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Old 11-06-2010, 12:19 PM   #14 (permalink)
CapriRacer
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Quote:
Originally Posted by ShadeTreeMech View Post
What causes increased RR at higher speeds? Is it due to more heat buildup from tire deflection at such high rpms?

And I noticed you excluded other tires such as truck tires. The main difference coming to mind is the thicker sidewalls and tread of a truck tire vs a passenger vehicle.
My best guess is that it has to do with standing waves:



I think that passenger car tires with their increased deflection are more suspectible to this. Truck tires - in order to stand up to the miliions of miles that they are expected to last - are designed with lower amounts of deflection.

Quote:
Originally Posted by Boreas View Post
Since I am an amateur at mathematics.....Is the term g ,in the rolling resistance equation.........
Actually, it's a physics thing.

g - in this context - is the translation from mass to weight. Those of us who are used to the English system have trouble when we talk about mass, because we usually talk about weight - pounds.

But those who speak metric, normally speak in terms mass - grams. To get force - Newtons - you have to multiply grams by 0.00981. For reference, accelleration due to gravity is 32.2 ft per second squared or 9.81 meters per second squared.

Quote:
Originally Posted by RobertSmalls View Post
......Can you give me an alternative to CRR model?..........
Sorry, but no. I don't think there is much published that has enough data points to get a better feel for what is going on.
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