They were great days down at the Kingsgrove brickies.
We usually got there on our XR's from Bexley North/Clempton park via the stormwater drain or paddocks adjacent to them, put 50c worth of petrol in at the servo at Kingsgrove, roll down Commercial avenue then give the bikes a rev going between factories (had a cop in a mini cooper waiting for us one day) that led to a path to a gate into the back fence of the pits.
Some guys were lucky enough to live in Glamis street which backed onto the pits and could just go out through their back gate for a ride after school or anytime they liked.
Preferred the free riding (which wasn't really allowed, maybe illegal) on non club days although the club was very well run and organised. I remember they had "officials" scouting the perimeter to keep the non club ferrels away.
Conquering Black mountain hill climb was a big deal at first.
After it was shut down and developed into an industrial area we all just rode at Menai. (still do)
Theres a facebook page with info about a 40 year reunion
http://ozvmx.com/community/index.php?topic=13118.msg129720#msg129720