Chapter 13 - Wiring, Part 1
Since the frame got stripped bare, and there was really no point in trying to hack up the stock General harness, and the KTM has only two wires (ground for the coil/TCI?/CDI? magic box, and power/trigger from the stator), I figured I would start from scratch and make exactly the harness I need. Goals here:
Practice with planning ahead, instead of slapping stuff together because it's a decent workout for the brain, and a good habit that mopeds have a way of making you want to avoid (for me, at least).
Ease of use because I don't plan to run the wideband or EGT all the time. Disconnecting and removing them should be quick and easy. And I expect the harness will see a few full removals and reinstalls for things like paint, more fabrication work, etc., so I want to be able to pull the whole thing out of the bike quickly without having to cut any wires.
No bullet or spade connectors, except where needed, like on the ignition box. I want weatherproof, easy to disconnect, durable. I chose Weatherpack here, because I had a kit on hand, and they're cheap and readily available. There's better stuff out there for sure, but for now this will work. Not a big deal to upgrade to better connectors later if needed.
Practice building a quality harness, one that either looks good or looks (mostly) invisible, or both. Added durability goes hand-in-hand with this. So I'll be using some sort of sleeving for it, which also forces me to plan ahead (see first goal).
First step, then, is to plan! Did the best I could here (using some electronics CAD here would have been a good idea, but whatever), including adding rough splice locations ahead of time. The electrics on this bike use two relays (one for gauges, one for lights), 5 switches (keyed ignition, kill button, lights, high beam, and gauges), and quite a few connectors, maybe 18 or so, to disconnect the various bits:
Used that to start laying out the wire on the bike. This part took a ton of time, since I wasn't entirely sure where everything was going to live. This is also a good point to mention that this is set up to not rely on any power generation - this bike won't be used for hours of riding on end, and with something like a 5000mAh battery, the headlight (30W, supposedly, 45W high beam, LED all around) should last a couple hours. Taillight is the Treats vertical fixation, so not much power draw there. Wideband uses something like 3A since it has to heat the sensor, but that won't be used too often once the bike is tuned.
Here's most of it layed out on the bench. A few of the splices got a little rearranged, but for the most part the initial sketch of the layout was pretty close to what I ended up with: