Model "S" Wheels/Tires

[tdelta1000]

Me again and this time I questions about the wheels & tire. I've seen several posts about the Mod "S" specs but not too many on the wheels/tires.

Does anyone know will there be a pressure gauge integrated in the core system of the "S"? or will the car have run flat tires?

If not run flat tires, were will the spare tire reside?

[efusco]

I'm quite confident that none of those decisions have been finalized.

Run flats would be nice, but considering that the car is more of a commuter vehicle than a highway vehicle I'd prefer to save the cost of the run flats and either just carry a doughnut spare (maybe under the hood) or even a little emergency flat kit...though that would preclude the tire pressure monitoring which I think is an almost guaranteed thing.

[vfx]

The current S prototype has run flat tires on it.

[tdelta1000]

It makes sense that they will use run flats but has Tesla made a concrete statement about the use of run flat tires? Also, who will be manufacturing those tires?

[vfx]

It makes sense that they will use run flats but has Tesla made a concrete statement about the use of run flat tires? Also, who will be manufacturing those tire?

I'd guess you are at least a year early with questions like that.

[tdelta1000]

VFX,

Here's a link on the subject of run flat tires.

Run flat tire information according to Wikipedia and its sources. (http://en.wikipedia.org/wiki/Run-flat_tire)

Here's what I found on the net:

Bridgestone RFT (Run Flat Tire)
Dunlop DSST (Dunlop Self-Supporting Technology)
Firestone RFT (Run Flat Tire)
Goodyear EMT (Extended Mobility Technology)
Kumho XRP
Michelin ZP (Zero Pressure)
Pirelli RFT (Run Flat Technology)
Yokohama Run Flat

[tdelta1000]

I found a run flat kit made for the Continental Tire company.

Conti Comfort Kit (http://www.conti-online.com/generator/www/us/en/continental/automobile/general/news/downloads/cck_infosheet.pdf)

[2blue4u]

In a few years, we'll all have to use run-flats. But don't wish for them for they do make for a harsher ride.

[ChrisC]

...though that would preclude the tire pressure monitoring which I think is an almost guaranteed thing.

It's now a safety mandate. From Tire-pressure monitoring system in Wikipedia (http://en.wikipedia.org/wiki/Tire-pressure_monitoring_system) :


The Firestone recall in the United States in the late 1990s which was attributed to more than 100 deaths from rollovers following a tire tread-separation, pushed the Clinton administration to publish the TREAD Act. This act mandates the use of a suitable TPM technology in order to alert drivers of a severe under-inflation condition of their tires. This act affects all light motor vehicles (<10,000 lb) sold after 1 September 2007.

Now, there are ways to satisfy this requirement without direct pressure readings, instead reading secondary effects, so the question of actual pressure measurement remains ...

As I recall it (and please correct me if wrong), Tesla was able to get waivers for the Roadster on some federal requirements by virtue of low volume, but for the Model S they should need to meet everything.

[tdelta1000]

Any idea on the weight of the wheels for the Model S? I ask this because weight can be an enemy of an EV vehicle.

[tdelta1000]

Someone mentioned that the tires that the running preproduction of the Model S is rolling on Advan Sport tires. After some research here's what I found.

255/30ZR21
Load Index 93 = 1433lbs (650kg) per tire
Speed Rating “Y” = 186mph (300kph) 93Y RF Treadwear: 180
Traction: AA
Temperature: A180 AA A 1433 lbs.
50 psi
10/32"
28 lbs. 8.5-9.5"
9"
10.2"
9.2"
27.2"
765
Country of Origin "JP" = JAPANJP

255/35ZR21
Load Index 98 = 1653lbs (750kg) per tire
Speed Rating “(Y)” = 186+mph (300kph) (98Y) RF Treadwear: 180
Traction: AA
Temperature: A180 AA A 1653 lbs.
50 psi
10/32"
29 lbs. 8.5-10"
9"
10.2"
9.2"
28.2"
737
Country of Origin "JP" = JAPANJP

295/25ZR21
Load Index 96 = 1565lbs (710kg) per tire
Speed Rating “Y” = 186mph (300kph) 96Y RF Treadwear: 180
Traction: AA
Temperature: A180 AA A 1565 lbs.
50 psi
10/32"
30 lbs. 10-11"
10"
11.6"
10.9"
26.9"
772
Country of Origin "JP" = JAPANJP

295/35R21
Load Index 107 = 2149lbs (975kg) per tire
Speed Rating “Y” = 186mph (300kph) 107Y XL N0 (Porsche) Treadwear: 280
Traction: AA
Temperature: A280 AA A 2149 lbs.
50 psi
11/32"
33 lbs. 10-11.5"
10.5"
11.7"
10.6"
29"
717
Country of Origin "JP" = JAPANJP

Preproduction Tesla Model S tire information (http://www.tirerack.com/tires/Spec.jsp?make=Yokohama&model=ADVAN+Sport&tirePageLocQty=)

[vfx]

Why not a low rolling resistance tire?

Corporate Site - Britek Tire and Rubber (http://energyreturnwheel.com/Home.aspx)

[Cobos]

Probably because they don't look as good on a prototype that isn't going to go more than maybe 20 miles. I suppose wheel options is something that they will expand on as needed when they approach lockin date. After all they don't need to redo much engineering to give another tire option.

Cobos

[tdelta1000]

I think I may have found the answer to my own question. While surfing on the Roadster side of the house I found this image:
http://emeraldsequoia.com/55screens/content/bin/images/large/IMG_1617_1.jpg

The screen shot is from the VDS in the Roadster. It gives me a clue as to tire pressure monitoing system that may be installed in the Model S. I think the Model S will have TPS system but the interface will look a lot nicer.

[DGreifinger]

Run flat tires are aweful! They have a terrible ride and are very expensive as well as non-repairable. I hope Tesla does not use them, or at least offers the option of traditional tires.

[Mark Petersen]

Witch type of run flat are you referring to, as there is several different types
as not all are created equal