Brake pads from new dual pivot calipers dont reach the rim in the rear wheel I bought a bike exactly like this one some time ago (bonvelo, a small company here in germany):


I wasn't really happy with the brakes so I decided to search for a good used ones. I found a good offer for the shimano 7800 BR and bought them.

I installed the front one without problems but the rear one is being a nightmare.

The problem: When I try to install the shimano brakes one pad reaches perfectly the rim but the other one (opposite side than the cable) does not reach the rim and collides with the rubber of the tire.

I can't find which model of brakes did the bike had, I can only see the brand written and it says promax.  Here are some photos of the two brakes:



I can't see what is wrong with the new ones, that doesn't allow the right side to reach the rim, because the height of both seems to be the same. The width of the tyre (28) should not be the problem as the front one works perfectly There is a washer that was in the old brakes but does't make any difference for this problem if I put it or not.

To show better the problem. This is the bridge:


This is the probem where the brake pad collides with the tire:


And here the brake pad reaches the rim if I have a little angle between the bridge and the brake, but I can tighten the brake in that position:
 

Is there anything I can do to install this brakes in this bike?
What you really need is brakes with longer reach. Reach is the measurement from mounting hole to rim, you can measure it with a measurement tape and it is listed for most of rim brakes.

If you absolutely want to install these brakes no matter the cost or reliability, there exists a component called drop bolt. These used to be more common in days of classic steel frames and single pivot brakes, but NOS parts are still available. I would recommend disassembling your brake and verifying its mounting bolt is compatible before buying anything.