During the first years of his partnership with Bond, Miller withdrew his partnership from his sailmaking company but its name was retained. Soon after the 1974 Cup challenge, Miller changed his name to Ben Lexcen to avoid confusion with the company. It is unclear why he chose this name.
Bond and Lexcen challenged for the America's Cup in 1977 (against media mogul Ted Turner) and 1980, losing both times.
Lexcen realised that to stand a chance of winning against the defenders with their 100+ years of America's Cup winning experience needed a superior boat. So he designed a winged keel that was designed to make a boat more stable and maneuverable in the water. The keel design, which borrowed elements from aeronautics, was to prove highly controversial.
Australia II was a revolutionary design approach with the winged keel and also the shortest waterline length ever measured on a 12-metre. The American defenders formally protested but Australia II complied with both the 12-metre class rules and the America's Cup rules and hence the protests were rejected by the America's Cup Committee and Australia II was allowed to race. A key part of the protest was that the keel was a Dutch design and not an Australian design.
The 1983 America's Cup saw Lexcen's Australia II, with John Bertrand at the helm, take on the NYYC skipper Dennis Conner and his yacht, Liberty. The Australians were sure they had a fast boat but the intense pressure of continuous failure by challengers who rarely won a single race possibly caused Australia II to lose the first two races. However Australia II stormed back to take four of the last five. This was the first time in history that the series depended on the result of the last race and the pressure was now firmly on the defenders. In the deciding race on 26 September, the pressure showed and Dennis Conner made an uncharacteristic tactical error and Australia II won becoming the first challenger to wrest the Cup from the United States since its inception in 1870. Lexcen was made a Member of the Order of Australia for his contributions to the winning effort.
Lexcen was commissioned by Bond once again in 1986 to design a defender for the 1987 America's Cup. Australia IV, Lexcen's final design, was defeated by the Iain Murray-designed and skippered Kookaburra III in the Defender Trials and did not compete in the Cup that year. Australia competed in the Cup without Lexcen as their designer for the first time in ten years and were humbled by the American challenger, Stars & Stripes, 4 races to 0.
In 2006, Lexcen was posthumously inducted into the America's Cup Hall of Fame.