2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/6846I discuss measurements of disk mass from non-circular streaming motions of gas in the barred galaxies NGC 3095 and NGC 4123. In these galaxies with strong shocks and non-circular motions, the inner regions must be disk-dominated to reproduce the shocks. This requires dark matter halos of low central density and low concentration, compared to LCDM halo predictions. In addition, the baryonic collapse to a disk should have compressed the halo and increased the dark matter density, which sharpens the disagreement. One possible resolution is a substantial amount of angular momentum transfer from disk to halo, but this is not particularly attractive nor elegant.6 pages, 4 figures, to appear in the proceedings of IAU Symposium 220, "Dark matter in galaxies", Sydney, July 2003, eds. S. Ryder, D.J. Pisano, M. Walker and K. FreemanAstrophysicstext