A tire layer application assembly and a method for applying a tire layer around a substantially circular circumferential surface of an object. The assembly is provided with a drive which, during application, is coupled to the object for driving the object in a driven rotation about a concentric axis of rotation with respect to the circumferential surface, wherein the assembly includes a tracking device which, during application, is arranged to be fixed to a part of the tire layer that is applied to the circumferential surface, wherein the tracking device is rotatable in a tracking rotation about the axis of rotation of the object, independent of the driven rotation of the object about the same axis of rotation.

It is ensured the strength of a welded section in a tire that is configured by welding tire constituent members formed of a thermoplastic material. A tire has a first welded portion, in which one section of one tire constituent member and one section of another tire constituent member are both melted and welded, and a second welded portion, which is formed by welding a welding-use thermoplastic material to the surface of the first welded portion, whereby the strength of the joint section is ensured.