Son of top British sidecar racer Chris Vincent, Jay won the British 250cc Championship in '94 and was 2nd in the European Championship in '97. He entered the World Championship in '98, when he took 5th place in the 250 races at Sachsenring and Le Mans. He repeated his best ever result in 2000 at Donington, having led the race in the early stages, and was signed up by Pulse to head their ill-fated 500 project in 2001. Despite disappointing results, which saw the team fold midway through the season, Vincent's quality was recognised by Red Bull Yamaha, who asked him to replace the injured Garry McCoy for the British GP.