For a brief period in the 1970s, one of the most powerful race bikes in the world was being built in a converted chapel in North Wales.
Sparton was a collaboration between Barton Engineering and Spondon Engineering. Barton brought the two-stroke engine expertise, Spondon brought the frame-building brilliance, and together they created a machine that gave privateers serious firepower against the factory giants.
At the heart of the story was Barry Hart, who built racing two-stroke engines at Barton Engineering. In 1974, he joined forces with the noted frame builder Spondon to create a race bike with a 500cc square-four engine based on the Suzuki RG500.
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The project quickly attracted attention. Rex White of Suzuki Great Britain was sufficiently impressed to ask Barton Engineering to develop a 350cc Suzuki for Barry Sheene.
Barton then turned a Suzuki GT380 into a water-cooled engine, although still using the original crank and crankcases. The result was a very fast machine, but the project came to nothing. The official story is that Suzuki Japan caught wind of what was going on and closed it down, although it may simply have been that the machine needed a lot more development and refinement.
Barton continued work on its three-cylinder engine, making it much lighter, but eventually sold it in order to concentrate on building a 500cc motor.
The first version had a 458cc displacement, which evolved into a 525cc motor using Yamaha pistons and producing 100bhp.
At the 1975 Isle of Man TT, the world sat up and took notice when a Sparton 500, ridden by Martin Sharpe, was recorded at 146mph. This was at a time when factory teams such as Kawasaki were performing little better despite having massive resources behind them — and certainly considerably more funding and workforce than Sparton.
In 1976, Spartons took the top two positions at the North West 200, ridden by Martin Sharpe and Frank Kennedy respectively.
Development continued with a 497cc version of the engine, purportedly capable of 160mph. Sparton built several machines for privateers, most notably for Graham Wood, who took a dozen wins in 1977 on his Sparton.
A 750cc square-four called the Phoenix was also launched, but there were reliability problems. Sparton stated that it wanted to sell engines to riders who “are prepared to work with us to solve any problems that may occur”.
In other words, it wanted its own customers to act as guinea pigs, and only a handful of Phoenix engines were made.
Considering their limited numbers, Spartons were remarkably successful on the race track, but the company eventually came to an end in 1982. It was unable to compete with the huge funding that the big four Japanese factories were prepared to pour into research and development.
Barton was eventually sold to Armstrong and then to Erik Buell, although Buell would later choose to pursue other ideas.
You may think you’ve never seen a Sparton, but we would wager you have — that is, if you have ever seen the film Silver Dream Racer, starring 1970s heartthrob David Essex.
In the film, Essex plays Nick Fletcher, who campaigns an experimental motorcycle built by his late brother. If you’ve never seen the movie, we won’t spoil the ending, but you can probably guess.
Barton made three machines for the movie, although only two were ever used on screen.
