Like Msocko said.....its the clutch plates sticking. Example........hold your clutch in for 30 seconds when you first start up your bike for the day.....drop it in gear and ill bet you the famous HD clunk didnt happen.
Thank you, thank you, and thank you. tried that today and it works. Held clutch lever pulled in for 30 seconds+/-, then shifted. A much reduced clunk and it sounded and felt normal. It is always good to ask the experts. Will follow this procedure from now on. Great advice.