In a beginners group at a track day- any bike will do. The pace allows for everyone to learn the limes and braking points and it's not competitive by any means, overtaking is prohibited in most cases.
Same in the intermediate although the pace will be significantly quicker.
The pace of the blue groups at TTD around here will demand a lightweight bike though, and with proper track set up. You will also need slicks, properly dialed (and resprung) suspension and some of those Vesrah rjls.
There are some videos around from fast tracks with gen2 Busa tearing it up,
but nothing that a 1000 can't do.