Making a wiring harness - 1982 Gs 400 L

[Ashton391]

Good afternoon,
I have a 1982 GS 400L that is in rough shape. This is my first bike rebuild/custom job that I am trying.
I am currently rebuilding the engine, and hopefully rebuilding the whole bike into something custom.
(no real plan yet, just a few ideas)

I was wondering if anyone had any insight into making a custom wiring harness using aftermarket parts.
Are voltage rectifiers, ignition coils, head light, *really all electrical components interchangeable?
Are control modules interchangeable? Can I just order something off of amazon?
Can I use aftermarket digital Tachometer/speedometer?

Is there any major problems I will face trying this?
I do have some experience working on electrical systems, I just don't know a lot about the technical side of it.

[tom203]

How rough shape?? Does it have the original harness? Making a harness from scratch is time consuming. You need to understand the original layout and components before you go amazoning.
Have you seen this diagram? It's a slow loader ,so be patient

https://onedrive.live.com/?cid=2370B62DDF9F0C6B&id=2370B62DDF9F0C6B%211033&parId=2370B62DDF9F0C6B%211030&o=OneUp

Edit.. Try this, my ipad is fighting me

https://skydrive.live.com/?cid=2370b62ddf9f0c6b&sc=documents&uc=3&id=2370B62DDF9F0C6B%211030#cid=2370B62DDF9F0C6B&id=2370B62DDF9F0C6B%211033&sc=documents

[sam000lee]

If you think you're up for it, I say do it. I learned a ton when I made a harness for my GS450. My advice:

- Get a couple of the kits from http://vintageconnections.com - it looks like they just updated the website which is nice. I got the regular bullet connector kit as well as a latching connector kit.
- Don't bother buying different spools of colored wire. Go on ebay and buy a used harness for your bike (or just use the existing one). Once you've unwrapped it most of the wires will be in really good shape, will contain all of the colors you need as well as a lot of splices that are hard to recreate well
- You shouldn't need a lot of aftermarket parts. I would certainly do the usual "GS" stuff that people on here recommend which boils down to installing an SH775 and implementing a single point grounding system. I'm not sure what you mean by "control module". Something like the motogadget M-unit will make your life easy for a couple hundred bucks if you choose to go that route. Putting things like LED lights into the stock system doesn't always work without additional fidgeting but if you're building from scratch you can address that while making your wiring diagram.
- Digital tach is easy since those often can splice into the coil trigger wires. I've never looked into a digital speedo but I imagine that if you're building the rest of the harness you'll be able to figure it out.

I would start by breaking down the entire system down into sub-systems such as "charging" and "lighting" and then drawing separate diagrams for each of these systems. There ends up being a lot more than you would think. For example, the gear indicator has 7 lights in it. You'll end up with a master list of all the components. Here's one for the charging system (missing a fuse) from when I did this:



You'll end up with something like this after you put it all together: