Automotive Tires Without Air

pcman writes "It appears that in 10 years or so Michelin will have an airless tire. They are presenting them at the Paris Auto Show this week. They hope to adapt them for motorcycles, cars and heavier vehicles. They are non-pneumatic and made of elastic. You can read the whole story here. I am very interested and look forward to the day when I don't have to check tire air pressure. It is the 21st century after all."

Comments

Why stop at motor vehicles?

[El]

What we really need these for is bicycles... and I'll bet there is a bigger market in India and China for bicycle tires than for automobile tires.

Re:Why stop at motor vehicles?

[hitzroth]

There are a few problems with what you're saying.

First, rolling resistance has to do with how much energy is scrubbed away by the tire making contact with the ground (flexing and sticking and whatnot). What you're talking about with wheel weight is "rotational inertia," which is only relevant during acceleration (it takes no more energy to maintain a steady rotation of a heavy wheel than it does a lighter wheel if they have the same aerodynamics -- feel free to do the math yourself). Plus, while superlight wheels may feel really good at first, and while heavier wheels may start out feeling pretty sluggish, you'll get used to both after a ride or two.

Second, aerodynamics sucks dramatically more from the performance of a bicycle than any other factor. Don't believe me? Just remember how pleasant it is riding into a headwind.

Re:Prior art

[idiotfromia]

Uh, I believe oxen driven wagons were able to cross the untamed frontiers of the United States with airless tires. Before that, horses pulled wooden carts with solid wood wheels.

The point is that the new tires will be similar in design to the current and have the same stability and flexibility.

Probably will be outlawed in the US

[spikestabber]

Police spike strips will become useless. Anything innovating the DOJ wont like gets outlawed.

Re:Wouldn't want adjustability or anything...

[fmaxwell]

Huh? I've never towed anything with my car

Wuss. ;-)

and as for "heavier loads" I guess that means 4 people in the car instead of just me.

Or a vacation where the car has luggage in it. Or where you are carring a heavy item in the trunk.

I inflate my tires to the recommended pressure for my car and everything seems fine.

Most cars have two different recommended sets of pressures based on the load in the car. If you're taking the family to the beach in a fully loaded minivan, the proper, and safe, tire pressure is not the same as if mom and one kid are riding around town.

As for compensating for different vehicle weights, That could be solved by adjusting the solid tire for weight.

So now you have a 185/70R15 in six different vehicle weight classes, and each person has no way to adjust the pressure when he should.

How many people want to trade tires between vehicles (or even have two vehicles with the same tire size)?

That wasn't the point. The point was that you and I could each have vehicles that required 205/70R14 tires and your vehicle may weigh substantially more or less than mine. we could both buy the same tires and adjust tire pressure accordingly.

I've never done this, though I live in a climate where snow is common in the winter. I've never heard anyone even recommend doing this, so I don't think it's very commonplace.

See this link for information on it. It is very worthwhile in soft snow, sand, or mud. When I volunteer to drive for the hospital in snow emergencies, I always drop the tire pressure on my Jeep down to about 10-15psi. It's why Humvees have a CTIS, or Central Tire Inflation System. That way, they can adjust pressure for the terrain, lowering it for snow, mud, sand, etc.

The points you bring up are for the car enthusiast. The vast majority of people aren't car enthusiasts and want nothing to do with adjusting tire pressure for different conditions.

No, they are points for everyone. The vast majority of people aren't computer enthusiasts and want nothing to do with performing security updates or installing anti-virus software. Being in the majority doesn't mean that someone is right.