Originally Posted by
barturtle
Most Tubus Rack can be used with their QR Adapter set to mount to the skewer. The Fly and Luna would then mount to the brake bridge to complete the set up.
This would be the best bet. If you have a carbon post, the same issues apply as to clamping stuff to the frame.
Or, perhaps, it's time for another bike that will do the duty that you want it to do. Keep the Robaix for those light and fast rides but get something else for the epic rides and plodding to work.