I'm watching E.T. The Extra-Terrestrial on TV right now. I felt the urge to post this.
In Star Wars: The Phantom Menace during a scene with the senate arguing and the camera going to different parts of the senate, one of the species of aliens that's showed was ET. You can then assume that since ET's are in Star Wars then ET The extraterrestrial movie exists in the same universe as Star Wars. In one scene (in ET's movie) the young girl dresses ET up in a halloween costume and goes trick or treating. ET doesn't react to any of the kids dressed up except for one: a kid dressed as Yoda. Why? because ET recognizes him.
How does he know Yoda? ET is a Jedi. This would explain how ET made the bikes fly ...he used the force.