BSA Gold Star Clubman (1956) Weight, Brakes type, Top speed, Pics

                      BSA Gold Star Clubman

                                        For a competition-hungry motorcyclist in the 1950s, a Gold Star DBD34 Clubman was arguably the ultimate machine, whether for racing on the Isle of Man, on short circuits or on the street in unofficial burn-ups between coffee bars. Lean, purposeful and unmistakably aggressive, the DBD34 Clubman was the last, fastest and best known version of a series of Gold Star singles that included 350 and 500cc bikes in touring, trials and scrambles form.

Unmistakable appearance

                                         Its look was unmistakable: chrome-panelled fuel tank with BSA’s famous star-in-a-red-circle badge, headlight jutting up above a narrow pair of clip-ons, swept-back exhaust pipe leading from a heavily finned vertical cylinder. And the performance was unique, too. First gear was good for no less than 60mph (97km/h). With the rider’s chin brushing the big steering damper knob, the ‘Goldie’ had a genuine top speed of over llOmph (177km/h).

                                               The Gold Star story began in 1937, when racer Wal Handley earned a Brooklands Gold Star award for lapping the banked Surrey track at over lOOrnph (161km/h) on BSA’s 500cc M23 Empire Star. In the following year BSA produced a replica marketed under the name M24 Gold Star, the name signifying that each machine had been built using selected components, tuned and dyno-tested. with polished ports, conrod and crankcases.

                                       That first Gold Star also had magnesium gearbox casings and aluminium cylinder head and barrel. Power output was 28bhp when fuelled by petrol, or 33bhp when tuned to run on alcohol. Buyers received a certified dyno chart from their machine, a custom that was maintained with Gold Stars throughout. But BSA management decided

                                                  There were few more exciting bikes in the 1950s than a well-set-up Gold Star Clubman, which combined engine power with light, agile handling and powerful braking.

                                                This 1956-model DBD34 Clubman has all its go-faster components present and correct, including low clip-on bars, rear set footrests, filterless Amal carburettor and free-breathing megaphone exhaust. Not to mention the free-revving engine whose 42bhp peak output gave a top speed of well over lOOrnph (161km/h).

                                            That to reduce costs the sports Gold Star should resemble the standard single as much as possible, so its chassis was relatively standard.

                                         After the Second World War, BSA produced a competition bike called the B32, based on its pushrod single the B31. This was initially made for use in trials, but when fitted with an aluminium cylinder head and barrel its racing potential was clear. For 1949 BSA introduced the 350cc ZB32 Gold Star, followed a year later by the 500cc ZB34. Both were rapid, competitively priced and came with various options - four camshafts, three different sets of gears (standard, scrambles and racing), four compression ratios (for use 'with different fuels), and choice of fuel tanks, exhaust systems and wheels.

                                           Suddenly the clubman racer had a machine well suited to road and track. At the TT in 1949, Harold Clark averaged over 75mph (121km/h) on a ZB32 to win the Junior Clubman’s race, and in following years the Gold Star dominated both the 350cc Junior and 500cc Senior. In the 1955 Junior, no fewer than 33 of the 37 riders were on Goldies. But BSA's supremacy led to the Clubman’s TT being dropped after the following year.

Competition wins

                                               In 1956 BSA introduced the DBD34, which benefited from a development programme that had seen factory aces including Bill Nicholson ride Goldies to many wins in scrambles and trials. Competition-proven modifications, including steeper steering geometry, swingarm rear suspension and a new front brake, had subsequently been fitted to the production machine. The DBD34 also incorporated engine updates introduced by BSA’s chief designer Bert Hopwood. It featured a big Antal GP carburettor, ultra-close-ratio gearbox and peak output of 42bhp at 7000rpm.

                                            Other changes for the DBD34 Clubman's included the provision, for the first time, of the lights required by that season’s racing regulations. That gave the Gold Star a deceptively normal appearance, but there was no doubting its suitability for serious competition. This was a true racebike on the road: demanding, temperamental and - most of all - very fast indeed.

                                         The Gold Star tank badge dated back to the Brooklands Gold Star award won by BSA rider Wal Handley.

                                      Slim, uncluttered lines not only helped the BSA’s speed but made the bike look wonderfully purposeful too.

 Specification BSA DBD34 Gold Star Clubman                                         (1956)

Engine Air-cooled ohv two-valve pushrod single

Capacity 499cc (85 x 88mm)

Maximum power 42bhp @ 7000rpm

Transmission Four-speed, chain final drive

Frame Steel twin downtube

Suspension Telescopic front; twin shocks rear

Brakes Drum front and rear

Weight 384lb (174kg)

Top speed 110mph (177km/h)

BSA Road Rocket 650 (1956) Specification, Weight, Price

                           BSA Road Rocket 650

                                  The Road Rocket's handling might not have been outstanding, but the hard-accelerating twin went round corners well enough to be competitive with its twin-cylinder rivals.

                                        Slim styling in the BSA tradition gave the Road Rocket good looks to match its aggressive performance. The 646cc engine’s tuning parts ' included aluminium cylinder head, hot cam and high compression pistons.

                                         On its introduction in 1954, the 650cc Road Rocket was the fastest and best bike that BSA had ever built. More to the point, it was quick and stylish enough not only to become a hit in the big American market for which it had essentially been developed, but also to boost the image of the giant Birmingham factory, whose existing twin-cylinder 650, the A10 Golden Flash, was competent but not very exciting.

                                           The Road Rocket was a distinctly sportier machine than the Flash. As Motor Cycling magazine commented when the model was introduced to the home market in 1956, the Road Rocket was a roadgoing solo ‘with just that little bit extra in the way of speed and specification luxury . It was well suited to an American market that traditionally demanded style, capacity and performance from its motorcycles.

                                      In 1954, BSA was in the process of introducing a new twin-shock frame for the Golden Flash, as a replacement for the old design with plunger rear suspension. The Road Rocket used the new chassis to hold an engine based on that of the short-lived A10 Super Flash, BSA’s first sports 650cc model, which had been sold almost exclusively in the States the previous year.

                                                The 646cc parallel twin unit was tuned with an aluminium cylinder head, uprated exhaust valves, Arnal TT9 carburettor, hotter camshaft, toughened heavy-duty crankshaft, and high-compression pistons. It also had a manual advance-retard lever for adjusting the ignition, something that was not deemed necessary on the more softly tuned Golden Flash. Peak power rose to 40bhp at 6000rpm.

                                          Home market Road Rockets were fitted with flatter handlebars and more efficient silencers than the original export machines. They were otherwise identical to the American market bikes, complete with red paintwork plus the partially chromed fuel tanks that had become a BSA trademark.

Brisk acceleration

                                         Low-speed acceleration was very brisk, and despite its relatively high state of tune, the Road Rocket s twin-cylinder engine had plenty of low-down torque and a very docile nature. As The Motor Cycle magazine noted in its test of March 1957, the standard Golden Flash was well known for its wide spread of torque, but ‘the trait seems to have been enhanced rather than impaired on the tuned engine. In practice this means that really lusty acceleration and power reserve for gradients, head winds and passenger carrying are available over a broad engine-speed range.’

                                                More to the point, the Rocket was fast. BSA claimed a top speed of 105mph (169km/h), and the bike was timed at exactly that speed during one magazine’s testing, despite a cross-wind. Triumph s rival hot 650, the Tiger 110, was arguably faster still, but only by the slimmest of margins. Equally importantly, the Road Rocket could be cruised 'without signs of fatigue’ at between 95 and 1 OOmph (153-161km/h), according to one contemporary test.

                                            The Road Rocket’s speed and good looks, along with its dependable handling, earned it many admirers. Its motor proved impressively reliable, too. Its only mechanical weakness was in the area at the bottom of the cylinder block, which could give problems when the high-compression motor was revved hard.

                                              The Road Rocket sold well in the States but, after being introduced to the home market midway through 1956, two years late, it lasted in production barely more than a year before being replaced by the Super Rocket, which was a very similar bike but which had slightly higher compression ratio, redesigned cylinder head, Amal Monobloc carburettor, and a headlamp nacelle. The Road Rocket was no more, but it had succeeded in proving that BSA was capable of producing a fast and exciting 650cc twin.

                                               The Road Rocket name and tank logo helped to emphasize the BSA’s scorching performance. Not that this bike's rider needed much reminding, once the throttle was wound open...

                                            Chromed tank sides looked good when combined with the BSA’s red paintwork. The Road Rocket model’s mudguards were originally also chromed; this restored bike’s red finish was introduced with the Super Rocket in 1958.

                Specification BSA Road Rocket                                                    (1956)

• Engine Air-cooled ohv pushrod four-valve parallel twin
• Capacity 646cc (70 x 84mm)
• Maximum power 40bhp @ 6000rpm
• Transmission Four-speed, chain final drive
• Frame Steel twin downtube
• Suspension Telescopic front; twin shocks rear
• Brakes Drum front and rear
• Weight 4181b (190kg)
• Top speed 105mph (169km/h)