Upper structure of engine

摘要

Disclosed is an upper structure of an engine having three or more cylinders arranged in a row. A first one of a pair of adjacent cylinders among at least three of the cylinders serially arranged in a cylinder row direction is provided with a second spark plug at a position on an opposite side of a second one of the pair of adjacent cylinders, and the second one of the pair of adjacent cylinders is provided with a second spark plug at a position on an opposite side of the first one of the pair of adjacent cylinders. The present invention can provide enhanced flexibility in design of a head cover of the engine.