Pug 103 brake light blowing. Robbing spark when not blown

Has to build up a ignition stator plate for a pug 103 that had a ramsey CDI. The CDI was of poor design so I scrapped it.

I have probably built 25-30 ignition stators for 103s in the 12 years I have been building these. For some reason this bike is acting stupid. I always do my initial spark and lighting tests with a drill spinning the motor and looking for spark and working the light switches.

On this build I see that when I spin the motor the plug is sparking and when I hit the brake lever the brake light lights but is very bright and is pulsing the same as the spark plugs spark which at the same time disappears .

I have always used 6V 1145 twin filament bulbs in 77-78 103s

I have never seen the brake lights filament glow so bright from spinning with a drill nor have I seen it pulse the way it is. Its as if the spark is suddenly being transferred to the brake light bulb.

This one has me brain fucked.

Re: Pug 103 brake light blowing. Robbing spark when not blown

BTW these are two coil points stators I am building.

I had also taken the bike out to test the running and carb action . I knew that if I touched the brake levers the motor would quit so I was sure to let off the levers before I rolled to a complete stop so I could release the levers and not kill the motor.

Then I would put the bike on it's stand and reve the motor as high as it would go and squeeze the levers to watch the brake light. It was so bright and pulsing that it blew the bulb.

Now for more weirdness. With the brake light blown I could still ride the bike but now when I used the brake levers the bike would stay running until about the last five feet of rolling then the motor would cut off.

WTF huh WTF!!! this is a new dilemma I have never seen.

So I start to think the coils is internally shorted. I come back to the house and remove the stator and solder in another used coil. I start to do drill spin tests and same thing Bright pulsing brake light and the spark goes out.

So I start to think grounding, and I run a clip lead cable from the brake light socket to the head. Same trouble.

I guess I need to take a known good working stator off of a motor and bolt it up and see what the fuck.

Anybody have this happen??? (edited)

Re: Pug 103 brake light blowing. Robbing spark when not blown

What is your headlight doing?

Re: Pug 103 brake light blowing. Robbing spark when not blown

head light is working

Re: Pug 103 brake light blowing. Robbing spark when not blown

The 103 is wired as ext ignition ground, correct? Meaning, NC switches and brake light running off of ignition side ground. Some are gonna say you need that resistor thing by the back rack or one in your tail light, etc but:

1. you are getting ground from somewhere, since runs with levers pulled, light blown.

2. your brake light is wired into the wrong side of the coil

I just had a similar issue on a city bike, literally did the rev up/brake lever thing for 5 mins brake/throttle, On/off to try and blow it out, silly. Spent a day getting nowhere and gave up.

Re: Pug 103 brake light blowing. Robbing spark when not blown

Well that seems like a good theory to me Pat but the OMG ignition coils all have the HT wire soldered to a tab that runs out the back of the coil so it can exit out the top of the stator and not interfere with the spinning fly wheel. I cant see how a person can wire a coils in the wrong configuration.

I just took the stator back off and I'm going to grab one off another motor.

This is just so weird as I have not seen the brakelight strobing so bright to the point it blows.

Here is the stator. All seems well. This is the second OEM coil I have soldered into this ignition.

faultystator001.JPG

Re: Pug 103 brake light blowing. Robbing spark when not blown

Another thing I should mention about this bike is that when I got it the wire harness was cut away midway so that only the three wires, yellow, white and black remained running to the tail light. All of the wires and switches forward were missing.

Lucky though I had a near complete savaged harness that I spliced the tree wires from the tailight then threaded the harness into position.

Re: Pug 103 brake light blowing. Robbing spark when not blown

The resistor under the seat is in position and wired in. I removed it briefly and OHMed it with some others I had and they all were the same so I cleaned the contact points and bolted it back.

Re: Pug 103 brake light blowing. Robbing spark when not blown

condenserswires002.JPG

For a while now I have been building my stator plates using these old style condensers that I bought in bulk from Moped Larry a year or so ago. Always had good luck with them so far. Staring to wonder if I finally soldered in one that is possessed and that is the cause of my trouble.

The bike runs perfect ignition wise though Grrrrr!

condenserswires001.JPG

Re: Pug 103 brake light blowing. Robbing spark when not blown

I've never had one of those coils work, they heat up, spark all over, and puke. Looks like on the coil theres two soldering tabs, that's what I mean't.

Re: Pug 103 brake light blowing. Robbing spark when not blown

Yes I get you pat. Actually three solder tabs. One for the HT plug wire Then the right hand tab solders on the brake light wire. Then the left hand tab solders on the were to condenser/points

Re: Pug 103 brake light blowing. Robbing spark when not blown

Ok so I bolted up a Known good working stator and gave it the drill spins. Same scenario. This tells me I need to stop looking at the stator plates and start looking for shitty grounding paths.

brakelightwires001.JPG

Re: Pug 103 brake light blowing. Robbing spark when not blown

Took apart the headlight and spun the bucket mounting bolts to make sure that the toothed washers were digging in to the metal to provide a good path to the bike frame. The two black ringed ground wires in there I cleaned as well. Give the motor a spin. Still the same fault.

Re: Pug 103 brake light blowing. Robbing spark when not blown

Moved to the tail light and disassembled to make sure the yellow wire was going to the "T" connector and the black wire was on the "S" connector. Pulled both connectors on and off to make sure they were clean and tight.

moved to the blue grounding wire and gave the bolt a few tight turns to dig in the metal path.

Give the motor a drill spin and Hooray! The brakelight lights up as it should with no more pulsing and the spark is no longer being robbed away.

brakelightwires002.JPG

Re: Pug 103 brake light blowing. Robbing spark when not blown

So all is Zen now with this bikes electrics. I guess what I learned is that is no matter how long your in the moped game, if you get too comfortable, you can fall for the same old gremlins.

Seems like every time I repair annoying electric issues that voice comes booming back in my head, "IT'S THE GROUND, IT'S THE GROUND"

So now I am thinking, with the shaky ground at the tailight, when I cut the clean ground by squeezing the brake levers the ignition coil in search of another path to ground only finds a weak dirty path so all the energy from the coil going to the spark plug gets backed up in the brake light bulbs filament causing it to pulsate and burn twice as bright at the same time killing the spark at the plug?

If wish someone could put this into better words to relay what I am thinking

Re: Pug 103 brake light blowing. Robbing spark when not blown

only u could do it, but still don't make sense cuz u said it runs with busted bulb and both handles pulled.

Re: Pug 103 brake light blowing. Robbing spark when not blown

I KNOW THAT WAS THE MOST BAFFLING PART> WHY DID IT NOT DIE AFTER THE BULB BLEW TILL LIKE THE LAST FEET?

Re: Pug 103 brake light blowing. Robbing spark when not blown

Stoked you figured it out! So the blue wire wasn’t plugged in or just not making a good contact?

Re: Pug 103 brake light blowing. Robbing spark when not blown

Well the blue wire was grounded to one of the bracket bolts. At some time someone had built another identical ground wire on the other bracket bolt. I actually just put a socket on the grounding wire I chose to use and wormed it back and forth to be sure that the bolt/wire was digging into the metal of the fender to create a clean grounding path. That cured the bottleneck of electrons that was wreaking havoc on the brake light bulb element and robbing the spark from the plug.

Re: Pug 103 brake light blowing. Robbing spark when not blown

This why I try to run a dedicated ground wire . It eliminates the frame as ground and all the possible weak points .

Re: Pug 103 brake light blowing. Robbing spark when not blown

Yes good point PD. Doing rescue builds for resale though you try to cut your Labor. But then if you spend 4 hours swapping coils and stators I guess it's a wash.

Re: Pug 103 brake light blowing. Robbing spark when not blown

> cheetahchrome . Wrote:

> -------------------------------------------------------

> Yes good point PD. Doing rescue builds for resale though you try to cut

> your Labor. But then if you spend 4 hours swapping coils and stators I

> guess it's a wash.

I'd trade a yard of wire for just 10 minutes worth of chasing , any day .

Wire is a sure thing , unlike chasing ... anything . ;)

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