We have surveyed the risetimes of all E>15 MeV solar energetic proton (SEP) events observed on the NOAA GOES spacecraft between 1984 and 1989 and associated with well-connected (W20--W70) solar flares. Twelve events occurred during the times of observation by the coronagraph on the SMM spacecraft, and each event was associated with a coronal mass ejection (CME) observed above the west limb. In each of the three SEP events with the longest flux risetimes a second CME was observed before the time of peak flux. While all the initial CMEs were associated with prominent solar flares, the subsequent CMEs were not accompanied by obvious X ray or ratio bursts. We interpret the long risetimes of two of the three SEP events in terms of a second SEP injection due to the second CME. ¿ American Geophysical Union 1993