The effect of plasma density on toroidal rotation was examined in density ramp-up experiments at a plasma current of 1 MA and a toroidal magnetic field of 3.6 T in Tore Supra ohmic discharges. Experimental measurements have shown that the toroidal rotation amplitude is reduced at all radii when increasing the plasma density, although it remains in the counter-current direction. Neoclassical predictions including ripple-induced toroidal friction are in qualitative agreement with such observations. However, in the core (r/a < 0.5) the plasma accelerates at nl ∼ 3 × 1019 m−2 and breaks again above nl ∼ 3.5 × 1019 m−2. This rotation bifurcation did not appear to be correlated to a possible influence of the sawtooth activity. Nonetheless, quasi-linear gyrokinetic simulations have shown that the transition of the nature of linear microinstabilities from ITG-TEM to pure ITG occurs at nl ∼ 3 × 1019 m−2, which could indicate a change on the turbulence driven contributions and explain the deviation from neoclassical predictions in the plasma core.