1983 Namur 500GP...
the actual race doesn't start till the 25:55 mark....the 1st 25 minutes is talking to riders, weighing the bikes, watching some practice/qualifying laps, and some great sounds of 500's on the pipe...but still all good stuff and cool to watch, not entirely in English either...
https://www.youtube.com/watch?v=4PdNnZzG7h4