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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 HOmph
(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 lOOmph (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 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 Amal 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.
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 ~f~ Steel twin downtube
Suspension Telescopic front; twin shocks rear
Brakes _j-Drum front and rear
Weight 384lb (174kg)
Top speed 110mph (177km/h)
Source Fast Bikes Robert Brown
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