[Grant-53]

The key to any project is to analyze the cost versus benefit ratio. The question a builder must ask is whether this an art project or an engineering exercise. A three cylinder 1.0L engine is usable on a large motorcycle. There is an optimal power to weight ratio for a car or motorcycle in the range of 36 lb GVW per horsepower. Polaris is using a 2.4L car engine in its trike.
The Curtiss-Wright rotary engines were licensed from Sachs. Singe rotor air cooled versions were used in snowmobiles. Larger multi rotor designs were developed for aircraft. C-W did work on stratified charge induction to improve fuel efficiency. Mazda uses side ports for their car engines. Some industrial rotary engines are being developed. For rotary engine motor vehicle manufacturers specialized tooling and emissions testing are required. Price vs volume competition can be fierce.