Re: Ignition points open opposite of TDC? How to fix

Ok, so here is a helpful wiring diagram. It may not be exactly like your bike but it should be instructive.

You want to keep your eye on two wires in particular. They’re both from the ignition coil, which is underneath the one most visible in your most recent pic.

One is usually blue, and it comes up from the stator to the terminal block, and from there to the big, chunky, plastic-looking high tension coil. That coil should have another wire grounded to the engine, and of course the wire to the spark plug.

(The kill switch is usually wired in here somewhere. Identify that wire and take it out of the terminal block for now. If you get the bike started without it, you can shut it down by sticking a potato on the exhaust. This is how ASE-certified moped mechanics do it all the time.)

The other is usually blue with a black stripe, and it sounds like you found it. This is the ignition ground. It goes to the terminal block, and from there it should go to something bolted to the frame or the engine or something. If it’s sharing a slot on the terminal block with some other wire, remove that other wire for now and check the ground connection — you want it someplace clean and free of paint, rust, grease, etc etc.

Re: Ignition points open opposite of TDC? How to fix

You don't set the points where it fires, you set the points AT top dead center. You might've already been doing that but it kinda sounded like you were setting the gap at the point you want it to fire.

Re: Ignition points open opposite of TDC? How to fix

Tried disconnecting the kill switch and the wire that was in the same terminal as the blue with black stripe. Forgot to mention on the opposite terminal as the blue and black stripe, that orange wire goes around the the big plastic coil thing, which does have another orange wire connecting to a bolt.

Re: Ignition points open opposite of TDC? How to fix

> Nick MBC Wrote:

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

> You don't set the points where it fires, you set the points AT top dead

> center. You might've already been doing that but it kinda sounded like

> you were setting the gap at the point you want it to fire.

Yeah, I set it at tdc. Idk how it changed but now its opening pretty advanced, ill get that sorted again once I get spark back

Re: Ignition points open opposite of TDC? How to fix

^^ forgot to say disconnecting those wires did not give me spark

Re: Ignition points open opposite of TDC? How to fix

This coil doesn't look good, I probably scraped it up with the flywheel when my stator was loosened. Could that be the culprit?

20210609_193627.jpg

Re: Ignition points open opposite of TDC? How to fix

> Aidan Schmidt Wrote:

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

> This coil doesn't look good, I probably scraped it up with the flywheel

> when my stator was loosened. Could that be the culprit?

You got the right idea in your video. Solid blue to HT coil, blue/black to ground, orange is either brown or what someone used instead of brown and should also go to ground.

I’m pretty sure the scuffed coil is for your brake light (and the green wire with brown stripe is its ground), so it shouldn’t affect spark. The ignition coil sits directly beneath it.

The condenser (the cylindrical thing with the blue wire connection you noted in the video) might be failing or fried, which could cut or hamper your spark. If you pull the clutch lever and pedal, can you (or a friend) see sparks around the points, by chance? That would be a bad condenser symptom.

Also possible that one or more of the connections at the HT coil is dicey. No problem, just pull the little bootie things. There are traditional spade connectors underneath them. The spark plug wire screws into the coil, or rather is screwed onto it — again, easy to remove and replace.

The bike did have steady spark at one point, tho, right? I feel like I’m forgetting something obvious.

Re: Ignition points open opposite of TDC? How to fix

To test for spark and only spark, I just hard wire the blue to the HT coil and ground out every thing else. That allows me to see what is happening with just my ignition wiring. Find a nice solid grounding spot where you can have all the wires go except the blue. Once you have your spark sorted out then you can start reconnecting wires to see if there is a short somewhere that may be affecting your spark.

Since you have managed to get a spark out every so often, I'm going to lean towards either a frayed wire or one that is just not connected or grounded out properly. Sometimes wires get pinched and cut a little and end up grounding out on the frame unintentionally.

Re: Ignition points open opposite of TDC? How to fix

Just a random thought did you get them to open before TDC? I had a friends bike that was excited Laing the same situation. Sure enough they were opening after TDC. Turns out he broke his keyway. Put on a new keyway. and I was able to set them correctly.

Re: Ignition points open opposite of TDC? How to fix

Have you tried removing the plug and resting it against the engine and looking for kick over spark?

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