Did the coil come with a new spark plug lead. If not and you had to screw the old one in then the spark plug end of the wire may bed bad. Cut off about a half inch and reinstall the plug boot. A bad ground for the coil is possible. Kill switch malfunction........disconnect it to test. Weak stator. Pulse Generator if it is separate from the stator. Loose or worn wires and connections.
Why replace spark plug and other related parts wirhout testing pickups and stator first? Thats number one, spark starts at the source. Work from the source, not the finish line. Look for pretty much any voltage from the pickups and test the stator leads for grounding.