Xj650 Seca no start/ extremely weak spark

So ive rebuilt a couple of bikes in the past few years and decided i wanted a new project to beat on after i get off work everyday. So i picked up a 82 650 seca that supposedly had a carburetor issue. when i got there the gas tank and sides were off no battery but he had mostly everything. I talked him down to $250 bucks and i figured that worst case i could part it out and make some of it back. so i took a chance.

When i got it home and started messing with it after throwing a battery in there was no power at all because it kept blowing the main fuse, unplugged the rectifier/ regulator and it started right up. ran horrible but i figured that was the carbs/battery so i ordered a rectifier and got to work on the carbs. The carbs were spotless but i still deep cleaned them anyway. the airbox wasnt on so i figured that might be the reason it idled so horrible. put it all back together, put the new rectifier on and now it wont try to fire up a all, it just turns over endlessly. the plugs are wet so i know its getting gas.

Im getting extremely weak and intermittent spark and sometimes it would randomly shock me through the spark plug boot. when i checked for ohms on both of the ignition coils there was open resistance on both secondary so i ordered a set of coils. i happened to come across a article that said you check the yamaha coils buy testing for resistance from one plug wire to the other and not through the pigtail to the plug wire like other coils ive tested. sure enough there is 10k resistance on the dot from plug wire to plug wire. so i checked the plug boots and they are 5k aswell.
EDIT: ignition coils are both in range at 680 ohms when tested at the tci.

so before i go wasting more money on buying parts i dont need, does anyone have any insight on why it would fire right up and then now it wont? could the TCI have died that fast? nothing has changed on the bike, testing individual relays, kickstand, clutch, etc all work still. the only thing that changed is that after trying to get it to start for to days and everything ive checked the neutral light doesnt come on anymore but it will still try to start in nuetral with the kickstand down but i dont know if thats really relevant. i will add that when i take the plugs out to see spark its extremely weak. sometimes arcing on the threads and not the diod at the end. im kind of at a loss right now and any help would be greatly appreciated.

 

"EDIT: ignition coils are both in range at 680 ohms when tested at the tci." i meant the pickup coils. sorry it was late

 

If you got shocked through plug caps time to replace them. If you had regulator/rectifier unplugged you may have caused a Voltage surge, or a bad ground causing the problem. One ground wire on the seca goes from engine block to air box mount on left side

 

I plan on buying new plug caps. but in the meantime i took apart my TCI and played around with it (ive been a IT expert for 15 years and have repaired many PCB's). There was some horrible solder joints in there that i fixed up and you could tell it had been opened up before.Now my nuetral light works o.0
I tested the transistors, one was iffy and the other was definitely bad. So i ordered some replacements from digikey. The rest of the wiring through the bike was a hack job from the previous owner. crimps and twist caps were used everywhere and im pretty sure stripped wires were grounding somewhere. so i decided to just rip it all out and start from scratch when rebuilding it. I plan on doing a minimum wiring with no relays.

In the meantime What is the BARE MINIMUM to start this engine, i have the motor siting in the frame and nothing else and i want to be able to make it run before building it all back up. Im guessing just tci and coils connected to a battery? maybe the rectifier? that should be about it right? and just manually connect the starter to the battery to crank. Or is there something else im missing that is needed.

 

You have to have a starter relay or you will cook everything

 

ok, figured it wasnt needed too much because of how many people just use a screwdriver to jump it to test if its bad

 

The point of the relay is to keep sparks/ arcing away from the battery. While uncommon, battery explosions DO occur, and rarely end well.