Yes, quite sometime ago I had my bike on the back and a full tank of water which then made the tongue
light. Everything was fine until I was going too fast, down a hill and picking up speed when I hit a little bump. That's all it took. Scared me to death so I now watch my speed, never go over 60mph. I added an anti sway bar just 'cause.
Now, I've had the
generator on the tongue for several years which fully compensates for the
weight of bike and full water tank. The trailer is well balanced and there is no need for the anti sway bar but I still use it.