Hello Dustydog, I think that, in most cases to get the wheel high enough to be up inside the A frame, or flat against the chassis, the wheel must be up inside the cutouts that I mentioned, and once in this position an be considered locked in. I had a jockey wheel slip out of the holding clamp once, and suddenly heard a high pitched whine from the rear of the car, which was the inflatable tyre zipping along at about 60 mph! Since then I have always double checked that I have done up the clamp tightly. Beware good intentioned helpers when hitching up !!! Another time I was on a dual carriageway with another outfit in front and we could see that his jockey wheel had dropped onto the road. When safe to do so I flagged him down and found the jockey wheel all intact, but slightly bent. The windinghandle was ( I think) slightly loose ,, but the driver admitted he knew nothing about the slot cut outs and had just wound up the wheel to where he thought was "ok", and so with vibration and wind pressure we assumed the wheel had been turning around and lowered itself. I would have thought that if the jockey wheel is lowered by any other means than the handle it would have the effect of leaving the handle loose?