  We consider an extension of the standard electroweak theory with gauge group
$SU(2)_L \times SU(2)_R \times U(1)_{\tilde{Y}}$, where the gauge bosons of the
extra $SU(2)_R$ factor do not couple to ordinary fermions. We show that
precision electroweak data and flavour physics provide quite stringent indirect
constraints on its parameter space, but still allow for relatively light
non-standard gauge and Higgs bosons. We then consider the model phenomenology
at high-energy colliders, and observe that in the gauge boson sector present
bounds and possible future signals are dominated by $Z'$ production. In
summary, indirect constraints on the charged gauge boson sector are so tight
that observable new effects must be connected either with the neutral gauge
boson sector or with the extended Higgs sector of the model.
