I found two computer fans laying around at work. Put neoprene pads on the corners (cut from freebie Motorcycle Superstore mouse pads) and zip-tied one fan to the back of each radiator (through the fins and around a pipe). Got power from the headlight circuit, routed through a handlebar switch left over from the DS kit (and which I never turn off) and haven't boiled over since. The fans are very inexpensive, so even if I lose one to water or wear it is cheap and easy to replace. They are holding up well after riding much single track, dual sport, and in the rain once.