This is kinda lengthy, but I want to give as much detail as possible.
I have a 94 Dyna, FXDS-conv, 1340. It had some upgrades done years ago. The man who owned it before me passed before I got it so I don't know exactly what was done. I'm pretty sure it has been cam'ed, and maybe a big bore. It looks like it still has the original coil, but the pick-up has been changed to the adjustable timing type. Has always run great.
I went for a long mountain ride today. About 1.5 hours in the rear cylinder quit firing. I stopped along the road. It would idle on the one cylinder. I pulled the front cylinder plug wire off the coil and it died. There was a spark jumping between the coil and the wire before it died. I started it back up. I pulled the plug wire off the rear cylinder at the coil, no spark, and it kept running the same. So obviously coil isn't firing on one side. I checked the wiring for a broken wire or bare spot shorting out. Everything looked good. So we turned around and headed back down the hill to the nearest town(mostly downhill, could coast most of the way). About 10 minutes down the road, all of a sudden it started running fine again. So I pulled off the road again. Everything seemed fine. So we headed on up the mountain again(I know, probably not a good idea.)
So we rode for about another 1.5 hours before stopping for lunch. Then another 2.5 hours to the next town. About 5 miles before that town the cylinder went dead again. I stopped at a motorcycle shop where we checked a few things. The coil ohmed out ok, plug wires are good, but verified no spark on the rear cylinder side of the coil. But they didn't have any parts for it there(small town shop). I called AAA to tow it home. They were going to take 6 hours to get there so we went to get something to eat while we tried to figure out what to do. We were still about 60 miles from home. So after it set and cooled down, I fired it up. Running great! So we decided to try and get home. I pulled the chrome cover off the coil and module/breaker panel. I thought maybe the module was breaking down from heat. So we hit the road. Nope. Got 6 miles down the road and the cylinder quit again.
Thoughts? Any common problems? Coil? Module?
Any suggestions greatly appreciated. Thanks.

 

sounds like a module, look in side the nosecone and see if there is a module other than the stock pick up mounted in there.I just went through all of this...Brought coil, pickup but did the samething. replaced module with s@S hi4n module and off she went headache fixed... it also simplifies the ignition circuit. If you figure it out or need a module for the nose cone i have a new one s@s hi4n in the box . pm me

 

UPDATE... Got the bike home this morning. Checked the module. This is what I found. Definitely not stock.

 

Update 2.... I swapped the negative signal wires on the coil and the plug wires. The same half of the coil still isn't firing. Bad coil.

So new question... does anyone know if the coil on the new version, HI-4N, is compatible with my system? Looks like the same set up, 3 wires. The HI-4N system is compatible with my bike, but I would rather replace a coil than the whole system.

 

have you looked at the ignition pick up in the nose cone ,(as stated above ) what kind is it , is it the stock one or some aftermarket one ...???
if the coil is bad ,as you say ...it dont just fix itself and then go bad again ...!! the coil will either be burnt open are not !!!

this sounds like a loose connection somewhere !!! or the stock pick up is leaking the podding material out when hot ...(check the pickup in the nose cone)

why is the ignition setup for kick start...are you kick starting the bike ....and also ...flip the switch to single spark and try that ...
what coil do you have ...the crane dual fire are the stock single fire ...???

 

The whole thing is Crane. The pickup, the module, and the single fire coil. I know that it is improbable for a coil to go in and out, but I have seen it once before in an old Chevy pickup, so it's not impossible. I don't know why the previous owner had it set to kick start. This is the first time I've looked at it. It is on single spark. I did check the module in the cone, so did the bike mechanic.
When it quit firing it was the bottom half of the coil that quit firing. I switched the neg signal wires and the plug wires on the coil. If the module or pickup was bad, the non-firing side would have followed the wires, but it didn't. The coil still did not fire on the bottom. Which tells me the bottom half of the coil has a problem. Maybe there is something inside that is shorting out when it gets hot. I don't know. All I know is the way I tested it would either prove or rule out the coil being bad, because no matter which way it was hooked up the bottom half of the coil did not fire.
The coil I ordered is for the new S&S system. So if I am wrong about the coil, I can order the module that goes with it.

 

yes the s@s single fire coil will work with the hi4n ignition module.Mine did the same **** ended up buying a coil also but at the end it was the module ,, should have put one right away .... It would have saved alot of screwing around..

 

I can't help you with your problem other than to suggest you try posting in the EVO sub-forum. Lots of guys there that have forgotten more about ignition than I will ever know.

https://www.hdforums.com/forum/evo-classic-models-84/

 

So I replaced the coil with an S&S single fire coil, 15-1571. I also changed the plugs to an NGK BPR5ES-11. I had discovered that the plugs in it weren't resistor type and were also too cold. I was told that non-resistor type plugs will burn out a coil. That may be what started this mess.
I've put on about 200 miles in the last couple weeks, including a couple stop/go rides around town for over an hour. It's running great. Actually better than it has before. I later changed the plug wires to Moroso spiral core,32093-98, as recommended by Crane.
Hopefully this takes care of things for a while.
I hope this helps someone else out there, too.
Be safe and always shiny side up.

 

Solid core wires can and will take out electronics, especially aftermarket ignition boxes.
There is nothing good about solid core wires...at least for the past 25-30 years.
Bob