The BMW R12 was an evolution of the iconic R7 concept and it was the first motorcycle in the world with hydraulically damped telescoping forks. BMW produced roughly 36,008 over a production run between 1935 and 1942.
The R12 was powered by a 750cc boxer twin pushing either 18 or 20 horsepower (depending on if it had one carb or two) through a 4-speed transmission and shaft final drive. Claimed top speed was either 68 or 75 miles per hour (again, depending on the number of carbs). It weighed 357 pounds dry and had a 3.7 gallon fuel tank. Shifting was handled with a lever on the right side of the tank.
This example has been restored, the seller claims that it’s numbers-matching. He doesn’t have much else to say, though it’s noted that he has lots of photos from the restoration process. I appreciate that he’s included a startup video of it:
Find this R12 for sale in Ostrów Wielkopolski, Poland with a BIN of $46,000 or best offer here on eBay.