Profpointy
Legendary Member
http://dawescycles.com/product/canvas-saddle-bag/ lists it as 190mm width and gives no volume. Comparing it to other bags in the range which give sizes as 15l and 20l, I'd say that 5 litres would be optimistic.
Carradice Super C SQR?
But my solution is ye olde stylee cheap haversack with two long QR compression straps through the saddle loops/rails which get tightened to pull the bag up snug. 20 litres. I'll let you know how it goes after the first multiday tour
that sqr thing looks just the the job - however some of Carradice's own pictures seem to indicate it's purely fixed to seat post (via their bracket) and cantilevered out behind. Is this right or does it also hang from the saddle as well , which would seem more sensible?