BS90 Serial Number questions

[buzzard]

So having purchased a BS90 this past  weekend , I thought I was clear on the year...now I am not so sure. The guy I bought it from had had it for over 40 years and said it was a 67. When we looked at the original registration it said it was a 69. I read all info on the serial number thread in the forum and looked at Graham's serial number explanation but it didn't get me much further. The number on the registration papers says 125047874 ...which seems to be one to many digits.

So any help would be appreciated, firstly,  where on the chassis would you find the serial number plate , if indeed it is still there. Second is the number itself ...is it recorded wrong on the papers...could the fourth digit be an O not a 0 .

[moonpup]

More than likely, it's the 3rd digit that is incorrect and instead of being a 5, it was probably an "S". That would mean your bike was produced in July of 1965.  (see pic)

[buzzard]

I think you are very likely correct , thanks for solving the mystery , much appreciated.