Dick Gale '6O suits up to ride his Italian-made Bimota to San Francisco's finan-cial district, where he works as a stockbroker for Morgan Stanley Dean Witter &Co. A long-standing member of the exclusive Montgomery Street MotorcycleClub, which celebrated its 30th anniversary this summer, Gale often turns headswhen he arrives at the office, stripping off his helmet and windbreaker to reveala blue pin-striped suit and yellow power-tie.