Bike Won't Start - New CDI, Magneto Coil, & Spark Plug Replaced/Installed, Still No Spark

Bary Kiddo

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My 100cc 2 stroke motorbike has been giving me trouble lately. Before I went and replaced the CDI, ignition coil, and spark plug, it had some occasional difficulty starting up. I figured swapping out these essential parts would sort things out.

Now guess what? No luck. Despite installing them right and connecting the red and blue cables to their appropriate terminals, the bike ain't producing a single spark when I try to fire it up. I mean, come on! I got compression and fuel, so why in hell isn't it working?!

Have any of you dealt with this kind of BS before? Any ideas?
 
I've had faulty parts right out of the box before, it happens. Put your old parts back on and change them out one at a time until you find the bad one.
 
Remove the plug, stick your finger in the plug boot and turn it over, spark is good if you yank your hand away, it's really good if you pee a little bit.(joking)

Ground the boot and check for spark, if it doesn't spark I would bypass the kill switch and try again.

If it does spark, try putting the plug in and grounding it, if it doesn't spark it means you have a very weak spark or you have a damaged plug.

Very simple system here, so look for pinched/broken wires, but Duds to happen.
 
Remove the side cover with the wires coming out of it. you will see two fixed arms on either side of a round magnet that spins. The arms must not touch the spinning magnet and be equally spaced.

If they aren't you will have spark issues.
 
…really good if you pee a little bit.
I choked on my cola.

How exactly are you checking the spark? Spinning the engine with a drill or pedaling while trying to see the plug?

Reason I ask is because it can be difficult to see sometimes in bright day light while pedaling and looking down.

I don’t recommend sticking a finger in the boot.
 
Remove the plug, stick your finger in the plug boot and turn it over, spark is good if you yank your hand away, it's really good if you pee a little bit.(joking)
There was one time my dumb @$$ touched the unprotected top if the spark plug on a running B&S flathead. That was a shocking experience lol
 
My 100cc 2 stroke motorbike has been giving me trouble lately. Before I went and replaced the CDI, ignition coil, and spark plug, it had some occasional difficulty starting up. I figured swapping out these essential parts would sort things out.

Now guess what? No luck. Despite installing them right and connecting the red and blue cables to their appropriate terminals, the bike ain't producing a single spark when I try to fire it up. I mean, come on! I got compression and fuel, so why in hell isn't it working?!

Have any of you dealt with this kind of BS before? Any ideas?
Replace your kill switch, I've had a faulty one already
 
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