Bike won't start. Help!

unhook kill switch, hook blue to blue, black to black, unhook white if it is there

check for spark

check spark wire is screwed on tight at each end, check for 320-360ohms on the blue wire coming out of motor to ground

These 2 strokes aren't hard to diagnose. Start with figuring out what the problem is. It takes Fuel and fire to make it happen. So, start with the easy stuff. Spray some WD-40 and starter fluid (spray a little of each) in the spark plug hole. Now, pedal your butt off, and release the clutch. If you get a little chug or if it runs for a bit, then you're not getting fuel, and it's your carb not getting fuel/giving fuel. If you don't get a chug, then removed (and replace) your spart plug. If you have a harbor freight and get a spark plug tester. Usually a new spark plug will fix some problems. The magneto is easy to change and the CDI is easier to change. All these parts are very cheap. So, just take your time to diagnose, and it'll be easy for you to fix once you remove things out of each equation.