Originally Posted by
denis_987
My rear rack is the one that came with my Ghost Square hybrid bike. I can load upto 25 kg max (written on the rack). So far, with my 40 liters panniers, I load about 10 kg.
I think I can easily use the 70 liters panniers and a rack pack to acheive 25 kg. I weighed my full packed trailer and it weighs 22 kg at 100 liters capacity (minus the weight of the trailer).
The 31 liter Rack Pack and 70 liters of panniers would be 101 liters. Djb showed his 31 liter Rack Pack above, mine in the photo below. I have the standard Backrollers at 40 liters, rack is a Tubus Logo EVO rated at 40 kg. (Tubus dropped the rating to 26 kg after I bought it.)
I recently learned I was doing this wrong, I was only clipping two of the four straps. More here:
I put a sheet of Coroplast in my Rack Pack to give it more structure, that holds it in a shape more like a cylinder instead of a wet pillowcase. I first tried cardboard, that worked well enough that I decided to buy some Coroplast at home despot for a permanent addition. I put lots of parallel creases in the Coroplast about 2 inches apart from each other so that is in the bottom and rolls up the sides of the bag.
If you get one, the Rack Pack sits on the panniers, not the rack. I usually still use a strap around the Rack Pack and the rack (black in the photo).
I also found that the 31 liter Rack Pack is a perfect size for airline carry on bags with most airlines. This was my luggage for one of my trips, I wore the helmet onto the plane so that the baggage handlers did not have a chance to crack it.
I have also used that Rack Pack as a carry on bag on trips where I was not biking, it was a handy thing to have.