Not my write up. I nicked it from http://www.retrothing.com/2009/08/the-art-deco-bmw-motorcycle-that-time-forgot.html
What an amazing looking BMW Prototype. In fact BMW have restored this bike and I have seen photos of it being ridden. Looks like it came right out of a Batman movie.
The sheer beauty of the BMW R7 prototype takes my breath away. A single copy was crafted in 1934 by design engineer Alfred Böning. His vision was a departure from the “bicycle with motor” design still prevalent in the 1930s. The R7 incorporated sweeping enclosed bodywork, a pressed steel frame, valanced mudguards and then-innovative telescopic front forks.
The R7’s beauty was more than skin deep, however. The transmission featured an ‘H’ pattern hand shifter and the 800c Boxer engine crafted by Leonhard Ischinger was decades ahead of its time. The revolutionary engine includes a forged, single piece crankshaft. The cylinder housing is a monoblock with a hemispherical combustion chamber, eliminating the need for a troublesome head gasket and the camshaft is positioned below the crank (allowing more convenient plug placement).
Alas, the R7 was deemed too extravagant and expensive to produce in the harsh economic and political climate of the mid-1930s. The roadworthy prototype was stripped of useful parts, crated and largely forgotten until 2005. When the box was finally opened, the R7 was found to be 70% complete but in disastrous condition. Many components were severely rusted and a long-forgotten battery had ruptured and corroded the machine even further.
Luckily, the original design drawings were located in the BMW Archives and BMW Classic undertook a comprehensive restoration. A team of specialists rebuilt the frame, bodywork, transmission and one-of-a-kind motor. By the end of 2008, the machine looked like it must have when Alfred Böning first rolled it out of his Munich workshop. It performed flawlessly on its first road test in over 70 years and, hopefully, will be displayed around the world in years to come. [thanks, Karen!]