I've never washed any of my bikes in the 15+ years that I've owned them, and they're very clean. I do wipe them down with a damp rag after every ride. I then lube everything. After that I go back over the frame with furniture polish. It works great and keeps everything looking nice. And a plus to not washing your bike with water is that you won't have to worry about flooding the bearings with water. Even the sealed bearings will allow some water through. You do need to be careful about grit on the frame to prevent scratches.