BSA Gold Star

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1956 BSA Gold Star DBD34
Manufacturer Birmingham Small Arms Company(BSA)
Predecessor 1955 BSA Gold Star DB34
Successor 1971 BSA B50
Class Clubmans racer
Engine alloy air cooled ohv 499 cc single cylinder
Transmission 4-speed gearbox with wet multiplate clutch
Wheelbase 56 inch[1]
Seat Height 30.5 inch[1]
Fuel Capacity 4 gallons[2]
Related BSA B33
Similar Manx Norton, Matchless G50, Velocette Venom

The BSA Gold Star, (1938 - 1963), was a 350 and 500 cc 4-stroke production motorcycle that gained its reputation for being one of the fastest machines of the 1950s. These motorcycles were popular for their high performance. Besides being hand built, with many optional performance modifications available, they came from the factory with documented dynamometer test results, allowing the new owner to see the horsepower produced.

Contents

[edit] Origin

In 1937, Wal Handley lapped Brooklands at over 100 mph on a BSA Empire Star, and was awarded one of the traditional Gold Star pins for the feat. That inspired BSA to produce the BSA Gold Star.[3]The first Gold Star was an M24. It had an alloy 496 cc engine, an Electron alloy gearbox, and a light tube frame devoid of side-car lugs. This model continued up till the War.[4]

[edit] 1948 ZB32

After the war the all alloy 348 cc B32 Gold Star was released, with an very large list of optional components. Once ordered the bike was assembled by hand, and the motor bench tested. They were 20 lb lighter than the comparable cast iron barrel and head B series single. They were very successful in the 350 class from 1949 to 1956. They could be specified in tourer, trials, ISDT, scrambles, racing or Clubmans trim.[4] The ZB is taken from the beginning of the engine number.

[edit] 1949 ZB34

The 499 cc B34 Gold Star had a modified crankshaft and a different design main bearing. The 350 continued. In 1950 both received larger front brakes. In 1952 the 500 gets a new Bert Hopwood design head, and the 350 had a new head of that design the following year.[4]

[edit] 1953 BB34 and BB32

In 1953 a swing-arm duplex frame is introduced, along with an improved gearbox.[4]

[edit] 1954 CB34 and CB32

An optional CB motor was given more and squarer finning, stronger crank, a shorter conrod, oval flywheels (500), improved valve gear, and an Amal GP carb.[4]

[edit] 1955 DB34

The DB Gold Star had an improved oil feed to the crankshaft, and finned front brakes. If the buyer specified Clubman cams and timing, he also received a special silencer. At the end of this year the BB and CB models were discontinued.[4]

[edit] 1956 DBD34

The most prized model was the 500 cc DBD34 introduced in 1956, with clip-on handlebars, finned alloy engine, polished tank, 36 mm bell-mouth Amal carburettor and swept-back exhaust. The DBD34 had a 110 mph (177 km/h) top speed. The Gold Star dominated the Isle of Man Clubmans TT that year. Production ended in 1963.[5]

[edit] 1963 End of production

Towards the end the Gold Star was only offered in scrambles, or Clubmans trim. In 1963 Lucas ceased to produce the magneto used in the B series, and that line of singles was ended.[4] A sporting single was not produced again till the BSA B50 models that were produced from 1971 through 1973. Some remaindered stock were marketed in 1974 as Triumphs, and later CCM used BSA B50 bottom ends in their early specials.[6]

[edit] Sources