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. 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.