Displacement: 557 cc
Engine type: 4-stroke / sv
Frame number: B1371
Engine number: R1303
Originally established in 1861 as an armaments manufacturer, The Birmingham Small Arms Company switched to making components for the bicycle industry in 1878 following a Government-induced downturn in the arms market. BSA first experimented with powered two-wheelers in 1905 using a standard-type bicycle. This first motorcycle made by BSA used a proprietary engine - probably the Belgian Minerva - clipped to the front down-tube, but it was not until 1910 that the firm introduced a model entirely of its own design and manufacture. Displayed at that year's Olympia Show, the first series-production motorcycle to feature the marque's distinctive green and cream tank colours was a 499cc (3½hp) sidevalve single, built initially with single-speed, belt-drive transmission and later on with a three-speed countershaft gearbox. Well engineered and equally well made, this first BSA proved an enormous success and changed little over the next few years, though for 1912 a two-speed hub gear was available together with an all chain drive model suitable for sidecar work. For 1914 the range was augmented with a 557cc (4¼hp) long-stroke version featuring a strengthened frame and the new three-speed gearbox, which was designated Model K if fitted with chain-cum-belt transmission or Model H with fully enclosed all-chain drive.
This BSA H 557cc has the appropriate engine for sidecars. It has with its Watsonian sidecar many of charm, lovely details and patina. The engine do his job very well and runs smooth.