Since mine are 12/13 years old I wonder if there is something like a tension washer to make them slow down that is worn. When I stopped the spinning there was a little resistance or braking in some spots to hold but, wasn't enough to hold.
I think HappiJack Corporation needs to machine the threading not so steep but they already operate slow enough. Or perhaps a governor brake. I don't know enough about it. All I know is they spun down like they were well lubed. It was the 2 front ones that acted like this.
