A dedicated campaign has been run on JET to study the effect of Toroidal Field (TF) ripple on plasma performance. Radial electric field measurements from experiments on a series of plasmas with internal transport barriers and different levels of ripple amplitude are presented. They have been calculated from charge exchange measurements of impurity ion temperature, density and rotation velocity profiles, using the force balance equation. The ion temperature and toroidal and poloidal rotation velocities are compared in plasmas with both reversed and optimised magnetic shear profile. Poloidal rotation velocity (vθ) in the ITB region is measured to be of the order of a few tens of km/s, significantly larger than the neoclassical predictions. Increasing levels of TF ripple are found to decrease the ITB strength and maximum value of vθ. The poloidal rotation term dominates in the calculations of the total radial electric field (Er) and E×B shearing rate, with the largest gradient in Er measured in the radial region coinciding with the ITB.