Abstract: A bicycle chain cover includes a rear casing, an outer cover connected with the rear casing, and an inner cover connected with the rear casing. The inner cover and the outer cover are opposite to each other. The inner cover has two first ribs, two second ribs, a first ring and a second ring. The two first ribs are disposed at an inner edge of the inner cover. The two second ribs are disposed at the inner edge of the inner cover. The first ring is connected to the two first ribs. The second ring is connected to the two second ribs. The second ring is rotatably disposed in the first ring.

Abstract: A bicycle light assembly includes a light shell, a light holder, a light device and a positioning element. The light shell surrounds tubes of a bicycle frame. The light shell has a locating space penetrating through the light shell in a front-to-rear direction, and an opening communicated with the locating space. The light holder is covered to a front of the opening. The light device is connected to the light holder. The light device is positioned in the locating space. The positioning element is positioned in the locating space. The positioning element has a main body. The main body is sleeved on an outer surface of the light device. The main body has a first positioning piece and a second positioning piece. The first positioning piece abuts against an inner surface of the light shell. The second positioning piece abuts against a rear surface of the light holder.