Old vs new tyres

[mcrews]

Kinda hard to argue with 10,XXX,XXX tires being sold With tread........

But hey, let's start saying how everybody needs to be driving on donut spares.....

[gone-ot]

Originally Posted by mcrews

Kinda hard to argue with 10,XXX,XXX tires being sold With tread........

But hey, let's start saying how everybody needs to be driving on donut spares.....

...or Police Cars driving on spare donuts?

[MetroMPG]

Originally Posted by redpoint5

Here is what I found from Tirerack:

Thanks for the additional info!

[redpoint5]

Originally Posted by ecomodded

Braking distance is severely affected by tread wear, a worn tire takes 50 to a 100% longer distance to come to a panic stop then a new tire.
I'll take the braking ability of a new tire over the RR of a worn tire anytime.

I'm having to remove my foot from my mouth after looking into your claim and finding evidence to support it.

The link shows a test in which a passenger car and truck took nearly twice as long to stop from 70mph with worn out tires when compared to new.

Originally Posted by mcrews

Kinda hard to argue with 10,XXX,XXX tires being sold With tread........

But hey, let's start saying how everybody needs to be driving on donut spares.....

That brings us to Mcrews post showing that tread is clearly thought to be important. Even if one lived in Death Valley, having tread just for the possibility of encountering infrequent rain more than justifies the marginal loss in performance and wear the other 99.9% of the time.

Tread is often unnecessary, but essential to safety some of the time.

[mcrews]

I have 269,000 miles on my 2002 Q45 Sport.
I replace the Kuhmos every 40-44k miles.
From personal experience alone, I can tell you that worn tires suck.
I'm just not going to trade .001 better mpg for the risk.
Pump up to 45 psi and use nitrogen. And run tires w/ tread.

ANd buy a scangauge.

[redpoint5]

Originally Posted by mcrews

I'm just not going to trade .001 better mpg for the risk.

More like 0.7mpg for your vehicle, but I get your point

[MetroMPG]

Nitrogen is an unnecessary expense if you check your tire pressure regularly.

---

It's worth emphasizing that the stopping distance comparison that Tire Rack did was in wet conditions only. They didn't test in the dry. They also artificially "aged" the shaved tires by baking them in an industrial oven for several weeks.

So the idea that dry traction may be unaffected (or even improved) by reduced tread depth still holds.

Tread is often unnecessary, but essential to safety some of the time.

No argument there. Just clarifying their test.

[roosterk0031]

Tire Test Results : What Honest Abe Doesn't Tell You About Minimum Tread Depths: Part 2 - Dry Braking

Part 2 is dry testing, but only the car, brand new vs 4/32 & 2/32, all stopped within 1.5 feet of each other 50 mph to 0. And worn tires corner better, which kind of tells me the cooking in the oven didn't affect the rubber much.

So during the summer, newer tires on front, wear out old on rear, front's do most of the braking, wet or dry and I'm not cornering that fast, at least when wet.

[ecomodded]

I remember seeing a chart of the stopping comparison many years ago and it stuck, I cannot find that particular article or chart but did come across the video companion to the link that " redpoint5" has posted, from the tire rack.

http://www.youtube.com/watch?v=zA6MUlVNkLM

I am actually surprised that a worn tire performs better on dry roads. I always assumed the rubber compound in road tires would not grip as the race slicks do.

[gone-ot]

...which is *why* drag slicks are, well, slick = no tread, just ALL surface contacting rubber.