Small Engines (Lawn Mowers, etc.): kaw fc420, regulator rectifier, safety module

Question
I'm not fetting any spark. Any idea where to begin? I'm a bit of a novice. When i pulled the plug and held it with the wire against metal there was no spark ?Help

Answer
first check for a sheared flywheel key.  Next check to be sure the system is grounded.  Then it is either the regulator/rectifier or CD coil.  The other thing is what it attached to.  Is there an operator presents control that could be faulty or a bad safety module.