 BMW Motorrad began manufacturing RT ("Reise-Tourer", or travel tourer) touring motorcycle models in the late 1970s.The first of these were air-cooled (or "airhead") models that continued BMW's long tradition dating to 1923 of producing "boxer" or opposed flat-twin engined motorcycles with unit engine-transmission construction and shaft final drive.In 1995, BMW produced its first air and oil-cooled (or "oilhead") RT model, the R1100RT.