  The simultaneous presence of both the so-called `ultra-fast rotators' and
slowly rotating stars among the solar-type stars ($\sim 0.6-1.2 M_{\odot}$) in
the same young star clusters has been a puzzle in the field of stellar
rotation. No model to date has been able to explain both by a single mechanism
intrinsic to the star and questions about the appropriate initial conditions
for models often complicate the problem.
  In this paper, using the same starting conditions for the models that we used
in examining the origin of the ultra-fast rotators in young star clusters, we
show that the slowest rotators demand an extrinsic mechanism. Assuming that
this mechanism is a disk-star interaction, we determine that a disk-locking
timescale of a few Myr must operate for this type of star. If, instead of
allowing (radial) differential rotation, we enforce solid-body rotation, the
models require timescales about two to three times as long.
