Pulley device, in particular for tensioning idler or runner roller

A pulley device configured to support a belt of a chain tensioning idler or runner roller, comprising:

• a bearing having a rotatable outer ring and a coaxial fixed inner ring;
• and
• a pulley having at least one C-shaped pulley part, the at least one pulley part having an inner portion with an inner surface mounted on an outer cylindrical surface of the bearing outer ring, an outer cylindrical portion having an outer cylindrical surface configured to contact the belt or the chain, and a radial intermediate portion extending substantially radially between an axial outer end of the inner cylindrical portion and an axial outer end of the outer cylindrical portion, each of the at least one pulley part being formed integral and defining an open end on an axial side opposite the intermediate portion;
• wherein a ratio between a material thickness of the outer cylindrical portion at a first location radially outward of the outer ring and a material thickness of the inner cylindrical portion at a second location radially between the first location and the outer ring is strictly greater than 1.