Heads, Valves, Cams, Adjustable Timing, Bored Carbs.