Weishaar was racing on the national circuit by 1914, with the national event in Savannah, Georgia being his first big race. He was forced to drop out of the race on the 24th lap when his gas tank began leaking; at the time he was vying for the first-place position. In 1915, at the Dodge City 300, a malfunctioning spark plug caused him to lose, and he also lost a 300-mile race at the Chicago Speedway due to his helmet strap coming loose, but that same year he claimed a victory in a 100-mile race in Pratt, Kansas.