New Member in Edmonton with a '78 XS400


XS400 Addict
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Edmonton Alberta
Hi everyone,
I just picked up a 1978 XS400 and it needs a lot of work.
The previous owner started to turn it into a cafe racer, cut the rear frame, bought a cafe style seat, and put a set of grips and handlebar end mirrors on it, but then ran out of time and space to do it, so it sat in a parking garage for a couple of years untouched. "It ran when it was parked"
I managed to pick it up for $400 and bring it home, and started to look a little deeper, no leaks, but after sitting for a couple years there was some seepage around some gasket surfaces. The gas tank is rusted from the inside, it has a bunch of pinholes, so I'll be looking for a new tank. The keys were missing, so I plan to replace that with a hidden switch to help keep the handlebar area clean. The air box and air filters were removed. I also picked up a Haynes Manual for it with the Chapter 7 Addendum for later models.

Here is my plan of attack.
1.) Confirm/ensure that it runs by cleaning the carbs and charging the battery, put some fresh oil in it and see if it will fire it up. I hooked a battery charger to it, bypassed the key switch, sprayed some carb cleaner into the carbs and gave it a kick. It fired right up, so we have spark...
2.) Get it to an active title again, get it road legal, inspected, and registered.
3.)Tear it all down and commence to modifying.

A couple of questions.
1.) It is a 2L0-0 serial number, which would indicate that it is a 1978 XS400E. However, that does not match with the wiring on the Key Switch as per the wiring diagram for the E's. The Key Switch on the bike has a Red, Brown, and Blue wire as per the 1979 XS400F. The date of manufacture is 10/77. Has anyone else experienced this?
2.) As I look closer, the wiring is pretty rough, should I just start from scratch and build my own schematic/harness? Does anyone have a good basic schematic to start off with? One with no starter and a bit of a minimalist approach? I figure if I'm going to start from scratch I may as well make it as simple as possible.

Thanks in advance for all your help, and I really appreciate all the great info already on here.
A few pics...