Rotary engines, also known as Wankel engines, have some of the most rabid and loyal followings of lovabale nutjobs of any pretty-much-failed technology. I think rotaries are fantastic, but, let’s be honest, they never lived up to their hype. Once, though, long ago, the world was a different place, and if you truly loved the Wankel motor, you could have used one to mow your lawn.
Rotaries first came to market via German carmaker NSU, but it was Mazda that proved to be the most determined adherents of rotary engines. Fuel economy and reliability were always issues that rotaries struggled with, and most manufacturers didn’t find them to be worth the trouble.
That’s why it’s so amazing that the Arctic Cat company in the early 1970s decided that a rotary engine would be a great choice for a lawnmower. They sourced an engine from the OG Wankel-welders, NSU, which made a respectable four horsepower.
Really, at the time, a rotary mower probably seemed like a fantastic idea; rotaries make good power for their weight and size, and have many fewer moving parts than a normal reciprocating-piston engine.
Rotaries are such rarities now, with Mazda making the last new car with one back in 2012, that seeing one in use for something as pedestrian as a lawnmower feels absolutely mad, a relic from some alternate reality that never quite happened.
Interestingly, the mower runs on a mix of gasoline and motor oil, like a two-stroke motor, though a Wankel already isn’t exactly a four-stroke motor as it is; it’s basically an Otto-cycle four-stroke-type engine, but fuel gets into the combustion chamber in a way that’s more like a two-stroke, so it’s just sort of confusing.
Anyway, if you’re a hardcore NSU Ro80 or Mazda RX7 owner, you owe it to yourself to find one of these metal-Dorito-powered lawn machines.
DISCUSSION
I put Wankels, jets, rockets, and atomic power plants in the same category: Interesting and useful in their own right, but hopeless for emissions (in-use and potential), and wildly inappropriate for the modern car.
Diesels are kind of in that category as well, but huge research and spending into emissions control has kept the damn thing alive long after Rudolf said aufwiedersehen, bitches! and jumped into the ocean.