Before the /5 series, BMW had a reputation for producing expensive and idiosyncratic touring motorcycles.But the /5 changed that. Although still expensive, the market was opened to a new world of riders, and during the 1970s the air-cooled boxer evolved into the ground-breaking R90S and R100RS.These were amongst the first motorcycles with factory-fitted fairings and they also offered class-leading performance.Even when BMW decided to discontinue the twins in favour of the new four-cylinder K-series in 1984, demand for the older boxers forced BMW to reconsider.The boxer was resurrected and continued for more than a decade.Freelance writer and author Ian Falloon has numerous motorcycle books to his name such as the Original BMW Twins, BMW R90S, BMW Story, Moto Guzzi Story and Laverda Twin and Triple Bible.He has a small collection of classic sporting motorcycles – including a 1976 BMW R90S.