  Axigluons are colored heavy neutral gauge boson that couple to quarks through
an axial vector current and the same strong coupling as gluons. The most
important model-independent manifestation of axigluons is the generation of a
forward--backward asymmetry in top-antitop quark production at $p\bar{p}$
collisions which originates from the charge asymmetry. We update our previous
analysis for the inclusive QCD induced forward--backward asymmetry and define a
new observable which is more sensitive to the effect than the forward--backward
asymmetry. Furthermore, we find a lower limit of 1.2 TeV at 90% C.L. on the
axigluon mass from recent measurements of the asymmetry at Tevatron. Also at
LHC, the charge asymmetry is sizable in suitably selected samples. We evaluate
this asymmetry in the central region for different selection cuts and show
that, like at Tevatron, the charge asymmetry can probe larger values of the
axigluon mass than the dijet mass distribution.
