Harley and Davidson did indeed start their company in 1903 in Milwaukee. By 1910 (when the episode is set), they had already released their first production bikes and built their first factory.
The episode is famous among fans for its numerous "Easter eggs" and references to motorcycle culture: [S16E5] Murdoch Rides Easy
The episode pokes fun at the lack of safety equipment in the era; motorcycle helmets weren't seriously researched until after the death of T.E. Lawrence in 1935. ⭐ Fan & Critical Reception Harley and Davidson did indeed start their company
The script frequently references 20th-century motorcycle films, most notably Easy Rider (1969), through its title and dialogue. most notably Easy Rider (1969)