BSA Motorcycles were made by BSA Cycles Ltd, under the BSA parent up until 1953 when the motorcycle business was moved into holding BSA Motorcycles Ltd.
BSA motorcycles were sold as affordable motorcycle with reasonable performance for the average user. BSA stressed the reliability of their machines, the availability of spares and dealer support. The motorcycle were a mixture of sidevalve and OHV engines offering different performance for different roles, e.g. hauling a sidecar. The bulk of use would be for commuting. BSA motorcycles were also popular with "fleet buyers" in Britain, who (for example) used the Bantams for telegram delivery for the Post Office or motorcycle/sidecar combinations for AA patrols The Automobile Association (AA) breakdown help services. This mass market appeal meant they could claim "one in four is a BSA" on advertising.
Machines with better specifications were available for those who wanted more performance or for competition work.
Initially, after World War II, BSA motorcycles were not generally seen as racing machines, compared to the likes of Norton. In the immediate post war period few were entered in races such as the TT races, though this changed dramatically in the Junior Clubman event (smaller engine motorcycle racing over some 3 or 4 laps around one of the Isle of Man courses). In 1947 there were but a couple of BSA mounted riders, but by 1952 BSA were in the majority and in 1956 the makeup was 53 BSA, 1 Norton and 1 Velocette.
To improve US sales, in 1954, for example, BSA entered a team of riders in the 200 mile Daytona beach race with a mixture of single cylinder Gold Stars and twin cylinder Shooting Stars assembled by Roland Pike. The BSA team riders took first, second, third, fourth, and fifth places with two more riders finishing at 8th and 16th. This was the first case of a one brand sweep.
BSA Motorcycles BSA Royal Star
The BSA Royal Star is a British motorcycle that was a radical new design for BSA that paved the way for a whole range of very successful unit construction twins. As well as giving a clean look to the engine, with the pushrod passages part of the cylinder block casting, unit construction reduced the number of places oil could leak from.
Bob Fearon, Managing Director and General Manager of BSA recognised the need for a completely new look that built on the best features of the A10's but would succeed in the potentially lucrative but competitive United States market. Working with Chief Development Engineer Bert Perrigo they developed the unit construction Star twins. Launched in 1962 the as the 500cc BSA Star and later the more sporty Royal Star The model was widely exported to the USA and Australia as well as becoming a top seller in the UK in the early 1960s.
The Royal Star had a relatively small single Amal monobloc carburettor, and later Concentric carburettor, but in 1964 new pistons and a new gearbox improved performance. The machine had a top speed of about 90 mph and was relatively free of vibration.
BSA Motorcycles BSA Spitfire
The BSA Spitfire is a Birmingham Small Arms Company BSA motorcycle made from 1963 to 1968. One of the first BSAs to have 12-volt electrics, the Spitfire was also one of the first "street racers" with two large-bore Amal GP carburettors, complete with velocity stacks.
In 1966 BSA motorcycles were starting to experience financial problems and the management decided to rationalise the range to just six motorcycles. The A65 Spitfire motorcycle was one of these and had a number of new features including a new twin-downtube steel frame and new Girling shocks. A 190mm front drum brake improved braking and lightweight alloy rims reduced the weight to 174 kg. Two large-bore Amal GP carburetors with velocity stacks improved acceleration but made the Spitfire hard to kick start when the engine was hot, so owners chose to replace them with Amal concentric carburettors with more conventional round air filters and this became the factory supplied specification in 1967. Keen to boost sales in the US market BSA produced a special Spitfire with a two gallon fuel tank following the trend set by the Harley Davidson Sportster. The UK Spitfire had a conventional four gallon tank, with a large five gallon option from 1967.
The BSA Bantam range of two-stroke engines introduced the unit construction concept to BSA since its introduction in 1949. BSA produced their first four-stroke unit construction singles in 1959 when they introduced the C15 to replace the venerable c12 single. The unit construction (in contrast to the separate engine and gearbox of the C10/C11 and c12) gave the family of motorcycles started by this model its familiar name.
The C15 was intended as a utility "get to work" model, and served this purpose faithfully for many thousands of users. It was a simple and reasonably robust design.
Along with the C15 came the B40, the 350 cc version. This was no faster than the C15, but had a little more lugging power. A version of the B40 was also produced (in considerable quantities) for various branches of the military. These bsa motorcycles (known as the "Ex-WD B40") were more rugged than the vanilla version (in particular, the timing-side main bearing was over- rather than under-engineered and an oil filter was fitted), slightly de-tuned and given a version of the competition frame. For these reasons, these bikes and Royal Enfield Motorcycles can make very good buying, and are often used as the basis for a BSA Motorcycles competition machines.