Intake passage structure for internal combustion engine, and engine and vehicle incorporating same

摘要

An internal combustion engine includes an intake passage structure. The engine is configured such that a cylinder head is formed integrally with an intake manifold portion. A cylinder central axis is oriented parallel to an extending direction of an intake passage, when viewed in a side view. An injector is arranged such that it does not interfere with peripheral components, including the intake passage and a throttle body. The injector is disposed in the intake manifold portion such that a leading end thereof is oriented towards the intake valve of the cylinder head. The intake passage on the upstream side of an injector attachment position is offset from the injector in a width-direction of the internal combustion engine.