The first summer I had my 750, that kept happening to me..one day, just to get home, I put in a 20amp fuse..I think it's still there..in the meantime, I've traced every wire on the bike, and found a lot of bare wires. I found a bunch under the seat, next to the fusebox...I taped them all, and eventually, the problem cleared up....the most vexing areas for me though have been the ones you can't see...inside the headlight, the junction between the main harness and the front end (under the tank). Check all connections! and make sure that they are routed properly...I had one connection in that bunch that was routed wrong, and one wire was shorter than the rest, so when I turned the handlebars sharply, the wire would pull out...of course I'd check the fuse and no blow...I got stranded a lot for a while...
By far the worst short was last year when the starter switch/headlight cutoff switch disintegrated...I'd be riding down the road, and all of a sudden, my headlight would go out...finally, the starter didn't work either, and the button stayed in...finally, I put a new pushbutton for the starter, and a second light switch in...my starter works fine now, but the most remarkable thing is that for the first time in nearly 4 years, my headlight is as bright as any newer bike, and everything works as it should!
I guess what I'm saying is with electrical problems, everything is connected. If you are blowing fuses, or even have a dim light like I did, you have a short, and your life will be miserable until you find it. For me, trouble shooting my bike was like having a handicapped wife...I love her to death, but eventually,through loving care, I was able to find areas in her that were especially problematic (loose wires under the seat, under the tank, in the headlight etc.), and once I found those, it became much easier to keep her comfortable.
