A Brief History of the Marque
Wikipedia NL, quoting as source the work of S. Ewald / G. Murrer, states that the BSU was founded by Ugo Siniscalchi and produced motorcycles using using Blackburne 350cc engines in 1923 only.
According to MC Storico Conti, these motorcycles were built by the firm of Ugo Siniscalchi in 1943 until possibly 1945, reportedly using vertical single cylinder Blackburne engines of 350cc. However, as Blackburne production did not continue beyond the 1930s and British imports were actively discouraged during the fascist era, this information appears erroneous.
Sources: MC Storico Conti, Wikipedia NL, et al.
