Internal combustion engine

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 common to the cylinders, via inlet tracts (6, 8). The inlet tracts include inlets (7, 9) facing the inlet manifolds. A flow path for each inlet tract is common within the inlet manifolds between an opening (5) of the header pipe and the inlets. Independent claims are also included for the following: (1) an operating device for an inlet thread of an internal combustion engine (2) a method for operating an internal combustion engine.