Re: Good solid runner till the other day...
Welcome, you've come to the right place. There is a wealth of good information and experience here to help you.
Water in the magneto is not a good thing. Did you get caught in the rain...wash your bike? The most common entry point is where the wires exit the engine case near the front. Moisture can ground out the magneto and cause the problem you're describing.
You can try spraying the mag with WD-40, blow dry and let air dry for a few hours but there is a chance the coil is soaked and will require more drying time. Many of us seal the wire exit hole with a good silicone gasket sealer such as Permatex Black Silicone. After trying that and if you still have no spark you might be faced with replacing the nagneto coil. Did the CDI get wet too?
There are several things that could be wrong. You said you have checked spark but how did you confirm that the plug is firing? Give us a little more information and we'll be here with help. I assume you have a Chinese 2 stroke motor? Come back with a little more details.
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