Upon graduation in 1979, Erik joined Harley-Davidson in the Test Engineering department. He worked in a series of positions at Harley-Davidson, including Product Engineer, Project Engineer and Senior Project Engineer. Although offered a Chief Engineer position in 1983, Erik Buell left Harley-Davidson at that time to build his own Buell motorcycles.

In 1993, Harley-Davidson acquired 49 percent of Buell Motorcycle Company, Inc., and in 1998 Harley-Davidson Motor Company purchased controlling interest. Erik became part of the leadership team at Harley-Davidson as well as Chairman and CTO at Buell. Sales for Buell grew continuously through 2009, at which time Harley-Davidson had a massive restructuring due to the recession, closing several plants, selling MV Agusta, and closing Buell.

Shortly after the closing of Buell, Erik started Erik Buell Racing, Inc., and in three years built it into a multifaceted company which had: a division that races at the highest level in the US, a division producing EBR brand motorcycles, and a division providing high end engineering design and development consulting services. This company was shut down in 2015.