Essence, friend Alex. Many things must evolve to return to their essence, to their origin, society has the perception of technology without thinking that not everything modern is better than the original.
The bicycle does not escape, being its origin the transport without energy, its benefit to keep us healthy in its practice, to install an engine is to change it completely, do not worry the same man who today invents a machine in a while will make it again original.
Regards !!