  In this work, we explore new spin-1 states with axial couplings to the
standard model fermions. We develop a data-driven method to estimate their
hadronic decay rates based on data from $\tau$ decays and using SU(3)$_{\rm
flavor}$ symmetry. We derive the current and future experimental constraints
for several benchmark models. Our framework is generic and can be used for
models with arbitrary vectorial and axial couplings to quarks. We have made our
calculations publicly available by incorporating them into the DarkCast
package, see https://gitlab.com/darkcast/releases.
