1980 Yamaha xj650 intermittent spark issue

I recently got a 1980 Yamaha xj650 and it's had problem with occasional spark. I can occasionally get the thing to get spark but can't figure it out. I replaced the ignition coils and that seemed to fix my problem for about 10 seconds of turning over and then I haven't gotten them to work again. They were some cheaper china coils so I don't know if that my problem. I used the old ignition caps and have some new ngk plugs for it so I don't think that would be the issue. How many volts should the coils be receiving to work. Any ideas of what could be wrong.

 

thes are the coils I used

 

Check the TCI module? This is what actually controls the coils via signals generated by the pickup coils under the left side cover. They're specific to the engine in that they also have the correct timing curve for the displacement, they're also known to have problems with bad solder connections inside causing intermittent spark. I'd recommend running through the diagnostic checklist from top to bottom before firing the parts cannon. Being in Albertville you're not far away from me.

 

One of my buddy's has a Yamaha vstar 650 would that have the same tci module that I could check with

 

one of the more common failures on these bikes is the fuse panel on top of the air filter box. The clips that hold the fuses get brittle and lose the tension needed to make a solid grip on the glass fuses. A fairly easy fix to replace the whole panel with a blade fuse panel. Len at XJ4EVER.com has a nice kit to do this with. A link to his page is in the upper right corner of every forum page here. All the automotive chain stores have a similar fuse panel available as well.

 

That was already done one my bike tho it dose seem pretty cheaply done. I can provide a picture of it later.

 

That is great. I would think next up is checking and de-corroding all the electrical connections. The TCI's are pretty reliable for an electronic ignition but there are a lot of places for connections to get dirty in 45 years. Yeah, I hate the ideal of doing that too but..... A tedious chore but sometimes the only way.

 

Did you test the original coils?

Maybe review the info in here:
https://www.xjbikes.com/forums/threads/xj-parts-catalog-section-d-electrical-system.44641/