Resurrecting an old thread.
I was thankful to nicholsonj2252 for trying an unsuccessful vin test for me.
I remained interested in finding the missing 10 digits when only the last 7 are known from the frame number VIN.
I did find some reference to this on Snowbum's info and a motorcycle identification handbook:
https://www.thisoldtractor.com/mg_manuals/book_motorcycle_identification.pdf
For bikes built from 1981 to 85 (my G/S):
W = country of origin W Germany
B = BMW
1 = Motorcycle
0 = 2 wheels
364 = model
X = check digit
B = Year 81 (C = 82 etc)
6 = Munich or 9 = Berlin
Followed by sequential production numbers.
I figured my 81 G/S to be:
WB10364X9B9 + 7 digit frame number
I put these digits with my frame number into the few free vin checkers I found to be working.
Unfortunately these did not give me an answer and alerted me that only digit 9 (the year code was wrong!).
I would be interested to know if anyone can get this system to work for their bike or bikes.
Thanks
Gerry