BMW (Bayerische Motoren Werke) is a very unique manufacturer of motorcycles. The heritage of precision German engineering has long been established as top of the line in engine development and manufacturing. BMW had early beginnings, as far back as 1917, building airplane engines with funding from the German Air Force. BMW was very good and profitable at it.
BMW began as two separate companies: Flugzenmaschinenfabrik (Airplane Factory) and Flugwerke Deutschland. They merged on March 7, 1916 to become the Bayerische Flugzeugwerke (Bavarian Airplane Works). Their original approach to engine design helped them become very popular with the German military, and basically helped manufactured the German Air Force. This included the world famous Red Baron, (Baron von Richthofen).
On July 21, 1917 the Bayerische Flugzeugwerke is changed to the Bayerische Motoren Werke (Bavarian Motor Works), and their most popular product was the V-12 airplain engine.
The end of WWI in 1919 brought not only peace, but it also brought a ban on Germany to build airplanes. This same fate would later await several Japanese companies after WWII, who were not yet involved in motorcycles.
In order to continue to sustain the company, BMW’s head designer, Max Friz, began designing motorcycle and automobile engines. Within a month he had created a design for the opposing flat twin cylinder engine, affectionately known as the “boxer” engine. The first boxer engine, based on a British Douglas design, was built by 1923.
The boxer opposing flat twin engine has the cylinders arranged at opposite sides of the crankshaft. Typically, cylinders are arranged in a V formation with the cylinders basically above the crankshaft, or sometimes side-by-side on the same side of the crankshaft. The opposing twin has nearly perfect balance, both horizontally and vertically.
Along with the balance you get with the flat twin, you also get a low center of gravity which makes the bike easier to ride and handle. Unfortunately, the width of the flat twin reduces the amount of lean angle you are able to achieve. In order to remedy this, you need to mount the engine higher on the frame, effectively eliminating the advantage of the lower center of gravity.
BMW is a very well established and trusted motorcycle manufacturer. They have some of the longest history in motorcycles and proven expertise in engine design and manufacturing.