OK, here's what I found. I too was pulled over in Largo, Fl. (thankfully I work for the City) and told the Attorney General had weighed in and made his decision that gasoline, motor-assisted bicycles were all the way around were illegal.
Basically, Chapter 316.003(2) defines a bicycle as every vehicle propelled soley by human power OR human power and an electric helper motor capable of no more than 20 mph, blah, blah, blah.
However. Chapter 316.003(77) defines a MOPED as any vehicle with pedals to permit propulsion by human power,.... with a motor rated at less than 2 brake horsepower and not capable of more than 30 mph on level ground; and with a power-drive system that functions directly or automatically without clutching or shifting gears by the operator AFTER the drive system is engaged. If an internal combustion engine is used, the displacement may not exceed 50 cubic centimeters.
In a nutshell, to operate at this level of craziness, we are classified as "mopeds" and must obey all traffic laws applicable to a human powered bicyclist, furthermore, if we intend to operate our bikes after the State recognized time of "Sunset," we must also install front and rear reflective devices, headlight and tail/brake lights.
Also see 316.008, 111, 320, 322, 324, and Advisory Legal Opinion 77-84
Hope this helps.