tvåtaktscykel

Two-stroke engine motorcycle, commonly referred to as "tvåtaktscykel" in Swedish, is a type of motorcycle powered by a two-stroke engine. This design contrasts with four-stroke engines, which are more common in modern motorcycles. Two-stroke engines have a simpler design, consisting of a single piston that completes a power cycle with two strokes of the crankshaft per cycle.

The operation of a two-stroke engine involves the mixing of fuel and air in the crankcase, which is then drawn into the cylinder by the downward stroke of the piston. Combustion occurs as the piston moves up, and the exhaust and fresh mixture are expelled during the same stroke. This design results in a simpler engine with fewer moving parts, making it lighter and more compact.

Two-stroke engines were popular in the early days of motorcycling due to their simplicity and efficiency. However, they have largely been replaced by four-stroke engines in modern motorcycles due to stricter emissions regulations and the need for more power and torque. Despite this, two-stroke engines are still used in certain applications, such as small engines for lawnmowers and chainsaws, and in some high-performance motorcycles.

The sound of a two-stroke engine is distinctive, with a characteristic "thud" or "thump" sound produced by the combustion process. This sound is often associated with classic motorcycles and has become an iconic feature of two-stroke engine motorcycles. However, the use of two-stroke engines has declined in recent years due to environmental concerns and stricter emissions regulations.