Relativistic nonlinear models in the Hartree-Fock approach, with σ, ω, ρ and π mesons, are used to explore the influence of the nucleon-nucleon tensor force (tf) on the behaviour of the nuclear charge radii of the Pb isotopic chain. It is found that a part of its effect on the charge radii is channelled through its opposite effect to the spin-orbit interaction. The kink effect seems to be produced by the combination of the geometrical features of the 1i11/2 neutron orbital and its binding energy.