Originally Posted by
rmac
Looking at these photos again, with a lot of vibration (since there is only one screw attached to the rack and one screw attached to the dropout) couldn't the part with the enlongated hole slip behind the rack? This would cause the rack to slip down and forward and perhaps interfere with the brake arm.
Anything is possible. However, nylon lock nuts tend to be very resistant to vibration.
That said, I'd already thought about this and have three mitigation strategies:
1. Add a small strut to join the upper mounting hole on the Fly rack to the bolt that attaches the rack to the frame triangulating the mounting bracket and rack.
2. Just fabricate a different mounting bracket to connect the rack to the frame that ties into both of the mounting holes on the Fly rack.
3. Stop screwing around with the Fly rack, get the Tubus Disco rack and combine it with the quick release mount.