Stroke ratio

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Stroke ratio" – news · newspapers · books · scholar · JSTOR (August 2009) (Learn how and when to remove this message)

Stroke ratio, today universally defined as bore/stroke ratio, is a term to describe the ratio between cylinder bore diameter and piston stroke length in a reciprocating piston engine. This can be used for either an internal combustion engine, where the fuel is burned within the cylinders of the engine, or external combustion engine, such as a steam engine, where the combustion of the fuel takes place outside the working cylinders of the engine.