Vintage BMW Motorcycle Owners

I have long wondered if there is any special significance to the number 75001 stamped on both of the barrels on my series 2 R16.

I went to the Knowledge Base link at the top right and then BMW Model Info. I typed 75001 into the engine number box and it found that those engine numbers seemed to have been used for the R16 and R63 models in the late 1920s and to 1934 for the R16. Do you suppose that's the significance?

Yes Thanks. I didn't phrase or word my question properly. The barrels are on my series 2 R16 but the barrel number is from the very first R63 ! I find this somewhat astonishing, The numbers look authentic and I can not see why anyone would bother restamping those. The numbers on my cylinder heads are correct and match the typenshield for a series 2 R16.

From the documentation I've seen, both the R63 and R16 engine numbers start with 75001. Not sure how that can be, but I'm guessing that at the beginning, that specific engine could be destined for either of the two models, so BMW couldn't state specifically. They made fewer R63 models.

I don't recall how BMW matched things early on...I know that frames and engines didn't match up until around or after WWII. As for engine numbering, one would think that they would all match. Is it possible that your barrels and cylinder heads didn't start out life together?

It looks like I have a set of barrels from the very first R63. Looking through my 1929 and 1930 literature it is evident that the R63 and it's side valve sibling the R62 were both made into 1929 the first year for the R11 and R16 which would account for the overlapping of numbers for the different models . In both the 1929 and 1930 sales catalogues in the fine print it states that a tubular frame could be had if desired instead of the new pressed steel ones so were they trying to get rid of the earlier type frames to add to the confusion for later day restorers!