1924 Ace Motorcycle
April 12, 2010 12:00 AM
After selling his company to bicycle magnate Ignaz Schwinn, William G. Henderson struck out on his own in 1919, founding the Ace Motor Corporation in Philadelphia. There he rebooted his dream of building the perfect four-cylinder motorcycle, and wound up creating the world's first superbike. The Ace XP-4 would set a speed record of a whopping 129 mph in 1923, and would eventually be folded into the Indian product line when the company was sold for the last time in 1927.