The Norton Rotary Engine

When Norton announced in December of 1987 that the company was going to produce 100 motorcycles powered by its air-cooled rotary engine, they were all spoken and paid for up front within a few weeks.

Quite astounding really, except these buyers were mainly savvy collectors, knowing that their purchase would surely increase in value. If the number had been 10,000, which is what the Norton would have had to sell in order to expect reasonable profit, maybe the results would have been different.

The story of the Norton Rotary engine is a pretty messy one, one of misdirection and missed opportunities. It began back in 1969 when BSA/Triumph hired an engineer named David Garside because he had worked on a rotary-engine project with the Rolls Royce company. For those unclear on the concept, rotary engines make power by one or more rotors rotating, as opposed to reciprocating engines which have pistons going up and down. The rotary has the advantage of fewer moving parts than any four-stroke engine, but is way more complicated. It is also thirsty, and offers no compression braking.

As we would say in Thailand or China, 1969 was not a stellar year to have been hired by the British motorcycle industry, which was going into an irrevocable tailspin, but Garside went to work on the idea of a small rotry that would fit into a 250 chassis. In 1973 the remnants of the once-great industry was lumped into one large group, Norton/Villiers/Triumph, headed by an astute businessman, Dennis Poore. He realized that the old pushrod, kickstart engines were fast approaching extinction, but he had no real money for research and development. The best Poore could do under the circumstances was to develop the rubber-mounted Commando, but with this fellow Garside on staff he felt that the opportunity for a completely different engine was in the future.

Poore was not alone. Germany's DKW was the first to test a Rotary engine with the short lived 1974, 297cc Hercules W2000 – the W to honer Fritz Wankel, who did crucial development on the rotary in the 1950s. Suzuki had the 497cc RE5 ready to go late in 1974, but it bombed financially. Yamaha's management took note and sensibly pulled its rotary RZ201 out of production after showing a prototype in 1975. Even with this rather dismal beginning, Norton persevered.

In 1975 NVT had to make a financial decision: Build an enlarged 870cc pushrod Trident, or develop the rotary. Poore thought that the rotary, when/if perfected, would have far greater sales potential in the future, and by 1977 the company – which had moved to the English Midlands town of Shenstone – had a working 588cc twin-rotor engine. This was put to hard testing, and a police-only Interpol II model was being sold to British forces in the early 1980s. It seemed to be a go, and by 1983 the marketing types were advocating the promotion of the rotary with a loud and colorful introduction of a civilian version.

However, Poore, an engineer, was concerned that the air-cooled engine would not stand up to consumer abuse, and told his people to start working on a liquid-cooled version. Four more years went by and Poore, now dying of cancer, sold the remnants of Norton company to Phillipe LeRoux, a man more interested in profit than reputation. LeRoux quickly announced that 100 motorcycles using the air-cooled rotary would go on sale.

Basically this was also the end for the Norton Rotary engine, less than 800 Norton rotaries, from the Norton Interpol II to the Norton F1 Sport, were ever sold.