B decays to Charmonia at LHCb

The LHCb experiment is a forward arm spectrometer designed to make high precision measurements of b hadron decays at the LHC. During 2011 a total luminosity of 1.0 fb$^{-1}$ of data was collected at $\sqrt{s}$=7 TeV. LHCb's efficient dimuon trigger allows to perform studies of B mesons decaying to charmonia with high precision. We will present results on B decays into $J/\psi$ and light hadrons, together with measurements of the relative branching ratios of exclusive b decays to final states involving $J/\psi$ and $\psi(2S)$ mesons.