An article made by composite material, comprising a body made of reinforced fiber and having at least two opposing sidewalls; and two foam components embeddedly disposed in the sidewalls of the body, respectively; wherein the body is a rim; wherein the body further has an outer circumferential wall and an inner circumferential wall, with the outer circumferential wall connected between the two sidewalls and separated from top ends of the two sidewalls by a predetermined distance, and the inner circumferential wall connecting bottom ends of the two sidewalls; wherein thickness of top and bottom ends of the foam components is less than thickness of central parts of the foam components; wherein each of the sidewalls includes an outer sidewall portion and an inner sidewall portion; wherein each of the sidewalls is connected to the outer circumferential wall by an end of the outer sidewall portion thereof; wherein each of the inner sidewall portions is connected to an inner side of one of the outer sidewall portions and spaced from the outer circumferential wall at a predetermined distance; wherein each of the foam components is embeddedly disposed between the outer sidewall portion and the inner sidewall portion of each of the sidewalls; wherein the outer sidewall portion, an inner sidewall portion, the inner circumferential wall, and the outer circumferential wall collectively encompass a hollow portion without being filled with any fill material; wherein the body further comprises two lips, each of which is connected to one of the two ends of the outer circumferential wall, characterised in that the outer sidewall portions of the sidewalls are outwardly protruded away from each other to both have an arched convex shape, and the inner sidewall portions of the sidewalls are inwardly protruded toward to each other to both have an arched concave shape. a body made of reinforced fiber and having at least two opposing sidewalls; and two foam components embeddedly disposed in the sidewalls of the body, respectively; wherein the body is a rim; wherein the body further has an outer circumferential wall and an inner circumferential wall, with the outer circumferential wall connected between the two sidewalls and separated from top ends of the two sidewalls by a predetermined distance, and the inner circumferential wall connecting bottom ends of the two sidewalls; wherein thickness of top and bottom ends of the foam components is less than thickness of central parts of the foam components; wherein each of the sidewalls includes an outer sidewall portion and an inner sidewall portion; wherein each of the sidewalls is connected to the outer circumferential wall by an end of the outer sidewall portion thereof; wherein each of the inner sidewall portions is connected to an inner side of one of the outer sidewall portions and spaced from the outer circumferential wall at a predetermined distance; wherein each of the foam components is embeddedly disposed between the outer sidewall portion and the inner sidewall portion of each of the sidewalls; wherein the outer sidewall portion, an inner sidewall portion, the inner circumferential wall, and the outer circumferential wall collectively encompass a hollow portion without being filled with any fill material; wherein the body further comprises two lips, each of which is connected to one of the two ends of the outer circumferential wall, characterised in that the outer sidewall portions of the sidewalls are outwardly protruded away from each other to both have an arched convex shape, and the inner sidewall portions of the sidewalls are inwardly protruded toward to each other to both have an arched concave shape.