  Investigations on the solar cycle variation of the properties of suprathermal
populations (H and other heavy ions like $^4$He, $^3$He, C, O and Fe) in the
solar wind are sparse and hence, poorly understood. In the present
investigation, solar cycle variations of "quiet" time suprathermal elements are
investigated using $<$ $\sim$ 1 MeV/n particle flux data obtained from
Ultra-Low Energy Isotope Spectrometer on board Advanced Composition Explorer
satellite during the solar cycle 23 and 24. The analysis reveals that helium
($^4$He) shows zero or positive lags with respect to sunspot numbers in solar
cycle 23 while it shows zero or negative lag in solar cycle 24. On the
contrary, although iron (Fe) shows zero or positive lag in cycle 23 similar to
$^4$He, it shows only zero lag in cycle 24 and no negative lag is seen.
Further, significant differences in the spectral indices are seen between
$^4$He and Fe in cycle 24 compared to the cycle 23. These results suggest that
generation mechanisms responsible for suprathermal $^4$He and Fe underwent
changes in cycle 24 and these mechanisms are probably dependent on the first
ionization potential and mass to charge ratio. This proposition gets credence
from the fact that changes in the lag and spectral slopes for C and O are not
significantly different in cycle 23 and 24.
