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Comment by bufferoverflow | Hacker News Reader

How do they deal with rocks/mud/dirt/sand getting inside?

I suspect the production version will have a covering on the sidewall for that and to reduce aerodynamic drag. It won’t be structural like current tires but I think the “wall-free” design you see now is Just prototype marketing.

That will interfere with cooling. Heat buildup will reduce lifespan.

This was researched and practiced since at least first world war, with pioneering applications dating to 1850s.

TLDR: internal friction in the rubber kills it. Acceptable for military and heavy-duty vehicles, useless for anything else.

Good that they are glass fiber reinforced plastic and not rubber then.

Tires were hemp-reinfoced plastic, then steel-reinforced plastic, they are now actually fiberglass-reinforced plastic.

It doesn't matter. So long as elasticity is provided not by gas compression, but solid material compression/tension, that solid material will deteriorate fast.

Downvote me all you want, but this idea won't fly. It can't compete with regular tires at anything above 20mph.

Their FAQ (downloadable from https://michelinmedia.com/michelin-uptis/) does address this:

> 21. What will happen if some small stones or mud or snow get in between the structure of Uptis?

> The objective during the development of the commercial product is to test Uptis in all of these situations. Some preliminary tests show that stones, mud or ice/snow will not stay inside the Uptis structure.

Obviously preliminary tests aren't anywhere near enough to prove it's a nonissue, though.

It wouldn't be too crazy of an engineering trick to make the pores flex in a manner that causes them to crap out anything that's clogging them as the tire goes around.

I'm hoping that's a prototype that just shows the structure inside and not the final design. But I guess we'll find out, or they will in that trial.

Alloy wheels have had open designs for decades and that hasn't been a problem for them.

Those have bigger and fewer holes, and they don't look like an ant's nest.

Alloy wheels don't need to flex, though. If a rock wedges into nooks and crannies of this, perhaps it could mess up the performance. And perhaps it could cause damage since you'd have a harder material (rock) rubbing against a softer one (rubbery airless tire stuff).

Tires are different than wheels....

Looks like a complete pass through from one side to the other so washing them should remove most of that. Rocks might even fall out as the tyre rotates.

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