Book excerpt: Part of the acclaimed Original series, Original BMW Air-Cooled Boxer Twins presents BMW's most famous motorcycles in exquisite detail. The book focuses on the post-1969 /5 and newer series, paying particular attention to such groundbreaking models as the R75/5, the R90S, the R100RS, and the R80G/S. The book also covers the earlier models in a chapter focusing on the Earles fork machines.