She's tucked the dress up a bit, and not really hanging off. A swinger on a speedway chair will be touching the ground and have tyre marks on their back from a bike on the inside. Speedway sidecars is one of the most exciting and physical motorsports there is, these guys (and girls) give no quarter, real tough racing. I've been watching it since my teens, and this is a clip from our local track when I lived in Auckland. Racing on saturday night at the big track, then sundays down here. Late 20th and early 21st Century I'd be on those seats at the start line, having a beer with my mates from the '70's. I even have a photo of me out there in the '70's doing a bit of flattrack.
But this earlier stuff is more how I remember it to be.