Brakes Wheels 2nd Gen Tires Most liked posts in thread: Larger Contact Patch for Tire Selection (17in)

That is exactly what I tell my Dr. when I go in for a check up and get on the scale. Wider is better.


Lololl:ihih::lol::lol::lol:

 

Contact patch area remains the same no matter the size of the tire. What changes is the shape of the contact patch.

A narrow width will have a contact patch such as...

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While a wide tire will have a contact patch that encompasses the same area but shaped more like...

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That represents a lot of deflection... Wonder why racing bicycle tires are so narrow? Less rolling resistance due to a small contact patch?

 

:cornut::lol::cornut: Now I remember why I quit arguing with Nathan.:lol::lol:

Jason

 

Unscientific opinion:

For our purposes, you want the short and wide contact patch as that would work better with the lateral forces the tire experiences in the "twisties".

 

darn beer swilling fiat drivers

 

I am confused. What do you mean "let you pass"? ut:

 

When I am up for tires again I am going from my 215 / 45 / 17's to 245 /40 /17's...wider is better.

 

In the above example, since the weight didn't change, the #/in. squared stayed the same, the contact patch area didn't change.

Soooooo, continuing on this same thought....
If no other changes are made except removing a whole bunch of weight, like seats, interior trim etc.... getting down to race weight..... The contact patch would be reduced, because the weight was reduced. And as long as you don't break tire adhesion..... do both vehicles have the same cornering speed on a track?

 

Sorry Nathan but if both tires have the same diameter and air pressure, I don't see how your contact patches would be correct? The wider the tire the larger the contact patch would be by width, neither widening nor narrowing would effect the patch front to rear..... Please correct me if I am wrong.

 

From Tire Rack....

"The shape of a tire's contact patch greatly influences its performance and is dependent on the profile, or "aspect ratio" of the tire. Low profile tires (most performance tires) have a short and wide contact patch that is more effective in converting driver inputs into very responsive handling, cornering stability and traction, especially on dry roads.

"High profile tires (trucks, most passenger tires) have a long and narrow contact patch that provides more predictable handling, smoother ride and gives better wet weather and snow traction."

 

...and they are referencing diameter. A wider and larger diameter tire would have more contact patch too. The width of two tires with the same diameter would effect the size of the contact patch.

 

Given 2 tires with the same diameter such as in a Plus One application the tire with the greater width will have a contact patch that is shorter and wider then the OEM spec narrower section width tire.

A visual example



Granted, the example pictured above and my other ASCii version are much greater than actual but are that way to prove the point.

 

True, but if you reduce the weight you can also lower the tire pressure to retain the same contact patch. :ihih:

 

:cornut::devil::ihih: ...........and avoiding the beer bottles flying out of the Fiat Abarth 500 which is in front of you, going too slow, and won't let you pass!:lol::lol::lol::lol::lol:

Jason

 

A really interesting (but long) read, with actual tests and measurements on the relationship of tire size, load, pressures, etc.

All in a static environment - things change with cornering dynamics - but still very interesting... and completely destroyed some of my long-held beliefs about this topic.

Fact or Fiction? Tire contact patch and air pressure.

 

Exactly, suffice it to say that there are many variables that effect the size of a tires contact patch. One cannot throw one simple blanket ratio over it... Many things to consider, yes there is. 2cents

 

Take the skinny contact patch racing and I'm a believer that one will opt for the fatter contact patch instead... Just my .02. :beer

 

You and me both, my brother.