CDI / PMA Capacitor Question

[kungfutoast]

Maybe someone can help me out. I am sure I am over looking a very simple solution...

I setup the stock Hughs CDI/PMA kit with the relay and capacitor - no battery. I cannot get spark. If I unplug the relay the bike fires up just fine, however, I do not have lights or bike theft protection. I hooked up a temporary battery and the system will work as it should. I hear the relay triggering and the key switch works as it should.

I watched Hughs Facebook video that shows the setup. Hughs Video I have this exact setup but with an LED brake light and a standard bulb headlight (on a on/off switch).
His video shows the system working normally. So, what am I missing here? The system should just kick on over. Is my capacitor not a high enough rating? Below is the style of cap I am using.

I would love some helpful thoughts.

 

[jpdevol]

Just a guess: The relay in Hugh's system grounds the ignition when the stock kill switch is in the off position it has to have power present to the relay to not ground the ignition. If your capacitor is not holding a charge it will close the relay grounding the ignition. perhaps it takes a few kicks to recharge the cap.

If I were running a capacitor, I wouldn't use the relay; I'd be using a direct grounding kill switch instead

 

[kungfutoast]

This is totally what I am thinking. I'm sweating my ass off in 100* weather trying to kick it over. It's not pulling in enough power to fire the system. I do have a direct to ground killswitch inline with the coil. Without the relay, you can kick the bike over but it renders the key switch useless. It pretty much bypasses the switch. I would like the bike to not get easily stolen.

 

[Vincenthdfan]

I would like the bike to not get easily stolen.

In Portland? I wouldnt take my eyes off it...kill switch or not!

 

[kungfutoast]

bwhahahaha seriously!!!!

 

[arcticXS]

I would recommend an ignition lock and a kill switch from a bike that comes with a CDI ignition from the factory. Both of these will GROUND the "kill" wire from the CDI when in the "off" position, and interrupt this connection when in the "on/ run" position. With this setup, there is no need for a relay.
Relays on CDI systems are there to convert NO function on ignition and kill switches designed for battery powered ignition systems to NC.

 

[kungfutoast]

Thanks arcticXS. I was considering this but am at a loss for sourcing such a switch. I found this cheap one on amazon...

key switch <--- it's not much of a looker. I have one on a honda with a lifan motor. It is pretty much the same setup.

 

[arcticXS]

You need a NORMALLY CLOSED ignition lock. Not normally open, as the one in that link.

 

[jpdevol]

Thanks arcticXS. I was considering this but am at a loss for sourcing such a switch. I found this cheap one on amazon...

key switch <--- it's not much of a looker. I have one on a honda with a lifan motor. It is pretty much the same setup.

https://tcbros.com/collections/metr...of-ignition-switch-with-momentary-start-13-16

I'm using this switch from TC Bros (but I don't use the electric choke function). If one M is grounded and the other M wired to CDI "kill" wire, it will work for your purpose. Good quality switch

 

[kungfutoast]

https://tcbros.com/collections/metr...of-ignition-switch-with-momentary-start-13-16

View attachment 249207
I'm using this switch from TC Bros (but I don't use the electric choke function). If one M is grounded and the other M wired to CDI "kill" wire, it will work for your purpose. Good quality switch
View attachment 249208

Oh dope! thanks so much yall.

 

[kungfutoast]

hmm is it safe to assume the M/M terminals are all I really need. The bike I am running is kick only.

 

[arcticXS]

hmm is it safe to assume the M/M terminals are all I really need. The bike I am running is kick only.

M+M for ignition, A/B/C can be used as a light on/ off I guess.

 

[jpdevol]

The M terminals, wired as above (ground/kill), will disable ignition with key off and removed. You'll still use B for power IN from battery and A for power out to lights and other loads. If you do use electric start, the Yellow/red wire from the solenoid would connect to S with the solenoid black wire connected to ground

 

[kungfutoast]

Ok, so I got the key switch installed and it does a great job solving for the killswitch! Stoked on that thank for the suggestions everyone.

I am still however having the issue of no power to my lights. I have the attached image for my setup. Am I just touched in the head and not getting this whole electricity thing? Shouldn't the capacitor be receiving the rec/rec power from the stator (yellow wires). Which would be sending a regular flow of current to the fuse box and ultimately to my accessories?

 

[jpdevol]

You may have just omitted it in the drawing, but the lights also should have a ground wire. Also, the kill function may work on the coil positive lead (as shown), but the CDI box has a wire provided for the kill function - don't know if the method in the drawing may cause damage

 

[kungfutoast]

hah yes I did omit the light grounding wires. They are in place tho. The key switch ground shouldn't be an issue. Seeing as how the instructions say to us a grounding killswitch in line with the coil if you are running the bike with out the relay + battery. Which applies to my bike.

Do you have any suggestions in trouble shooting the lack of power to the lights? Am I wrong in assuming the reg/rec should be sending power from the PMA to the Capacitor via the red wire which would send it up stream to the key switch and down to the fuse box?

 

[jpdevol]

Do you have any suggestions in trouble shooting the lack of power to the lights? Am I wrong in assuming the reg/rec should be sending power from the PMA to the Capacitor via the red wire which would send it up stream to the key switch and down to the fuse box?

That is correct. Do you get 12+ volts on that red wire?

 

[kungfutoast]

No... I literally just tested it and came back to your message. I'm getting like 19mv! Ooof. Unless, I am tested the unit wrong I read .5v on both yellow lines in one direction and OL in the reverse direction.

 

[jpdevol]

Hmmm. The yellow wires should carry alternating current: I'm guessing 15-20VAC at around 2000rpm - measured between each yellow wire (not to ground). The rectifier/regulator should then convert that to DC also guessing approximately 14VDC (measured between the red wire and ground). I suppose you're getting spark OK, so there must be some output from the stator

 

[kungfutoast]

yeah we are on the same wave here. I am getting healthy spark. I'll do a test on the yellow wires from the stator tomorrow and see what it is outputting. I would image about 15-20vac. Since this system does not need a power source (battery or cap) It doesn't rely on the 12v. I might jump to the assumption that the problem is in the reg unit. That it is not sending out the 14VDC and just shunting it all to ground? Like a bad diode.

Appreciate your thoughts. Im going to settle into some articles on testing regulators for the remainder of the night.