  With this work we investigate an often neglected aspect of Brownian motor
transport: The r\^{o}le of fluctuations of the noise-induced current and its
consequences for the efficiency of rectifying noise. In doing so, we consider a
Brownian inertial motor that is driven by an unbiased monochromatic,
time-periodic force and thermal noise. Typically, we find that the asymptotic,
time- and noise-averaged transport velocities are small, possessing rather
broad velocity fluctuations. This implies a corresponding poor performance for
the rectification power. However, for tailored profiles of the ratchet
potential and appropriate drive parameters, we can identify a drastic
enhancement of the rectification efficiency. This regime is marked by
persistent, uni-directional motion of the Brownian motor with few back-turns,
only. The corresponding asymmetric velocity distribution is then rather narrow,
with a support that predominantly favors only one sign for the velocity.
