The Rotary Engine Bike – A Blind Alley or Genius?

There have been a few development blind alleys for motorcycling over the years. One that immediately springs to mind being turbocharged engines. Others such as hub-centre steering still regularly crop up. Arguably even the brave shout by Kawasaki to develop the mighty supercharged H2R could fall into this category. I even find myself wondering if electric motorcycles will go the same way as e-fuels become more widely available.

A Blind Alley?

Another example of this phenomenon is the rotary engine. It has many advantages which perhaps explains why engineers remain fascinated with the layout and have returned to it many times over the years.

A rotary engine is light, has very few moving parts, runs very smoothly and can boast a great power output for a given swept capacity. This later point can depend on how you measure the chamber volume of a rotary. An argument around this has raged on and off in racing (& taxation!) circles for many years.

Several manufacturers of cars and motorcycles have toyed with the rotary engine. Some out of a desire to appear different from their contemporaries, but mainly I suspect out of pure engineering curiosity.

Not Just Bikes

In the world of four wheels NSU, Mazda and Citroen have been the principle protagonists. Mazda are still clinging to the raft, so to speak, right up to the present day. They manufacture a car with rotary/PHEV set-up. They might be making the answer to a question nobody is asking.

Several Have Tried

But in world of two wheeled madness DKW, Norton and Suzuki have been the leaders in an admittedly small field.  DKW came to market first with the pretty little DKW200. A simple looking roadster it enjoyed modest sales success in the 1970s.

DKW200 at the wonderful Sammy Miller Museum

Perhaps better known is the Suzuki RE-5. Looking a little like a peculiar GT750 ‘Kettle’ the RE-5 launched with a fuel crisis looming. The inherently conservative bike market of the 1970’s combined with massive increases in prices at the fuel pumps, killed the RE-5 before it had any significant foothold in the market. I have only seen examples in museums and bike shows which tells you what you need to know I suppose.

Suzuki RE5

The last bikes on the market with a rotary engine were of course offered by Norton. Emerging from the smouldering embers of the NVT group as it collapsed. The design was picked up a by then independent Norton set up. A small team working out of tiny factory in Staffordshire developed the engine to a point where it could be offered for sale in a bike.

Better Late Than Never

Nominally a 588cc air-cooled twin rotor the first model off the assembly line was dubbed the ‘Classic’. Despite the distinctly untraditional motor the bike was conventionally styled upright ‘roadster’. What would be called a retro-naked now. They quickly sold out the batch of 100 or so bikes. The few that reached the hands of the press were well received and continue to hold their value to this day. However this is another rotary bike that I have only seen in museums and the occasional show. Not surprisingly.

Norton Classic

Water cooled developments followed. These sold in moderate numbers to a number of UK Police forces around the mid 1980’s. My long suffering Dad even got pulled over by a bike cop riding example while giving me a lift home from clubbing in Brum. I encouraged him to take on a Jaguar XJ on the overpasses that led from the city centre. It was the only time he was ever ‘tugged’ by the plod. I still feel guilty about it to this day.

Fully faired and utilising Yamaha XJ900 cycle parts the Interpol was a success for Norton. There was even a smart civvy version dubbed the Commander.

The one my Dad got to see…The Norton Interpol II

But perhaps the two most famous rotary bikes were also products of this small outpost of the British bike industry. The RCW588 race bike debuted in 1987 and I remember all the fuss surrounding it when I went to watch it race at Snetterton at the time. By 1989 the programme was being sponsored by John Player and the bikes decked out in a stunning jet black and silver livery.

The 1987 Norton Race bike. I think the one I saw at Snetterton

Real Performance Showed Flashes of Promise

They were super quick, especially in a straight line. Ridden by the likes of Steve Spray and Trevor Nation they stormed past conventional bikes on the straight. This gave rise to some controversy regarding their equivalency with contemporary 750cc bikes like the OWO1 and RC30. I remember them tearing up the Rivett straight during the Snetterton ‘Race of Aces’ series. Leaving all comers in their wake. They won the British F1 series in 1989.

The legendary JPS Norton race bikes, now on display at The National Motorcycle Museum

They also raced on the Isle of Man and in the hands of Ron Haslam in Grand Prix.

To capitalise on this success a road bike with those JPS colours in a ‘race-replica’ package was offered to the public. Svelte and pretty the F1 was a cracking bike. I visited the factory with some friends in 1990 and saw them being built. Today they are, like all the rotary bikes, now almost exclusively the preserve of museums, shows and private collections.

The Norton F1

The revival was short-lived and despite some further developments by a former Norton engineer the Norton rotary is a footnote in biking history rather than a landmark. It was last seen in the late noughties and under the unfortunate ‘Garner-era’ Norton set up. Today the revitalised Norton makes bikes exclusively with conventional engines.

A Last Hurrah

This leaves us with no rotary bikes on sale today. With the rise of the electric vehicles, I doubt we ever will. Pity.

Words and Pictures: Tony Donnelly