Rotation velocity profiles for the FRs with highest number of tracers along the major axis. The full circles show the fitted amplitude V_maj.ax. on the PN velocity fields (see Eq. (12)). The red stars are stellar kinematics along the photometric major axis from the literature (references in Table 1). The PN kinematics of NGC 4594 is compared with the stellar kinematics from a slit parallel to the major axis, offset by 30 arcsec (purple stars). The orange vertical lines mark the sizes of the photometric disks (see text). NGC 4494 shows a decrease in V_maj.ax. but there is no photometric evidence for a stellar disk. When the disk fades in the slowly rotating spheroid, the rotation velocity decreases. In addition, the PN rotation velocity may be lower than the values from absorption line spectroscopy at the same radii because of the smoothing that averages disk and spheroid PNe for near edge-on disks.