RMS37 is right on the money with that one...Excelsior Cycle Supply ran from the late 1800's through 1936 when D.P. Harris bought the place... then turned into Excelsior MFG. CO. after that... stayed open until the mid 60's I believe. Most of the bikes that came out of there after 36' were labeled as Hawthornes or Rollfasts... I never saw one after 36' actually labeled as an Excelsior other than on the headbadge. btw... I have a frame for that tank...actually most of the bike, let me know if your interested.