Id have a look at the softwheel with 20” rims and fat wheeltires

This a wheel from a wheelchair, but the system could be built, I believe, for those 20” fatwheels too.

We had discussed about stronger tires for the Max up-thread. I recently ordered the tires shown below, (through David Cooper) from Azusa. Not put them on the plane yet. As the tire walls are thicker, there may be a slight reduction in damping effect on landing, even if we keep same 8 PSI inflation. But worth trying out.

Fits on the standard 6 inch plastic wheels from Azusa. They weigh 2 lbs each ( just the tire, tube and rim are extra )
The ribbed wheel barrow tire weighs 1.3 lbs each. So that makes a net addition of 1.4 lbs to total weight. These are also wheel barrow tires ( tube type ) not fit for highway use. These have a 4 ply rating (as stamped on the tires) with Max inflation 50 PSI. ( The ribbed tires had a 2 PR with 30 PSI max.)

These are about $20.00 per tire plus about $20.00 shipping for 2 tires.

I lifted the following paragraph from another forum.
There is a separate link further below for ac tires.
Nothing new, most builders already are aware.

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Q: What does PR stand for in tire size?


Answer:

PR= Ply Rating.
8 PR means the tire has the strength equal to a tire with 8 ply's of cord in the body of the tire. The newer term for the same thing is load range. The PR is a hold over from the early days of pneumatic tires, when the only way to make one stronger, or support more weight was to add another layer of cord. Not sure what they used in those days, but let's just say it was cotton.

When stronger cords (nylon, rayon, whatever) were developed, they could make a tire with, say 4 layers of cord that would be equal to 8 layers of the older cord material. So that tire would have a 8PR although it only had 4 ply's. Most car and light truck tires now use the load range system to indicate the strength of the tire. Not sure, but I think that all on-highway tires use load range letters to comply with a DOT standard.

The short answer is, PR is a measure of the strength, or load carrying capacity of the tire.

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AOPA link for AC tires:

https://www.aopa.org/news-and-media/all-news/2013/april/15/whats-so-special-about-aircraft-tires

I installed the tires with thicker wall, and so far in taxiing and a couple of crow hops, they have been very suitable for the MiniMax 103. They do flex nearly like the ribbed wheel barrow tires at 8 PSI inflation. Not had any flats after installing them.

Bumped for reference to a question.