To test your spark, pull the plug out and use a clamp of some kind to hold it to the cylinder head, and then have someone pedal it. Do NOT hold the plug over the plug hole as gas could come out of the spark plug hole and catch the charge from the spark plug on fire. If you aren't getting spark, you could bypass the main wiring harness and ground the points, and hook your positive to the coil. This will tell you that there is a problem with the wiring also, and rule out the magneto. Or even check Fred's guide on this website for helpful information.