I have a vague recollection of what I think must have been the first episode in an animated series that I saw as a kid sometime in the 90s (possibly between 1994 and 1999, although the series might have been created much earlier):
A man who is a citizen of a civilization of humans living in space comes down to earth (on some mission I'm guessing). He was born in space and knows about stuff that occurs on earth (like rain etc.) only through tales the elders have told him. I remember this one particular dialogue where he says when it suddenly starts raining: "Rain... It's just like they told me... like water falling from the sky."
He then goes to a pre-determined location to unpack his transport - a motorbike that assembles itself and sort of 'transforms' form a cube to a complete motorbike. In the same episode another human (but earth-born and not space-born... I think he was a blond guy) finds one of these special motorbikes.
Eventually, I think the two meet up and form a team or something.