Calven bought the family firm, L.W. Bonney and Sons Ltd, in 1984.
Calven was a founder of the Road Transport Forum and has been a board member since its inception. He was the Road Transport Forum Chairman from 2000 to 2002. He has been on the executive committee of National Road Carriers since 1974 and is a past president.
Calven was made a Member of the New Zealand Order of Merit in 2017 in recognition of his contribution to the trucking industry and motorsport.