Rik was, for over sixty years, an active participant in the Esperanto movement in Britain, and up to 1999 provided free legal services to Esperanto Association of Britain. In 2006 he took early retirement at the age of 80 as a solicitor practising in Leeds. In 2008 he resigned from Esperanto Association of Britain, stating that he had not left the Esperanto movement, but that the association had.
Rik was puzzled by the apparent use of artificial language projects, such as Ido and Interlingua, to undermine or attack Esperanto. There had been a historical culture in the Esperanto movement of ignoring such language projects, but Rik took the view that these issues should be addressed. He devoted himself to a systematic study of the introduction of both Ido and Interlingua, and was able to show, in both cases, that they had more to do with politics than linguistics.