Re:
Hi, if you assume that's a 'A' at the start of the serial number ( the fork should have it as well ), that would place it in 1939, my 39 flyer is A6352, I think the 41 may just be a 'painters' stamp, or a warranty fix by Carlton, just a few thoughts. Also, 'fixies' have been about since Victorian times so its not an issue, I'll be doing my flyer as a period time trail bike which will be fixed. Terry