  We study spin effects of quantum wires formed in bilayer graphene by
electrostatic confinement. With a proper choice of the confinement direction,
we show that in the presence of magnetic field, spin-orbit interaction induced
by curvature, and intervalley scattering, bound states emerge that are helical.
The localization length of these helical states can be modulated by the gate
voltage which enables the control of the tunnel coupling between two parallel
wires. Allowing for proximity effect via an s-wave superconductor, we show that
the helical modes give rise to Majorana fermions in bilayer graphene.
