Gubby's single attempt to participate in a Formula One World Championship race, the 1965 British Grand Prix at Silverstone, also ended with problems in practice. At the Woodcote corner, his Lotus jumped out of sixth gear at 170 mph, and Gubby was forced to hold the gear lever in position whilst cornering at high speeds. He decided there and then to retire from the sport, and did not attend the following day's practice session. He later recalled, "I was driving on a shoestring, and I thought to myself, 'Brian, you've got a family to look after and you'll end up killing yourself.'" He had entered the 1965 Mediterranean Grand Prix, but withdrew his entry and sold his Lotus to Stirling Moss for use by a film company working with Steve McQueen.