What is an advantage of using a two-stroke engine?

A two-stroke engine is known for its higher power-to-weight ratio due to its ability to produce power with every revolution of the crankshaft, as opposed to a four-stroke engine that produces power every second revolution. This characteristic allows two-stroke engines to generate more power for a given engine size and weight, making them an effective choice in applications where weight and compactness are essential, such as in small boats, chainsaws, and dirt bikes.

This advantage is particularly valuable in situations where maximizing output while minimizing weight is critical. The higher power-to-weight ratio translates to better performance, allowing for quicker acceleration and response, which is why two-stroke engines are often favored in scenarios requiring agility and speed.

In contrast, the other choices highlight aspects that do not provide the same benefits. Lower fuel efficiency, complexity in design, and higher emissions are characteristics typically associated with two-stroke engines, making them less favorable in applications where environmental impact and operating costs are significant considerations.