Time to shift gears for a bit. The last "difficult" task on this bastard child of a bike is the wiring harness. Before anything can be made, a really good plan is needed. I can fabricate steel like an old lady bakes a cake: a little of this and a little of that looks about right and taste good in the end. For most of what I make in steel, I don't need to make prints before I start cutting. The act of wiring is easy for me and I can make my own prints, but I have to write it all down before I start because I cannot work out of my head as I go. Before we go into the actual schematic, we need to talk about handlebar controls. When I went to test ride the Suzuki before I bought it, I couldn't find the kill switch. The seller explained that the light switch or the key would kill the engine and showed me a kill switch where the 640 Adventure has a trigger switch for flashing the brights. The handlebar control on the left is a Leonelli 074 that was used on some spanish bikes and included in Baja Designs dualsport kits prior to 2011. This switch setup is better than the KTM switch because in addition to the turn signal and horn, it integrates a kill switch and has a position designed for running without the headlight on. That means that this switch will do everything the left KTM switch will do, half of what the right switch does, and something neither switch will do. The drawback to the Leonelli unit is there is no trigger to flash the brights and it is much more difficult to rebuild the switch. I was worried about build quality but after rebuilding both switches, I am confident in the quality and happier with the more straightforward turn signal switch. The Leonelli turn signal does not feature push to cancel but is more robust. Here's a picture of the switch I'm using: One of the features that I want to include in this build is the ability to separate the essential circuit from non essential ones. Ideally, there should be a way to turn off or remove every circuit that isn't needed to get the bike out of the woods. This allows the bike to run even if something non essential is broken in a way that it is causing other components to fail. Using the aftermarket handlebar controls rather than KTM will make this task easier. Additionally, when kickstarting or bumpstarting a bike with a dead battery, it is much easier if the lights are off. The lights draw enough power from the stator that the spark to ignite the fuel is significantly weaker with them in play. I went on a mission to find a wiring schematic for the Leonelli 074 handlebar controls and was surprised that none were available. I found where others had asked for one and where others had a magic box on their schematic but no one had a list of which wires were connected when each switch was used. I busted out the multimeter and made my own. The problem for me arrises with my new headlight. The light has 3 wires in: hot for high, hot for low, and ground. I want the low beam and high beam on while high beam is selected, low beam alone when low is selected, and no lights when the switch is in what I am calling run. I have used a pair of relays in the past to make a circuit that acomplishes the above that I could attach to the Green/Blue and Yellow wires but I shy away from relays as much as possible. They are a moving electric part and therefore not as robust as a hard wired circuit. I decided that if I could remove the connection between Red and Blue in the run position, I'd be able to have power fed in via Red, out for all lights except high beam via Blue, and out Yellow for high beam. Some tinkering turned this: Into this: And now there are no completed circuits in the run position.