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Michelin Airless

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Re: Michelin Airless

#181

Post by checker »

bkanber wrote: post #168
dsr_ wrote: post #128

Earlier quoted context omitted.

The Earth's atmosphere is about 80% nitrogen and a little less than 20% oxygen, with some carbon dioxide, argon, variable amounts of water vapor, and some pollution. What's "nitro oxygen", then?

My guess is parent comment misspoke and meant pure nitrogen -- which does indeed help with tire pressure. The ideal gas law still applies, so there will be seasonal changes in pressure, but there will be much less exfiltration (via 'permeation', specifically) of gas through the material (N2 has a larger 'kinetic diameter' than O2; O2 will permeate 3-4x faster through rubber than N2).

So if regular air is 80% nitrogen already, won't the tires move towards 100% nitrogen with each top off since the tires will be retaining the nitrogen more than the oxygen? Sounds like a marketing trick unless they're filling newly mounted tires with 100% nitrogen.

Re: Michelin Airless

#182

Post by throwaway0a5e »

legulere wrote: post #166
arghwhat wrote: post #82

Earlier quoted context omitted.

A lot of heavy equipment drives around with water-filled tires, so it's already there. Definitely not what you meant though.

Also trains drive around with solid metal tires.

Trains have the benefit of exceptionally smooth "roads"

Re: Michelin Airless

#183

Post by dboreham »

xxpor wrote: post #97
arghwhat wrote: post #82

Earlier quoted context omitted.

A lot of heavy equipment drives around with water-filled tires, so it's already there. Definitely not what you meant though.

Hmm, why water filled? I can't think of any advantages, but can think of downsides such as a massive increase in unsprung weight.

Nothing is sprung on a wheel loader or a scaper.

Re: Michelin Airless

#184

Post by throwaway0a5e »

erik_landerholm wrote: post #103
xxpor wrote: post #97

Earlier quoted context omitted.

Hmm, why water filled? I can't think of any advantages, but can think of downsides such as a massive increase in unsprung weight.

https://tractoraddict.com/tractor-tires-filled-with-water/ Beet juice is interesting! lol

Beet juice is soooooooo much better for the environment than the salts it is replacing. Unfortunately it is slightly more expensive so we get to continue poisoning our waterways with salts.

Re: Michelin Airless

#185

Post by dboreham »

xxpor wrote: post #97
arghwhat wrote: post #82

Earlier quoted context omitted.

A lot of heavy equipment drives around with water-filled tires, so it's already there. Definitely not what you meant though.

Hmm, why water filled? I can't think of any advantages, but can think of downsides such as a massive increase in unsprung weight.

Sometimes foam is used rather than water.

Re: Michelin Airless

#186

Post by throwaway0a5e »

dsr_ wrote: post #128
hollander wrote: post #116

Earlier quoted context omitted.

I use nitro oxygen in my tyres. Pressure problems are gone.

The Earth's atmosphere is about 80% nitrogen and a little less than 20% oxygen, with some carbon dioxide, argon, variable amounts of water vapor, and some pollution. What's "nitro oxygen", then?

That's the point. He's being sarcastic and calling "atmospheric air" "nitro oxygen"

Re: Michelin Airless

#187

Post by 8ytecoder »

LargoLasskhyfv wrote: post #173
8ytecoder wrote: post #157

Earlier quoted context omitted.

Don't get me wrong - I'd expect Michelin to have done some testing to see NVH is within tolerance levels right? Airless is really close to working for bikes. If I were commuting on a bike now I'd be comfortable going for it. The downsides - painfully hard installation, uphill resistance, ...etc. - will be worth it.

Really? There are small cans of spray which you can have easily with you. Got a flat? Look where, pull it out. Spray the foam in. Turn the wheel for a minute, look for overseen leaks, maybe, and pull stuff out of them. Turn wheel a few more times. Pump. Or use car-adapter for pump at gas station. Those stuff costs between 2 and 4€ for a can of sprayfoam, and maybe 50ct for a small adapter(sugar cube like, but cylindr…

You make it sound simple. It's not when I'm commuting. Even to use the sprayfoam sealers - I need to first identify the puncture and that's not always obvious. I've usually just changed the entire tube.

Re: Michelin Airless

#188

Post by YossarianFrPrez »

bkanber wrote: post #174
8ytecoder wrote: post #157

Earlier quoted context omitted.

Don't get me wrong - I'd expect Michelin to have done some testing to see NVH is within tolerance levels right? Airless is really close to working for bikes. If I were commuting on a bike now I'd be comfortable going for it. The downsides - painfully hard installation, uphill resistance, ...etc. - will be worth it.

I also want to add, since this is more of a deep auto-industry thing, that NVH testing is almost like longitudinal health studies. NVH engineers actually have charts of which specific frequencies our internal organs resonate at . For a layperson it's easy to imagine that NVH testing is just a matter of setting up a dB meter and some accelerometers to make sure things aren't bouncing around too much, but it's actually…

This was very cool to read; thanks for such an informative comment.

I imagine this will sound naive, but I wonder why this sort of vibration can't be addressed with shock absorbers in the seats?

Re: Michelin Airless

#189

Post by throwaway0a5e »

bkanber wrote: post #174
8ytecoder wrote: post #157

Earlier quoted context omitted.

Don't get me wrong - I'd expect Michelin to have done some testing to see NVH is within tolerance levels right? Airless is really close to working for bikes. If I were commuting on a bike now I'd be comfortable going for it. The downsides - painfully hard installation, uphill resistance, ...etc. - will be worth it.

I also want to add, since this is more of a deep auto-industry thing, that NVH testing is almost like longitudinal health studies. NVH engineers actually have charts of which specific frequencies our internal organs resonate at . For a layperson it's easy to imagine that NVH testing is just a matter of setting up a dB meter and some accelerometers to make sure things aren't bouncing around too much, but it's actually…

And this stuff is exactly why it's a million times less fatiguing to drive a vehicle from 2020 over one from 1990, even if you control for almost every other variable by picking one that has changed minimally (i.e. a few panel vans and many medium duty trucks)

Re: Michelin Airless

#190

Post by Scoundreller »

smilekzs wrote: post #76
725686 wrote: post #67

Earlier quoted context omitted.

Maybe the noise they generate is good for EVs which are dangerously quiet for pedestrians?

Valid point, although pedestrian safety is mostly discussed in the low-to-mid-speed regime ( = 65 MPH). There might be some overlap though. Also worth pointing out: NVH is not just Noise --- it includes Vibration and Harshness that are only felt by the people inside the vehicle.

And effective at rattling off any untorqued/loose nuts/bolts.
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