Originally Posted by unworthy1

^beat me to it^
if you can read all the numbers (I can't) , perhaps check the "Asian Serial Numbers" thread and see what turns up:

https://www.bikeforums.net/classic-v...ber-guide.html


also looks to have had guides on the RH side of the TT for "split housing", but these have been drewed off. There's something on the NDS BB cup but can't read it, that should explain the threading and provide a BIG clue