I don't recall anybody of that name. Are you talking about a member of the Essex Roads? I knew only a couple of them , the Carr brothers , Lee and Bill. Bill spent a lot of time racing in Belgium with a string of good placings to his credit, and this at a time when competion was fierce to put it mildly. Keith Butler was
also riding as an amateur there and after several wins signed a contract with St. Raphael-Geminiani.
Practically all Essex Roaders used frames made by J.T.Braysher of Walthamstow although I seem to think Bill Carr used a Belgian frame when racing there, as british frames tended to shake themselves apart on the cobbles and generally rougher roads found in Belgium in the sixties. Ted Hookins was another Essex Roads star of that era, although I didn't know him but as a star-struck junior would admire him from a distance.
Getting back to Rory O'Brien, as has been mentioned in an earlier post, he was a keen yachtsman, especially on the Essex estuaries and coastal inlets.
He was also known to drive at high speed down to the South of France for short stays, whether he did any sailing there I don't know but there must be lots of people out there who knew him well and could fill in a lot of the spaces.
He was also a lifetime member of the Easterley Road Club. Perhaps that rings a bell for a few people?