Hacked up Motorcycle

I got this nice little vintage motorcycle (circa 1980) for a song off of craigslist. Though it has it's issues, I've become attatched to it. It handles nicely and it's not too much bike for me to handle comfortably. Now if it would just run consistantly...

I put in quite a bit of work on the carburetors, ordering some new parts (a needle valve and a new float) and replacing them myself with the help of a friend. The bike didn't really start working until I put a fuel filter on it. My theory is that rust in the fuel tank has been gumming up the needle valve inside the carb., which then keeps the needle valve open though the bowl is full and ends up flooding. Since I added the fuel filter she starts right up (within two or three kicks) every time.

Now I just have electrical problems. A new battery was the most obvious thing to make my turn signals, instrument panel, and headlight work. For a while that seemed to have been the only problem, aside from the horn not working. However, the more I rode the bike, the weaker the instrument panel became, and eventually the battery was dead. I really haven't been riding it that much, so I believe that the drain is happening during the relatively lengthy periods of disuse that the bike experiences. More than that I noticed that the low headlight doesn't work. This took me a while to discover, since I don't ride this bike at night.

So time to open her up and see what's going on.

I found this wiring diagram on the net by a suzuki enthusiast. This is quite a find, as wiring diagrams are pretty rare on the net in general. The
GN400 wiring is probably more compicated than it needs to be, but relatively simple as far as wiring schemes go. Considering that the electronic feature list on the bike can be counted on one's fingers, it's quite remarkable that there are so many wires.

Unfortunately, upon closer inspection, I discovered that my GN400 has a slightly different wiring scheme than the diagram shows. It appears that the original wires that went to the low and high beam circuits in the headlamp are both damaged and carry no power. So instead some prior owner has run a (very thin) wire from the switched rear brake light circuit to the high beam terminal on the headlamp socket. This tiny green and black wire weaves its way arouond the wiring harnes sheilding, periodically knotting around something for support, and just punches in through an after market hole in the lamp socket. I have to admit it's fairly creative, but I have to wonder whether the lack of power in the intended headlamp circuits has anything to do with my power drain...