Panel a: Ω_spin/Ω_bin as a function of the semi-major axis at the time the AGB star has stellar parameters as in Table 1. The coloured lines represent different mass ratios. The region where the vertical lines start corresponds to orbital separations for which the binary system had gone into a common envelope at the time we computed the binary parameters. Panel b: maximum Ω_spin/Ω_bin as a function of the initial orbital separation of the system. Colours represent equivalent mass ratios.