Bridgestone Announces Large Diameter Narrow Tires

[NeilBlanchard]

Here's an interesting article on these kinds of tires:

Interstitial Ad - Modern Tire Dealer

[gone-ot]

BIG bicycle tires!

[NeilBlanchard]

The VW XL1, the BMW i3,, and the Edison2 VLC use tall (large diameter) narrow tires. That seems to point to the efficiency advantage. Oliver Kuttner mentioned this kind of tire in the video I posted on the Edison2 thread.

[arcosine]

Id like a set on my Saturn.

[NachtRitter]

Originally Posted by NeilBlanchard

Here's an interesting article on these kinds of tires:

Interstitial Ad - Modern Tire Dealer

Interesting statement from that article:

By optimizing the structure of tires and using the most appropriate materials, Bridgestone achieved a rolling resistance coefficient 30% lower than conventional tire sizes such as 175/65R15.

[freebeard]

When I saw you had bumped the thread, I hoped there would be pricing, but I'll settle for 'in production'.

Bridgestone Corp.’s Ecopia ologic tire, size 155/55R19, has a larger vertical diameter and increased air pressure to limit changes in the contact patch. Introduced as the Large and Narrow concept tire, it is now in production, the company reports.

What happened? The prototype has a diameter ~3.5x the width while the 'production tire is ~6.5x. and it looks like a 'cheater slick'. Among the claimed benefits are lower road noise and better anti-hydroplaning. With that [lack of] circumferential grooves?

==>Red Model A Ford wire wheels on a '61 VW panel van.

[arcosine]

Originally Posted by freebeard

When I saw you had bumped the thread, I hoped there would be pricing, but I'll settle for 'in production'.

What happened? The prototype has a diameter ~3.5x the width while the 'production tire is ~6.5x. and it looks like a 'cheater slick'. Among the claimed benefits are lower road noise and better anti-hydroplaning. With that [lack of] circumferential grooves?

==>Red Model A Ford wire wheels on a '61 VW panel van.

Skinny tires don't hydroplane because there is no plane to hydro on. It goes by the square of the width, a tire twice as wide displaces twice the amount of water twice the distance, so the force pushing the tire off the pavement is 4 times.

[sheepdog 44]

Yes, as a user of relatively skinny tires i very much miss running through puddles at speed and getting a nice splash.

I'm glad something is coming of this. Tires are a big deal to getting good mpg and maximizing the useful power from a very small engine.

[niky]

Originally Posted by arcosine

there is no plane to hydro on

So help me, that got a chuckle. Have to remember that the next time I write an article on tires...

Skinny tires absolutely rock in the pouring rain. Did a slalom test in a few factory pick-ups, and the variant on the skinniest tires did pretty well, despite being shod in long-wearing ungrippy van meats... while higher end variants wearing wider "HT" tires took more effort to navigate the wet course. And we didn't even have enough water to form standing puddles. the higher pressure on the contact patches was enough to make the difference.

[freebeard]

Skinny tires don't hydroplane because there is no plane to hydro on. It goes by the square of the width, a tire twice as wide displaces twice the amount of water twice the distance, so the force pushing the tire off the pavement is 4 times.

Where does the extra water come from? My memory of research in the 70s [citiation needed] is that the only thing that made any difference was high air pressure and large circumferential grooves to carry the water past the tread.

And we didn't even have enough water to form standing puddles. the higher pressure on the contact patches was enough to make the difference.

Damp pavement then. VW Beetles drive the speedometer from the left front wheel. When you hit standing water and the speedo needle drops toward zero, you know your hydroplaning. For years I ran 145-15 on the front and 165-15 on the back. But you really find out, downhill in the mountains, there's more brakes than tires. Now it's 165-50-15 in front.

I've got a little brass caliper I've been holding up to the screen, and I've concluded the early picture is a 7" width on 19", and the Ecopia branded tire is about 4 1/4", so pretty close to 155mm.

Load and speed ratings?