I heard rumors of beam.ride, beam.fly, etc on their Reddit. Not sure if those would be DLC or separate games.
But there already is airplanes in BeamNG drive and there is a (soso) bike already in drive too. And I thought they said no people?
That is also possible with motorcycles lel. But even if it would need a rider? Wouldnt hurt would it? There are mods where cars have a crash test dummy on them so why not on motorcycles?
I stay away from Reddit so I don't know what's there, but I know they have commented about making other games with this engine in the fairly distant future, and if I understand their older statements, there won't be paid DLC for this game. (I can't imagine the BeamNG team doing paid DLC at all though, even in a future project...)