[CeeforCitroen]

That setup with the golf cart motor looks cool - driving a back axle. Does each have an independent freewheel? A free wheel is mandatory (unless it's a central hub motor) or else the motor will probably be destroyed spinning several times its rating when driving 60+ mph. Also, the moving parts would sap more energy than you'd save.

Of course my car has no official back axle in the driving sense. It is just a cross bar to strengthen the back and is not even in line with the centre of the wheels. The wheel hubs on the back just free wheel independently, though are obviously connected to the braking gear and bearings. I have no drive shaft that I can apply power through.

As for being the most efficient on the forum - I think a solar e-streamlined-shell- recumbent would be the most efficient. A weird quirk is that e-bikes are lower carbon emissions than pedal power. First of all, human muscles are about 25% efficient e.g. similar to an internal combustion engine (against the 60-90% efficiency of an electric motor). Unless the other person is eating anyway and letting themselves get fat - until the extra energy use of daily activities surpasses the cyclist. Cycling would use extra food, by the time you've farmed the food, packaged the food, kept the food cold in store fridges (Though refrigeration is going to be an energy cost anyway, I've been in one where all the open fridges were enough to provide AC for the store! Assuming the heat from the back was vented outside), bought the food, processed the food, cooked the food, washed the dishes, showered your increasingly sweaty body more often than you'd otherwise have to, washed your sweaty clothes more often than you'd have to, then the electric wins by a large milestone. Though it likely still beats the car by a large margin. Unless you are a raw vegan who eats home grown food and takes cold showers.