Self running, perpetual bike; does it really work?

This recreation of the "perpetual" bike shows how easy it is to fake perpetual motion!

If you pay very close attention, you may be able to tell that the board is being ever so slightly tilted back and forth to maintain a downward gradient for the bike to roll down.

See original "self running" bike here:

[scircuitcitadel]

it's working! then how ua saying it's impossible?