I've got a Topeak Road Morph frame pump mounted below the top tube of my 2005 Trek 1200. The pump has a single bracket in the center. Problem is that when I'm riding and go over any kind of bump, the ends of the pump knock against the top tube with an annoying rattle. The mounting strap is tight around the tube.
Also, the pump prevents me from carrying a large water bottle in my second bottle cage (on the seat tube).
Any suggestions for different mounting position/location/strategy? The rattling is driving me nuts. I thought about wrapping velcro around one end of the pump or something, but it looks like that would interfere with the cables running underneath the top tube.