Oil with friction modifiers should make it slip not stick. Mine was clunking pretty bad when it was cold and had sat for a while. Om the last oil change I used a quart of Valvoline synthetic along with my usual oil.
I rode it hard and let the clutch slip a couple times, It got better, someone else recently reported success with,,, was it Bardahl? something like that. An old school additive. I bought whatever it was, I'll check the garage.
