Electrical issues

[Mikes84interstate]

Hello all. I have an 84 goldwing interstate with 48000 miles on her my pride and joy. Went for a small ride a few days ago and it died on me. I found the fuse that I put in the two red wires on the starter relay was loose I put it back in and it started but ran like it was only running on two cylinders. It backfired rather loudly out the exhaust the whole way home . When I got home I noticed that my tail lights wouldn't turn off with the switch but when I separated the two red wires by the relay from the fuse holder that I have hooked to the battery they went off but I have no power to anything else either. I'm stuck so any advice would be greatly appreciated. Also I might mention that within the last 500 miles I have put new water pump timing belts thermostat pulse generators coils plugs and wires rebuilt the carbs new front and rear wheel bearings new u joint new swing arm bushings the yellow wires are all hard wired that come from the stator I also have a volt meter hooked up to the hot terminal of the fuse box it's reading 13.5 when I'm riding it it also stays on when I shut the key off now didn't before. So thanks again in advance for any information I'm really stuck.