I just got a Topeak road pump and am trying to figure out the best way/position to mount its bracket so it will not get too much dirt. I have screw holes under the lower down tube, but that's the easiest to get dirty from the mud, dirty water on the streets... I don't have a top tube (it's a step through). I'm considering two alternatives: either wrap the pump in a plastic bag if mounted under the lower down tube--but the bracket will still get dirty over time; or to mount the bracket on the upper down tube next to the bottle cage.
I am interested in any better ideas about where/how you mount your road pump (keep in mind mine is a step through without the horizontal top tube). I hate to get the bracket and pump so dirty that it's hard to clean over time.