Sick Dirtbags

[Big RR]

I recall buying them at tire stores, and many times all I could find were car tire tubes (even though there were tubeless tires on most cars then, using a tube was common to extend the "life" of worn out tires (you do what you have to in high school).

[rubato]

Since an inflated tire inner tube will easily keep a 200+ pound person afloat, I doubt the composition of the wheel makes a difference unless it and the tire together are well over that weight.

Wha! Would you like an opportunity to examine and re-word that? The net weight of the tire + wheel are immaterial. What matters is the difference in density of the net tire, wheel, enclosed airspace and the density of the body of water (salt water is more dense) and the volume. There is usually a steel belt and wires which support the 'bead' which offsets any buoyancy due to the tire material. Modern low-profile tires have even less airspace to offset the greater density.

yrs,
rubato

[rubato]

I recall buying them at tire stores, and many times all I could find were car tire tubes (even though there were tubeless tires on most cars then, using a tube was common to extend the "life" of worn out tires (you do what you have to in high school).

Tubes used to be used as a 'cheap fix' for certain punctures but they don't do anything to extend tread wear.


yrs,
rubato

[Big RR]

No, but what they did is allow you to still use a tire that had worn through, especially in sidewalls (which often were thinner than the tire tread surface). I can't tell you how many times I drove on tires where the cords showed through--if it was only a little crack, a tube would allow it to continue to be used, albeit unsafely.