I picked a date at random, 27th Nov 2002 and then just clicked the forum link at the top of the page (just like in the old days)
http://web.archive.org/web/20021202205252/www.robotwars.co.uk/forum/http://web.archive.org/web/20021202205252/www.robotwars.co.uk/forum/http://web.archive.org/web/20021202205252/www.robotwars.co.uk/forum/http://web.archive.org/web/200212022...s.co.uk/forum/

Ive tried a couple of other links, but think I must have been lucky with my choice of date as most seem to have path errors