Strange little clip from a 1965 movie "Spring Night Summer Night". It's an R50 or R60...don't think it's an R69S. The bike seems to have some get up and go...the driver is really carving up this dirt road, too. From the discussion I was reading about this, it seems clear that the sound heard from the mufflers is likely dubbed in during post production.
https://youtu.be/KMgzNBmPqpQ
https://youtu.be/KMgzNBmPqpQ