Rotary has gone automatic
By JAMES A. GROTH
Copley News Service

Around and around we go on the rotary front. First off, Mazda, the first car to put the Wankle rotary engine in a production automobile is now offering automatic transmission.

Although it doesn't have quite the same oomph starting from a dead stop as its manual brother, the Mazda automatic doesn't lose all that much power. In tests the automatic went from 0 to 60 only three-tenths of a second slower than the stick. It was only five-tenths slower in the quarter mile.

Gas mileage has been none too spectacular in the new automatic but then gas mileage has never been one of the rotary engine's strong points.

IN A COUPLE of Tokyo auto shows two new rotary engines were introduced -- one for a car and another for a motorcycle. Both should be on the market soon.

Nissan Motor Co. which makes Datsun will be the next auto maker to put the rotary into production. Although there are some differences the Datsun rotary is essentially the same as the Mazda using two rotor, a four-barrel carburetor, twin ignition and water colling. Where the two engines differ is that the Datsun has a peripheral port type while the Mazda is a side-intake port type. Each of the Datsun rotor housing is 500cc, slightly smaller than Mazda but Nissan is planning on surpassing Mazda's 130 horsepower rating (before the smog goodies go on).

The engine is being supplied by Toyo Kogyo (Mazda) for the Datsun.

Mazda has helped the problem of low-end torque by taking advantage of the car's wide range of r.p.m. The automatic is set to shift at 6,000 r.p.m. when the gas pedal is on the floor.

BUT DATSUN HAS a head start on Mazda. The company already has a well-organized distribution system in the United States with dealerships well-established. Mazda on the other hand had to start from scratch.

It looks as though Yamaha will be the first company out with a rotary motorcyle. The company displayed a 660cc 68-horsepower 6,000 r.p.m. model at the Tokyo motor show recently.

The engine is made by Yamaha Diesel, a Yamaha subsidiary which has been making rotary outboard engines for quite a while.

The Yamaha rotary look a little like a trimmed-down Mazda with its twin rotors and water cooling system.

If things work out the way Yamaha expects, the rotary bike could be King of the Road almost immediately. It will certainly be the smoothest riding of the touring bikes (almost vibrationless) and one of the quietest because of the water-cooling system.