James wrote:

How do I erase a performance recording in pattern mode on the Motif XF 8.

You can "Clear" a single Track of your Pattern or you can "Clear" all the Tracks. Performance Record directs the four Parts of the Performance to Tracks 1-4 of the selected target Pattern and Section. It also can COPY the Performance Parameters to the first four Parts of the MIXING Program associated with target Pattern.

Step-by-Step for Clearing Pattern Tracks
Press [JOB]
Press [F5] TRACK
Select the Job 04: Clear Track
The dialog box will automatically populate with the current Pattern Section, for example Section = A; Set the Track = all
Use the DATA DIAL fully clockwise to select Track = all
The dialog box allows to select which attributes you'd like to clear... Default is Seq Events, Play Effects, Mix Part Parameters
Press [ENTER] then [YES] to execute
"Completed" will appear.

Done.

There's also a potentially confusing difference in a Pattern between Tracks and Phrases, and the potential for "hanging Phrases" (i.e. Phrases that are not associated with any Track).

If I'm remembering right, this was something that Bad Mister helped me with a while ago over at motifator.com.