bbPress.org

well its not really a limit on having a certain number of forums
i think its just a limit of it being on the root page since it doesn’t have pagination.

for example if you have over 50 forums displayed in the forum root page any additional forum will not display

i found this function doing a search , i havent tested though.

plop the code into your child themes functions.php file or your functionality plugin
and change 100 to whatever you like

function bbp_increase-forum-per-page( $args = array() ) {
$args['posts_per_page'] = get_option( ‘_bbp_forums_per_page’, 100 );
return $args;
}
add_filter( ‘bbp_before_has_forums_parse_args’, ‘bbp_increase-forum-per-page’ );

code is from this topic

Hitting 50 forum limit? What can I do?