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Old 05-01-2010, 07:23 PM   #103 (permalink)
rmay635703
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Quote:
Originally Posted by CapriRacer View Post
Aren't there a number of different questions on the table?

1) Does the size of a tire's footprint affect grip?
Rather pointless to argue over whats known, the footprint affects grip when the surface is not solid like blacktop or cement, AKA sand, snow etc. It can increase grip if it "cuts" through snow/water to a hard surface. It can decrease grip if it doesn't "grab" enough free material like snow or mud.

Quote:
Originally Posted by CapriRacer View Post
2) Does inflation pressure affect a tire's grip?

These may appear to be the same question, but asked in a different way, but I think you'll find they have some interestingly different aspects that bear exploration.
It can affect the geometry of how the tire distorts, again whether this is good or bad depends on application.

Quote:
Originally Posted by CapriRacer View Post
Lastly,

3) Friction theory: Do tires behave according to classical fiction theory, where F = µN, nad where µ has a lower value for sliding friction than for static friction.

So which question are we trying to answer?
It isn't so much the tire as the surface you are driving on as alluded to in #1

My take is that if you know the behavior of your tires at a certain pressure (mine are at 60psi) and drive responsibly (and have the experience to do so) This conversation is likely irrelevant.

In the 1,000,000+ miles I've driven I have never had a blowout (or an accident above 5mph), I have had a tire punctured twice (both in gravel lots by glass or nails) and I have had the valve stem regulator removed as a prank by some arse wipe. Except for those on the suburban most tires have exceeded their rated lifespan and usually fail because they become unbalanced or undulated in the sidewall or the tread quite late in the game mind you.

As for handling terrain on road, I have never "lost control" on any public road at speeds above 5mph. I believe knowing your vehicle is much more important than the tires you are using or the pressure they are at, and obviously you can adjust your tire pressure if conditions are bad, not like it takes all day to do.

Only had trouble stopping once and that was because my rear brakes became inop on wet leaves which resulted in a 2mph collision and no damage.

The main issues with excessive pressure is excessive wear to your suspension, there are definately places you DO NOT WANT too much pressure and you do have to avoid certain obstacles you may otherwise ignore. The 2ft deep potholes around here are murder.
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