PAMCO 400E ignition trouble shoot, help!

I'm not an EE, but it sure looks to me like the rectifier will feed power to the ignition system even when the switch has been turned off. And when the switch is turned off, the battery is disconnected from the circuit. But the engine is still turning, the stator and rectifier are operational, and that power has to go somewhere. Without the battery there to act as a buffer...

I'm going to guess that is what is frying the ignition.
 
Ok so, 10a fuse on the power to ignition system, easy enough. And I can swap that 30a to a 20a.

I'm not following what you said tho Dave. Do you mean the rectifier lead should be going to a different post on the ignition switch?
 
To closer match the stock wiring diagram the rectifier red wire should connect between the battery and main fuse.
 
Like @BBS360 said, the charging system output has to be connected to the battery at all times. Since the rectifier has been "disconnected" from the battery while in operation, you should go through the testing proceedure for it. It is quite possible that it may have been damaged by the abuse.

To summarize: you need to correct your modified wiring harness before you buy another ignition system.
 
Makes me wonder how many bikes have been wired with that diagram.
The field coil voltage should get cut at the same time as the rectifier so there shouldn't be much stray voltage for prolonged periods. Possibly enough residual magnetism in the rotor and leftover emf in the system for decent voltage spikes, stressing the electronics every time the ignition is switched off.

This is still not ideal but might give you an idea of what Dave's saying.

Crappy Wiring Diagram.jpg
 
oh wow, this makes so much sense. holy crap, thank you boys, you might have just solved it. time to put in some work!

and @BBS360 my guess is A LOT of bikes wired with that diagram; we found it online, gee thanks google.

on that note, this diagram you just posted looks legit. however, you said "still not ideal", which makes me hesitate to use it. is there a specific reason it is not an ideal plan? because i was about to follow it!

hey thanks again guys, for taking the time to help me out!
 
I'm no electrical engineer either so I'm just cautious recommending things.
At this point I don't think there's anything electrically hazardous.
There's no kill switch, or flashers of course, but it is supposed to be a minimalist wiring diagram.
The original showed the regulator feeding field coil brushes. Our SOHC bikes are brushless. Might have originally been an XS650 diagram.
Could be clearer and organized better.
Running a common ground wire might be a good idea.

It's still based around that ignition switch/starter combo. Not sure if anyone has found that specific switch yet but it seems a little odd. Should at least be mounted to have a good ground since the starter relay grounds through the switch.
You're not using the starter so it's not an issue.

Even with everyone's suggestions you might still need a new TCI/pamco.
 
ok, that all makes sense. thank you for being so clear and specific!

the switch i believe is the same cheap replacement switch i got from the auto parts store here, i think Autozone. cost me about $8. it's identical to the picture.

thanks a ton @BBS360 @16VGTIDave @xschris and everyone else for your expert help!!
 
Hi guys, I’m back on this bike after yet another year of it sitting.

I received a new pamco from Pete to replace the other one. Before I plug it in, I think I would like to buy new coils.

Can you guys recommend which coils are best? Best meaning: least likely to damage my setup, and preferably idiot proof! I’d like to buy from mikesxs if I can, you know, support and all.

Thanks and glad to be back!
 
I took my coils into a yamaha mc shop, and had them bench test the coils. Mine surpassed spec. That is the most idiot proof way of getting coils. (determine that yours are fine) I believe the mech stated he hadn't seen a spark that strong. I heard it in the other room. Quite shocking. i guess.
 
I buy the universal coils from DimeCity. They are the same as Mikes but just a tad bit cheaper. You can get them for even less, as DimeCity sometimes puts their stuff on EBay and that usually includes shipping.

The original coils will be fine and they make good backups. The problem is that you can replace the wires on them. You will need to buy wires to go with the new coils and boots. You need to get resistor boots to go with the standard NGK BP7ES, or you can get non resistor boots and go with the NGK iridium plugs.. The iridiums are more expensive. I noticed a pretty big difference in the idle and overall performance with them and I use them now with my points setup.. I had the Pamco but it broke.. Id sure like to get the Pamco back...
 
Yes BBS360 you are correct. You just don't want a resistor plug with a resistor boot. Its one or the other. I haven't tried BPRs yet.

Ive used BP6ES, BP7ES, and whatever the NGK iridium is
 

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