Most of his works were for the motorcycle industry, especially for motorcycle magazines. His art was reproduced as the magazine center spread beginning in 1973 and continued to be the publication's heart until he was forced to retire in 2003 because of his failing health. A collection of Mann's work was published in 1993 and updated in 2004.
One of Mann's frequent motif was a motorcycle and rider with a complementary or contrasting figure. The simplest form is the iconic image of two bikes on the road next to each other, and out of this grew varieties that spanned 30 years.
