BMW R12
The R12 was an air-cooled boxer twin four-stroke motorcycle produced by BMW from 1935-1942.
The R12 along with its sister model, the R17 were milestone models in the evolution of motorcycling, being the first production machines to feature a hydraulically dampened telescopic front fork. This resulted in the R12 being the best selling pre-WWII BMW motorcycle, with 36,000 units sold from 1935 to 1942, with a great many going into military service.