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Old 12-20-2009, 04:37 PM   #55 (permalink)
winkosmosis
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Quote:
Originally Posted by thatguitarguy View Post
You should read more carefully, and don't try to manipulate my words to your own meaning. All I was saying is that higher tire pressure reduces the size of the contact patch. It's elemental physics.

It's hard to figure out what you are saying, because you are just asking questions. Are you being sarcastic? Ironic? Scientific?

Because a surface is rough does not mean that it that it has more traction.

Try this experiment: Get on your hands and knees on dry smooth pavement. Put as much pressure as you can on your right hand and slide it forward. Now look at the cuts and gouges and know that this didn't come because of traction, but because of lack of traction.

Now get on your hands and knees on an indoor maple basketball court, and try to slide your left hand forward. (The one not lubricated by hemoglobins.) You will find it much more difficult to move your hand forward. This is because of traction.

It's the reason you continually hear shoes squeaking on that basketball court during a game, but on an outdoor court or street, you do not hear the squeaks. This is because the glass smooth surface of the polished maple provides much more traction than the rough surface outside.

The caveat is the presence of moisture. The glass smooth surface with a tiny layer of moisture provides the perfect hydroplaning surface, while it takes more moisture outside. This is why the rough surface is better for driving puposes, because there will always be the chance of moisture outside, and the tiny layer of moisture will disperse to the bottom of the rough surface while the tiny peaks of the rough surface remain dry enough to provide some traction.

You said that friction stays the same regardless of contact patch size, which is incorrect. What I said about the rubber conforming to bumps in the road surface explains the reality that a bigger contact patch has more traction.


You're talking about race drivers wanting more bumps if it really helps. The surface is already rough. What race drivers want is WIDER TIRES.

Cars don't drive on basketball courts. They drive on pavement, which is a textured surface, both microscopically and macroscopically. If roads were made of basketball courts, you MIGHT be right about contact patch having no influence on traction.

Last edited by winkosmosis; 12-20-2009 at 04:46 PM..
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