my moped runs fine on ac. yep, alternating current. how does it start? well ... my moPED has pedals ... so i pedal to get the flywheel spinning ... which generates electricity ... which fires my sparkplug ... wow! my moped runs.
oh ... and my electrical system is grounded. i have a wire that is strictly for "ground" and it bolts to the left side of my bike under the foot cover. if it touch it ... my hand feels a sharp pain. ouch! ... ac hurts!