Four-stroke engine

A four-stroke engine is an engine in which four strokes (intake, compression, combustion, and exhaust), in other words one cycle, are completed while the piston makes two reciprocations.
Mainly has the following features.
(1) Low fuel consumption: Loses less fuel and consumes less fuel than a two-stroke engine.
(2) Stable operation at low speed: Since there are no breaks in combustion due to incomplete exhaust as in a two-stroke engine, operation is smooth at low speeds.
(3) Ideal balance: Since the work of each stroke is divided precisely and ideally, components are less likely to overheat.
(4) Noisy: Due to complexity of the valve mechanism and the large number of parts, tends to produce significant mechanical noise.
(5) Suited to multiple cylinders: Because there are a low number of combustions, the number of cylinders has to be increased to ensure smooth operation.

Today, four-stroke engines are mainstream worldwide, and the use of two-stroke cycle engines is declining.