“Shut up Sharon, I think that Starbucks is just right around the corner here…”

It lighter than a tube on a dirtbike. It makes the rotating mass less.

On a mountain bike the amount of material you’d need would definitely be a little bit of added weight vs tubeless. But it probably wouldn’t be a whole lot more substantial than tires full of sealant. Certainly wouldn’t be any more than these doubledown sidewall tires, which would be substantially heavier. The only way they fail is if the tire fully comes off the bead. We use rim locks on dirtbikes to prevent that, but dirtbikes also weight 250 pounds, and they produce a lot of power under throttle. You wouldn’t need that with a mountain bike tire.

It would beat flat tires trailside, having to constantly reinflate a tire that’s been sitting, and it would eliminate the mess of sealant.

Yep. I use inserts on my on road car rc racing car too.

So faster, heavier, more powerful, but the comparison isnt useful?

Just so we are clear, I don’t have any air in my tire. No tubes, no messy sealant, no tubeless. It’s a foam core. It can’t go flat, and you get traction for days. It’s not cush core, or any of the alternatives, which is where I think they went wrong, because those all still require air. Air is one of the biggest, if not the biggest failure on a mountain bike. They don’t weight all that much either, I’d take an extra few ounces of rotating weight vs futzing with air trailside.

He’d like em a lot better, if he took the tread off and stuffed them inside a tire. Still wonder to this day how mountain biking hasn’t picked up on Mousses. They came pretty close with those cush cores, but they still weren’t really meant to be run flat. I run mousses in my dirtbike, and they generally kick ass. A big miserable to install the first couple times until you get the hang of it, but awesome.

I generally like traction.