Continuous spark question

[izzy]

I got a 1979 XS1100 about six months ago and got it running and started tuning it but I've developed an electrical issue where it's sparking continuously, and the spark only gets fatter when it should be sparking and not turning off all the way. I've traced the wiring back and it's not shorting out just wondering if anyone has any suggestions or has had the same problem?
Any help would be greatly appreciated!
Thanks you!

-Izzy

[Radioguylogs]

12V is always provided to the coils, and the Ignition Module breaks the current to trigger the spark.

So, maybe the wire between the coil(s) and the Ignition Module might have an intermittent open, or the Ignition Module has a problem? Or the Ignition Module has an intermittent ground connection?

[Tonyxs11]

are you earthing the plugs on the head so you can see the spark ? hows the bike running ?

[izzy]

are you earthing the plugs on the head so you can see the spark ? hows the bike running ?

Yes, it's a constant spark but gets fatter when it's supposed to be sparking and it's not running at all anymore just a backfire here and there

[izzy]

12V is always provided to the coils, and the Ignition Module breaks the current to trigger the spark.

So, maybe the wire between the coil(s) and the Ignition Module might have an intermittent open, or the Ignition Module has a problem? Or the Ignition Module has an intermittent ground connection?

Okay, I'll check the wires and if that's not it should I look into buying a new ignition module or is there a way to repair it?

[Tonyxs11]

Yes, it's a constant spark but gets fatter when it's supposed to be sparking and it's not running at all anymore just a backfire here and there

not sure what you mean by "fatter" ? your getting a spark which is a good sign, is your problem somewhere else ? try a new set of plugs first before you fork out for a TCI.

[Radioguylogs]

Okay, I'll check the wires and if that's not it should I look into buying a new ignition module or is there a way to repair it?

Some folks have opened it and found cracked solder joints. They were able to re-solder them successfully. YMMV.

For the record, I have no way to know what your bike's problem is. I'm just offering ideas to help you find it.

You might want to measure the resistance of the pick-up coils since they are a common source of Ignition failures. There is a connector above the fuse box that is easy to access for these measurements. See the factory service manual for details. However, I don't know how they could cause the problem you describe.

[DiverRay]

You do know this is a "wasted spark" engine, correct? The two plugs on the coil with BOTH spark at the same time, even though only one is on compression stroke. If that is what you are seeing, it's normal. So 1 and 3 will both spark at the same time, and 2 and 4 will spark at the same time.

[Tonyxs11]

You do know this is a "wasted spark" engine, correct? The two plugs on the coil with BOTH spark at the same time, even though only one is on compression stroke. If that is what you are seeing, it's normal. So 1 and 3 will both spark at the same time, and 2 and 4 will spark at the same time.

do you mean 1 and 4 then 2 and 3 ????

[red bandit]

do you mean 1 and 4 then 2 and 3 ????

Agreed. And DiverRay knows this. He must have had a senior moment like I do.

[Tonyxs11]

Agreed. And DiverRay knows this. He must have had a senior moment like I do.

yep, we all have them

[Hydroman]

I've never had a senior moment........ Well at least not that I can remember.