  Following a glitch, the crust and magnetized plasma in the outer core of a
neutron star are believed to rapidly establish a state of co-rotation within a
few seconds by process analogous to classical Ekman pumping. However, in ideal
magnetohydrodynamics, a final state of co-rotation is inconsistent with
conservation of energy of the system. We demonstrate that, after the Ekman-like
spin up is completed, magneto-inertial waves continue to propagate throughout
the star, exciting torsional oscillations in the crust and plasma. The crust
oscillation is irregular and quasi-periodic, with a dominant frequency of the
order of seconds. Crust oscillations commence after an Alfv\'en crossing time,
approximately half a minute at the magnetic pole, and are subsequently damped
by the electron viscosity over approximately an hour. In rapidly rotating
stars, the magneto-inertial spectrum in the core approaches a continuum, and
crust oscillations are damped by resonant absorption analogous to
quasi-periodic oscillations in magnetars. The oscillations predicted are
unlikely to be observed in timing data from existing radio telescopes, but may
be visible to next generation telescope arrays.
