As you can see in the video attached, I was riding in the mountains, got off the motorcycle, launched into the air, and died.

This also happened to me a few months ago on the stable version with a car, and it was on a hill too.

1. For the motorbike, park side-on on an inclined. For the car do the same as the motorbike but you have to get on the seats facing down the slope.

2. Get out of the vehicle and fly.