Ecosse, the second pic says Derbi, good chance it is..
first pic, I say Royal Enfield FLYING Flea...
built like a gun, I bet.
I know nothing about futuristic bikes on Tron, only the pic I saw here.
I do know they used a few Ducatis in the flick, and /or what looked like Dicatis in the stunts..
Come visit and we can show you..
The Ram jet bike, You would think the guy would maybe run a real early Schwinn springer, not that tin latestyle cheapo..