Mr McDiarmid, from Nairnshire, died after being involved in a crash with a Ford Transit van at around 7.45pm on June 29.
The incident happened on the A82, south of Inverness at the junction for the Loch Ness Country House Hotel.
Mr McDiarmid was pronounced dead at the scene and his family have asked for their privacy to be respected during this difficult time.
Police Scotland issued an appeal for information after the accident to help establish the full circumstances around it.
Sergeant David Miller, of Police Scotland’s Highlands and Islands Road Policing Unit, said: “Our thoughts remain with the family of Mr McDiarmid and enquiries continue into the full circumstances of what happened.
“Anyone with information that could help is asked to call 101, quoting incident number 3159 of Tuesday, 29 June, 2021.”