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Old 10-03-2016, 10:03 AM   #10 (permalink)
rmay635703
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Quote:
Originally Posted by CapriRacer View Post
So why hasn't the US government required labels for RR (fuel economy)? Because the tire size plays a large role in what the value is and the regulators (NHTSA) want to use RRF (Rolling Resistance Force) which makes smaller tires look better (which also means overloaded tires), where the tire industry wants to use RRC (Coefficient of Rolling Resistance), which makes larger tires look better. The courts have ruled that NHTSA's proposal is unacceptable, but NHTSA has not yet issued a revise regulation.
So what you are saying is that nobody wants to rate the tire so you can tell what affect on fe it will have?

I would think you would load the tire to 75% of its rating and measure the drag it creates and test the amount of wind drag at a simulated 65mph fender less drive.

Then weight the two measures appropriately to create a drag metric.

One could then subjectively compare a real metric as opposed to one that is likely meaningless.
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