January 1st
Vintage motorcycles are those manufactured between January 1st 1920 and December 31st 1945 ~ HMCRRSA. (May differ in some countries)
From the Griffon Motors leather-bound souvenir booklet at the Stanley Show:
Full directions of "What to do on January 1st 1904," and space for entering special regulations, closed roads, etc., in the owner's particular district, are included.
Orlando Ghiro and Vittorio Zito riding Ceccato machines took 15 world records in the 75cc and 100cc classes.
CZ subsidiary CZ Cagiva established.