Patent ID: 7424938

Claim:
A bicycle disc brake rotor for a bicycle disc brake device, the bicycle disc brake rotor comprising: a rotor member including a first ring-shaped member and a pair of second ring-shaped members disposed on opposite sides of the first ring-shaped member, the second ring shaped members including a material with higher wear resistance than the first ring-shaped member, the second ring shaped members defining brake pad engaging friction surfaces of the rotor member on exposed sides thereof, the first ring-shaped member having a first thickness measured in an axial direction relative to the rotor member in the region adjacent to the brake pad engaging friction surfaces and the pair of second ring-shaped members each having a second thickness measured in the axial direction in the region of the brake pad engaging friction surfaces, at least one fixing hole being formed through the first ring-shaped member and the second ring-shaped members with at least one depression formed in the surface of the rotor member such that the first ring-shaped member has a reduced thickness less than the first thickness in an area corresponding to the depression around the fixing hole and each of the second ring-shaped members has a thickness in the area corresponding to the depression around the fixing hole that is approximately the same as the second thickness; and at least one fastening member mounted through the at least one fixing hole of the first ring-shaped member and the pair of second ring shaped members of the rotor member, the fastening member is configured and arranged to fixedly attach the rotor member to a hub mounting member.