Cyril Halliburn hatched the idea of taking the B.50 motocross engine and turning it into a speedway engine.
It is difficult today to imagine just how big a company BSA was at its peak. At one time, in the mid-1960s, the BSA group was the tenth-largest company in Britain and had all the arrogance of the undisputed king of the jungle. However, by 1973, BSA was in deep, deep trouble and things were happening at the factory that would have been unthinkable even two years before. It had always been BSA policy not to sell engines to anyone outside the company, but in its dying days every potential source of income was being hunted down.
One of the ideas hatched in the last-chance saloon was to manufacture both a complete BSA speedway bike, ready to race, and also to sell engines to riders. The BSA competition shop had been closed the year before, as part of cost-saving measures, but there was still race development of sorts taking place at BSA's Small Heath factory. This was carried out by Cyril Halliburn, a dignified, archetypal Midlands engineer who was in charge of Quality Control at BSA. In his younger days, Cyril was known as "Mr. Gold Star" for his knowledge in tuning the renowned BSA singles and he was a keen racing enthusiast.
Cyril hatched the idea of taking the B.50 motocross engine and turning it into a speedway engine. From BSA management's point of view, it had the dual benefits of being an extremely cheap project and one that might well have generated some income very quickly.
The concept looked to be quite practical too. The very best B.50 motocross engines were giving around 39bhp whilst the B.50 road racer ridden by Bob Heath was up to nearly 45bhp - both running on 5 star (101 octane) pump petrol.
Jawa speedway engines, which were the standard equipment at the time for professional racers, produced around 50bhp on methanol. Since methanol offered around 25% increase in power over petrol, on paper, it looked as if the BSA would be a sound proposition.
The idea was that slightly modified B.50 castings would be used for the cylinder barrel, head and rocker box, and standard B.50 internals would also be employed. Cyril quickly developed a cam for the engine and only the crankcases were new since speedway engines had no need of a conventional gearbox and clutch.
The BSA made a wonderful noise and provided the thrill that only an alcohol burning speedway bike can provide.
The theory was fine but inevitably, BSA management had no grasp of the practical requirements needed to make the project a financial success. First, Cyril had virtually no funds to develop the BSA engine and, on the track, it proved to be much slower than the Jawa. In testing, even fanatically patriotic British speedway riders scorned the BSA and refused to use it for actual racing.
Then there was the fact that the Jawa was designed for competition use - and more particularly, the almost nightly grind of the professional speedway rider. By contrast, the BSA speedway engine was converted from a road engine which was fragile even when lightly used.
Finally, BSA wanted to make a batch of 1000 engines, dump them on the market and withdraw. This was not the attitude which was going to succeed in racing where professional riders demanded commitment from suppliers.
The BSA made a wonderful noise and provided the thrill that only an alcohol burning speedway bike can provide. But so did the Jawa - and more so. Grasping at straws rarely works - as BSA proved in the case of this desperate attempt to raise money.
Contact BSA Owners Club www.bsaoc.demon.co.uk
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