  We discuss the spin evolution of pulsars in the case where a superfluid
component of the star is coupled to the observable crust on long, spindown
timescales. The momentum transfer from the superfluid interior results in an
apparent decay of the external torque and, after a dramatic increase, to an
asymptotic decrease of the generic value of the braking index, e.g. $n=3$, to
values $n\sim 2.5$ if the magnetic field of the star does not decay over its
lifetime. In the case where an exponential decay of the magnetic field towards
a residual value occurs, the star undergoes a spin-up phase after which it
could emerge in the millisecond sector of the $P$-$\dot P$ diagram.
