To remove timestamp labels and/or category lables from your RSS feed please do the following:

Login to calendar as administrator -> Go to Admin Menu -> iCal and RSS Feeds -> RSS Tab -> Deselect the "Date and Time Stamp (sortable)" and/or "Event Category Name" under the prepend options -> SAVE

If you have the RSS feed embedded into your website, refresh your browser to view the change to the RSS feed.  If you are using a RSS widget or website plugin, there may be a slight delay in seeing the change take effect, since the change will depend on how frequently your website freshes the RSS feed.