The NSU was 500cc and the sidecar had a (I think it was 132lbs) chunk of lead to simulate the passenger. I think it would be more meaningful to test a real sidecar with a passenger. They could specify a weight and use smaller lead weights to adjust the passenger's weight to spec.
So this must have been run on a course with banked turns. In road racing, the passenger moves around quite a bit to keep the center of gravity in the proper location.
My desire to race motorcycles was never very high, particularly after a friend, who crewed for someone, told me the guy came home from one race in a full body cast after breaking many, many bones. It's lower now; at this stage of life, I'm don't want to add any new aches. But the racing job I'd want the least of all is being a sidecar passenger, particularly on right turns.
