In your video when you are slowly pulling the recoil, the armature plate is moving which might be from a coil heel sticking out too far and catching the inside of the flywheel. That in turn may be causing the armature plate to move and lower the throttle, to the point it won’t idle. The coil hitting could possibly be the source of the knocking. And maybe it’s running a little rich, so once you can get it running for any length of time try dialing in the carb needles a little leaner, high speed first then low speed. Can’t get it perfect in the bucket but it might help it idle a little better and smoke less.
