The engine has two groups of cylinders i.e. V-motors, that are arranged at a mutual angle greater than zero. An inlet system (1) has a header pipe (4) that flows into inlet manifolds (2). Each cylinder is connected to one of the inlet manifold that is comm...

An improved design of inlet manifold for an IC engine has the ducts in pairs, positioned over each other with a separating wall. The ducts are made from half shell pressings with interlocking flanges and connect a plenum chamber with the separate cylinders...

The invention securely reduces an intake resistance in a high speed rotational range and thereby to contrive enhancement of a high speed output performance, while securing a low speed output performance of a parallel multi-cylinder engine for a motorcycle....