I plan to take my DSLR on my next tour. I'm not sure what type of gear setup you use for carrying other gear, which might make this suggestion seem useless. I pull a trailer when on a tour, with a handlebar bag. For scooting around town with the DSLR I used the Topeak Dynapack. The camera fits inside it well, and is long enough for my 18-200 zoom. There is enough room for the camera, and a bit of padding, perhaps my rain cover and remote for the camera.

http://www.amazon.com/Topeak-DynaPac.../dp/B000ZKCL4I

If you are interested, I can post pics of the Dynapack with my Canon T1i in it when I have more time later.