25yearfan is on the ball, but I believe it was two meetings in 1984, a junior 4TT and the match against Oxford. Birmingham assembled a useful-looking side for the 1985 campaign, but the support was poor in terms of crowd numbers. A pity, given the strong calls for speedway to return to Birmingham both after the demise of Perry Barr and the loss of Bordesley Green. Perhaps many only really supported a return to the north side of the city?
The track at Bordesley Green was excellent, long straights, tight-ish banked corners, and very wide. When it was well-prepared the racing was very good. Sadly, the track was too often a dust bowl, probably an indication of the poor financial state of the club. The inside line was moved in on the corners for the 1986 season, reducing the length of the straights by about 10 metres. However, for one meeting when I think the drainage failed, the former inside line was used.
The "safety" fence consisted of wooden boards hung over the metal crash barrier. I always thought this was a serious fault, and I recall Paul Evitts and (I think) Chris Pidcock injuring themselves colliding with the fence.
The track was tarmaced and now stages car racing, often to crowds no bigger than the speedway used to attract.
The Midlands used to be a speedway hotbed. I once did three meetings at different tracks in one day, at Cradley, Bordesley Green and Wolves. It'd be virtually impossible to do that anywhere in Britain now.