Bostrom rode the Austin Ducati in the AMA Superbike Championship in 2004 and the Parts Unlimited Ducati in 2005. He was the sole AMA Superbike Ducati rider in 2004. Former Superbike World Champion Neil Hodgson joined the Parts Unlimited Ducati AMA Superbike team for the 2005 season. Bostrom's brother, Ben, took his spot on the Ducati team after Eric left for Yamaha after the 2005 season ended. By the end of the 2006 season, Ducati pulled out of all AMA competitions.