The Ace Motor Corporation was an American motorcycle manufacturer that had a short life, but a profound impact on engine design – especially for the Indian Motorcycle Manufacturing Company who acquired Ace in 1927.

Ace was started by William G. Henderson in 1919, he’d sold his first motorcycle company (Henderson) to Excelsior in 1917, and kept working there until 1919 by which time differences in opinion led to him leaving.

He had pioneered the design of the early straight-4 engines used in Henderson motorcycles and he brought this expertise to Ace, although he had to be exceedingly careful not to infringe on any of Henderson’s patents – which he had actually filed himself just a few years prior.

The first Ace Four rolled off the production line in 1919 and the company saw some success competing with the likes of Indian and Henderson. Tragically, William G. Henderson was killed when testing an Ace prototype in 1922 after being struck by a car. His untimely death left the company on shaky ground but it persisted and even set a new motorcycle land speed record a year later in 1923 when Red Wolverton rode a modified Ace XP-4 at 129 mph.

The Ace Motor Corporation was so certain that no one could match this record that they offered the “Ace Speed Trophy” and a handsome cash prize to any person or company who could break the record. The trophy was never claimed.

The Ace Four you see here has a capacity of 1229cc (307.25cc per cylinder) and is a 1927 model – making it one of the last ever produced.

Indian acquired Ace in 1927 and began utilising the straight-4 in their own motorcycles, this spelled the death knell for Ace however, and the marque would be discontinued in the same year.

All Ace motorcycles had the same basic engine, a reliable air-cooled unit that feeds power to the rear wheel via a 3-speed, hand-operated transmission and chain drive. Henderson was only in his 30s when he designed the engine, and he’s remember today as an engineer that was far ahead of his time. He had designed a very reliable power-unit in the straight-4 used by Ace, to prove this the company sent Erwin G Baker (famous for his record-breaking long distance rides) on a transcontinental Cannonball – he set the new record at 6 days, 22 hours and 52 minutes – far ahead of the record held by Henderson.

The short production life of the Ace Motor Corporation and the relatively low numbers of bikes produced means that they’re now highly sought after, although surprisingly it’s still possible to buy one for less than a king’s ransom. The blue Ace Four you see here is valued at between £18,000 and £24,000, and is due to be sold at The Spring Stafford Sale on the 26th of April 2015. If you’d like to read more about it or register to bid you can click here to visit Bonhams.

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Published by Ben Branch -