Originally Posted by MTBerJim

I think we aren't on the same page and I think I'm about to do you a huge favor.

A UST tire is a normal tire without a tube, in the sense if it gets a puncture it's going to go flat. The product I mentioned was Stan's No Tubes It's a sealant that goes in the UST tire to seal it as a puncture happens, the tire NEVER goes flat.
I've pulled thorns and even a thumb tack out of my tire. It works just as well with non-UST tires, My first set was the tires that came on my bike, I used the Stan's conversion and rode them smooth.

When I replaced them with UST tires I ran my hand inside the old tire and no exaggeration 25 thorns in the back easy.

Never had a flat and you can run lower tire pressures and not have to worry about pinch flats. I was running 25psi upstate NY, rocks roots, big drops--very ugly, ripped a brake line off the rear caliper, but never flatted.

I just went to Stan's site and noticed they have a 700c conversion, that will be on my X-mas list this year.