One motorcycle tire. Caster solved.
One air ram. Ground pressure/high speed solved.
two hydraulic, center returning, properly tuned shocks. Turning solved.
Batteries on or off? User discretion based on needs. No need to debate semantics, we all have different needs and wants. Both have ups and downs.
If on: would need a suspension to deal with the added weight, otherwise you'll be wearing out the tire system quickly. Would also make ditching your "trailer" simple, an easy way to drop weight, all of it.
If off: Trailer is easier to control, less mass pushing you, more mass over the truck's wheels. Tight turns wouldn't force a jack-knifing.
There are so many variables it's stupid to discredit one person's ideas. What works for you fails for me. I would never do this, I take my truck over pot holes knowing it'll soak it up without bottoming out or up. It's a truck. It goes offroad. The roads here are abusive. A system like this wouldn't last a year. It'd be pointless in the winter (parts at least). Etc, etc. Frank, Christ, stop arguing over who's right. You both are.
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