I was at a classic British motorcycle restoration shop last weekend (it was totally awesome by the way) and I mentioned that my BSA has matching frame/engine numbers. He was suspicious and said it can't be right and must have been forged somehow. I felt like telling him he doesn't know much but thought better
It was even nearly all of the BSA's with WM20 prefix that had matching numbers. Of the 120.000 + made at least 110.000 left the factory with matching engine and frame numbers. When you take a look at the frame number page of the website you can see that quite a few still have matching numbers today.
I actually think that there are amazingly many with matching numbers. When I just started this list I only knew about bikes with non matching numbers but when more and more people started sending me their engine and frame numbers I found out that specific locations had relatively many bikes that still had their original engine. Australia and New Zealand both have quite a few matching number BSA's, while in Holland there are only a handful.
With that list a few frames and engines have been reunited and that is pretty cool I think, some were continents away from each-other. Of course I also started the list to find the engine for my BSA with frame number WM20 80052 but that didn't happen yet. That bike is sold now but I am sure Ramon will still be interested to get that engine.