‘BuddyPress forums’ is bbPress (as far as i know)!
bbPress is a separate plugin – bbpress.org. We have the BuddyPress 1.6.5 forums on our site without the bbpress plugin installed, and they seem very dated IMO.
It would be nice to have this all explained in one definitive document though, as we’re not clear what we have to do to maintain the most up-to-date forums.
it is in the Codex!
Originally BP used a stripped down version of bbpress built in, now that is removed and bbPress plugin provides support for BP groups forums, there is a guide on transitioning over.
https://codex.buddypress.org/user/buddypress-site-administration/migrating-from-old-forums-to-bbpress-2/
Ah yes, my bad. BP forums was pre 1.6.5. The bbPress plugin is different.
This may help you move everything across:
https://codex.buddypress.org/user/buddypress-site-administration/migrating-from-old-forums-to-bbpress-2/
Thanks guys! Ah, here it is: https://codex.buddypress.org/developer/releases/version-1-7/
Forums
Retired bbPress 1.x “Group Forums” component (replaced with bbPress 2.x integration) (#3598)