This is not a video about small chicken hamburgers but perhaps flat track purists should stop reading/watching now!
Dirt track, as it's known Down Under (Australia), is a little different to what is traditionally seen as 'Flat Track' but the gist is basically the same.
Flat dirt track (mostly), very enthusiastic, competitive riders and a small loyal crowd.
This is the 1982 'King of Nepean' race series, the video gets interesting about one minute in when two sliders (grasstrackers) start dueling with a chook chaser (Aussie slang for MX bikes). It's worth watching just to hear a horse racing commentator call a motorcycle race (his after race comment is a keeper). It's a good race!
Back then Nepean Raceway [the closest dirt track to Sydney] was prepped with waste oil to give a slick but tacky surface and to keep the dust down. It's one of a handful of race tracks still operating in New South Wales Australia.
NOTE - See what's being raced at Nepean now in Sideburn 24.