Brake disc for bicycles

[0020]With reference to FIGS. 1 and 2, a brake disk for bicycles in accordance with the present invention comprises an inner disk 10, two outer disks 20 and multiple brake units 30.

[0021]With reference to FIGS. 2 to 4, the inner disk 10 has multiple inner fastening holes 11. The inner fastening holes 11 are formed through and are annularly arranged separately on the inner disk 10.

[0022]The outer disks 20 are respectively mounted on two sides of the inner disk 10 and clamp the inner disk 10, and each outer disk 20 has multiple outer fastening holes 21. The outer fastening holes 21 are formed through and are annularly arranged separately on the outer disk 20.

[0023]In a preferred embodiment, the inner disk 10 is made of carbon fiber, glass fiber, or engineering plastic, and the outer disks 20 are made of carbon fiber, glass fiber, or engineering plastic. The outer disks 20 and the inner disk 10 are glued to each other.

[0024]The brake units 30 are mounted in the inner disk 10 and the outer