A module, usable with a plurality of other modules, to obtain an annular modular assembly adapted to fill a tire of a cycle or motorcycle. The module can be removably inserted into the tire and includes a body made of foamed elastomeric material defining a portion of the annular modular assembly. The body has a shape of circular or ellipsoidal section with tapered end areas designed, in use, to remain facing or in contact with one of the tapered end areas of the adjacent modules. The tapered end areas define respective planes converging toward the center of the tire and angularly spaced by an angle between 8? and 30?.