What type of motor is characterized as a "two-cycle" engine?

A two-cycle engine, more commonly known as a two-stroke engine, is characterized by completing a power cycle in just two strokes of the piston, which means it fires once every revolution of the crankshaft. This design allows for a simpler construction, fewer moving parts, and a lighter weight compared to a four-stroke engine.

In a two-stroke system, each cycle includes both the intake and exhaust processes occurring simultaneously. The engine operates by having the fuel and oil mix inject at the same time, which is essential for lubrication as well. These engines are typically more powerful for their size because they produce power with every revolution, making them popular in applications like outboard motors for boats.

Other options, such as single-stroke outboard motors and four-stroke engines, do not operate under the same two-cycle principle. The hybrid motor combines different types of engines, typically to reduce emissions and improve fuel efficiency rather than fitting the two-cycle classification. Therefore, two-stroke engines are uniquely defined by their method of operation, making them distinct and effective in certain powerboating scenarios.