Turbulent Reynolds, Maxwell, and gravitational stresses at a given radius as a function of time in the CHEM_MHD simulation. Top: at R = 3.1 kpc, which tracks the entire bar region. The oscillations on timescales t ≃ 7 Myr represent a torque-weighted orbital period of clouds orbiting in the bar region (Fig. 27 and recalling that angular momentum is not conserved in a non-axisymmetric bar potential). The overall upward trend is because angular momentum is removed by the bar at a decreasing rate as the gas reservoir that supplies the bar-driven inflow is depleted and the bar-driven inflow stops (Fig. 22 and Sect. 7). Bottom: R = l49 pc, which tracks what happens inside the CMZ gas ring. Maxwell stresses become dominant at t > 200 Myr, and show that magnetic stresses are responsible for the nuclear inflow from the CMZ ring inwards.