"Johnny Berry frames carried a serial number on either the left dropout or under the bottom bracket. From 1946 to early in 1953, the serial number on a Johnny Berry frame almost always was stamped somewhere on the outside of the left dropout. After early 1953, serial numbers were always stamped under the bottom bracket shell, parallel to, and near, the right edge. Forks carried a serial number under the crown that corresponded with the serial number that was stamped on the frame."
"Johnny Berry serial numbering was distinctive and is diagnostic. Typical Johnny Berry serial numbers had six digits that began with a "4", "5", "6", or "7”. The first two digits of the serial number represented when the frame was built (e.g., “47” = 1947). A “1” always followed the two digit date code. This “1” was always the fourth digit when reading from the right side of the serial number. A three digit, frame number followed the “1”; the frame number ran sequentially from when Johnny Berry began building under his own name in 1946."