A burner incorporating a pilot cone and a mounting insert is provided. The pilot cone is constructed as a pilot cone assembly which is decoupled from the mounting insert. Further, an operating method for increasing the service life of a burner which incorporates a pilot cone assembly and a mounting insert is provided. The pilot cone assembly has a cone side and incorporates at least one further side where the further side is arranged to be essentially parallel to one of the sides of the mounting insert and spaced apart from it, so that between the further side and the side of the mounting insert there is a defined gap. In an operation of the burner, the gap is significantly reduced by the thermal expansion in at least at one point of contact between the further side and the side of the mounting insert. Finally, an assembly method is provided.