68 :OLD BIKE AUSTRALASIA
bikes astounded the motorcycle fraternity, Bill Smith’s
race time was 1 hour 16 minutes 38.2 seconds
(averaging 88.63mph / 142.64kph), with Tommy
Robb just 0.4 seconds slower: fast enough for them to
place third and fourth in the 500cc Production race
and sixth and seventh in the 750cc Production race!
Bill Smith’s lap record stood until 1974 when it was
finally beaten by resurfacing of the track, modern
race tyres and new engine technology. Tommy’s bike
also came fourth in the 1968 250cc Production TT,
ridden by Brian Richards who bought the bike
through Bill Smith after the 1967 TT and who sold the
bike to Kenny Lucas in 1980s.
The Bultaco’s TT win was very controversial, many
thought that they were “cheating” using special
factory bikes equipped with un-muffled expansion
chambers. However, all the race kit parts were listed
as optional extras in the standard road bike parts
catalogue so they were legal – even the incredibly
loud expansion chamber! In those days there were
no noise limits on road/race bikes, in fact there was
no way of accurately measuring the sound level. The
race rules at TT Production bikes stated that “bikes
had to be fitted with an efficient exhaust system”,
and there is nothing more efficient than an
expansion chamber! The racing kit was summed up
in a factory brochure: “the kit can be easily installed
by the customer himself, all that is required is a set
of spanners, a medium cut file, a drilling machine,
three drills and a dose of enthusiasm”. It cost about
half the price of a standard new Metralla and
consisted of a special fibreglass race tank with
mounting brackets, a steel 2-piece adjustable
hump-backed single seat, a silver bikini fairing, clip-
ons, rear-sets, rear brake switch mount, ported
barrel (same as the Pursang Mk2 moto-crosser),
11:1 or 12:1 high compression head, modified
piston, a close ratio gearbox, assorted drive
sprockets, expansion chamber, carburettor
bellmouth and jets, cables, a FEMSA electronic
ignition system and even a racing spark plug.
Complete race-kitted bikes could also be purchased
directly from the various Bultaco dealers.
This bike was meant to be raced, so I have set
about fixing it up to race in the Australian Post-Classic
scene to see how well it goes, before retiring it. The
bike is a little different to when it raced in 1967 due
to race damage, wear and tear etc. over the following
20 years but the main parts of it are still original. I
fitted a larger 36mm Amal Mk2 concentric carb in
place of the 34mm Amal Mk1 that came with the
bike which have a bad reputation for breaking slides
and destroying pistons. There is also a lot of
information around re jetting the 36mm Mk2, which I
decided to run on 100 octane petrol rather than
alcohol, with synthetic racing oil at 25:1. The gearing
and ignition were checked, starting was hard, first
gear seemed very high but once under way the bike
seemed to run O.K. A very firm front suspension was
traced to the right hand fork leg sticking on thestanchion, but a replacement fork leg fixed this. The
front brake backing plate was also replaced due to a
very loose brake shoe pivot pin and the brake pads
radius ground to match the iron liner. The front wheel
rim had also been laced up with an incorrect offset,
resulting in the wheel being off centre.
A faulty top coil stopped proceedings at our first
race meeting at Sydney’s Eastern Creek in February- The next race meeting was at Sydney’s Oran
Park in April 2002 which was a bit more successful
than the one at Eastern Creek, at least it started
BULTACO METRALLA MK2 TT
The Metralla duo at the 2017 Debenham Rally in the NSW
Southern Highlands. John Somerville’s well-travelled model
(left) and Andrew Flowers’ race-kitted version.
Factory race kit
components.