  In this letter we show that pseudoscalar meson leptonic decay data can be
used to set stringent limits on the mass $m_{W_R}$ of a right-handed vector
boson, such as the one that appears in left-right symmetric models. We have
shown that for a heavy neutrino with a mass $m_N$ in the range $50<m_N/{\rm
MeV} <1900$ one can constraint $m_{W_R} \lesssim (4-19)$ TeV at 90 % CL. This
provides the most stringent experimental limits on the $W_R$ mass to date.
