The power spectra of magnetic fluctuations occurring close to the ramp of the quasi-perpendicular, low-&bgr; bow shock indicate the presence of obliquely propagating electromagnetic waves with frequencies above the ion cyclotron frequency, &OHgr;i. These waves appear to be associated with ion distributions consisting of a bi-Maxwellian core and an energetic, approximately gyrotropic ring. We investigate the generation of ion cyclotron waves by distributions of this type, using particle and wave data from the AMPTE/IRM spacecraft. In the case of a monoenergetic ring, instability is possible over a broad range of frequencies &ohgr;>&OHgr;i, with the highest growth rates occurring at propagation angles of typically 50¿--80¿. As the velocity spread of the ring vr increases, the growth rate of perpendicular-propagating waves falls, complete stabilization occurring when vr is greater than about 20% of the mean ring speed u. The parallel-propagating Alfv¿n ion cyclotron mode can be excited if the core is anisotropic, with T⊥≂3T∥. The maximum growth rate is obtained when vr is comparable to the core ion parallel thermal speed. However, if vr≪ u, the growth rate is much smaller than &OHgr;i. Using these results, we show that certain qualitative features of the AMPTE/IRM wave data can be understood in terms of a nearly monoenergetic ion ring beam at the shock ramp, evolving into an extended ring beam, and then merging with a quasi-bi-Maxwellian ion core as it moves downstream. ¿ American Geophysical Union 1993