As the Universal Japanese Motorcycle became all the rage, British manufacturers knew they had to do something radical to stay in the game. Some, like Hesketh, started with a clean slate. Others, like Norton, started to think outside the box. David Garside thought of triangles, specifically the rotors inside the Wankel rotary engine.

This was not the first appearance of a Wankel in a motorcycle. Its simple design and compact size seem to make it ideally suited for motorcycle use, or so Suzuki thought when it made the RE5 in the 1970s. In April 1985, it made Cycle World's list of the ten worst motorcycles ever. They said the RE5 "managed to combine the cost of a superbike, the mechanical simplicity of a 747, the sound of an out-of-tune B-29, the performance of a fair-to-middling 350, and the aesthetic appeal of a high-speed train wreck, all into one highly unsalable motorcycle."

That's hardly something Norton would want to emulate. Designer David Garside saw hope in the Wankel, though, because he had seen a Hercules use one more effectively than Suzuki. He designed an engine with two rotors, not one like the RE5, to double its capacity. The way a Wankel works, each rotor acts basically like three cylinders, with three chambers at different parts of the combustion cycle as the rotor turns. Two rotors essentially made the equivalent of a 588 cc six-cylinder motorcycle.

 

Of course, there are other disadvantages to rotary engines. Their small size means they are terrible heat sinks, and overheating is a major concern. For that reason, Norton's first rotary bike, the Interpol 2, was sold only to civilian and military police forces. They had an intense maintenance schedule and required their riders to pay close attention to the temperature gauge and respect it. In 1988, though, Norton made this engine available to civilians in the Classic. Only 100 would be made, and they sold out extremely quickly, mainly to collectors.

This particular example is number 91, sold to its original owner on August 1, 1988. It has just 4,200 miles on it, indicating that it has spent its life as a collectible, not actually being used. It was last on the road around 2005, though it had some work done over the last few years, including stripping and cleaning the entire fuel system. It will require more work before it's roadworthy again. If you're up for the challenge, or just want to own a super rare collectible Norton, it will up for auction through Bonhams on December 12, 2020.