  Decay rate, forward-backward asymmetry and polarization asymmetries of final
state leptons in B-> K_{1}tau ^{+}tau ^{-}, where K_{1} is the axial vector
meson, are calculated in Standard Model and in the universal extra dimension
(UED) model. The sensitivity of the observables on the compactification radius
$R$, the only unknown paramter in UED model, is studied. Finally, the helicity
fractions of the final state K_{1} are calculated and their dependence on the
compactification radius is discussed. This analysis of helicity fraction is
briefly extended to B->K^{*}l ^{+}l ^{-}(l =e,mu) and compared with the other
approaches exist in the literature
