Vintage BMW Motorcycle Owners

I'm not sure I can help directly with your questions, but I'll provide some other contacts that can likely help out. Try Vech at Bench Mark Works

http://www.benchmarkworks.com

Another source might be Chris at Barrington Motor Works; Chris is up in your next of the woods.

http://www.barringtonmotorworks.com/

Regarding putting the right frame with the right engine, check out this orphan list to see, if by chance, the serial numbers you have might belong somewhere else, or maybe you can find the numbers you need here.

http://bmwvmca.org/joomla/index.php?opt ... &Itemid=39

Kurt in S.A.

I have what may best be described as an R-series "Frankenbike" - a 655... series frame number (circa 1961 R69S) with a 552... series motor (circa 1956 R50). Unfortunately, I don't have the history of how these two came to be brought together.

So here's the question - are there any major differences I can look for in the fittings, sheet metal, etc. that would tell me if I have (A) a 1961 R69S with a transplanted R50 motor or (B) a 1956 R50 with a replacement frame from an R69S? Or is there really any difference between the two?

My thoughts are that if the rest of the bike is R69S, I should locate an R69 motor and bring it back as the more valuable R69S, otherwise it would make sense to leave it as an early R50...