I'm working on a 2024 Dolan Ares road bike. I need to upgrade the rear brake disc from 140mm to 160mm. There only seems to be one style of flat mount rear caliper spaces to go from 140mm to 160mm and it does not even come close to mounting the caliper in the proper position.

With the 160mm rotor on the wheel and the wheel mounted on the bike and the caliper sitting where it would need to be mounted, the caliper is sitting just over 11mm above the face of the original mounting surface on the frame, and the bolt holes in the caliper are sitting roughly 3.5mm forward of the bolt holes in the frame.

Does anyone have any suggestions for a solution?


Mount Spacer

Roughly where caliper needs to sit