A wartime design by Erling Poppe, the Sunbeam inline twin was introduced by BSA, owners of Sunbeam Cycles Limited, in 1947. A luxury tourer inspired by the pre-war BMW, it was of advanced specification with overhead-camshaft engine, shaft drive and plunger rear suspension. The clutch housing and four-speed gearbox bolted directly to the back of the engine, which was rubber mounted in the duplex loop frame, an innovation that required a flexible joint in the exhaust system ahead of the silencer. The first S7 version was equipped with balloon tires, a feature not carried over to the deliberately more conventional, and also lighter and cheaper, S8 introduced in 1949. The front fork and 7" brake were now standard BSA components and there were numerous other changes made in the interests of rationalization. Never as popular as BSA's more performance orientated models, the gentlemanly S7 and S8 remained in production until 1957.

The early S7 offered here dates from 1948, a time when the design was still undergoing alteration and refinement, and has the ratchet center stand offered for that year only. Last of the many motorcycles restored by the vendor over a lengthy career, it was completed in 2009 and is described as 'a great fun runner, not quick to get up to speed but will run at 60-70mph all day long.' A brand new pillion seat (never mounted) comes with the machine.