The door and hinges over the filler cap has to cost something. Eliminate the cost of the door and put the filler under the trunk lid at the far end of the Elio. That way it's on neither side but in the middle like the typical motorcycle. Park on either side of the pump. I assume the cap is non-venting. The VW Bug had it's filler under the front hood, prevented gas being stolen.
I think they said Elio will use a gas capless system
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