Pray tell, what does the speed rating have to do with tire wear????
Tread life is indicated by the treadwear number the manufacturer places
on the sidewall, not not by the speed rating. The speed rating means the
tire will not disintegrate if sustained at speeds within its rating, and
is generally viewed by us as an indicator of "toughness" or
"responsiveness" i.e. Z-rated might be crisper than V-rated, definitely
sharper than H-rated. Speed rating is a demonstration by the
manufacturer of the tire's ability to perform accroding to certain
standards.
Wear rating is an _arbitrary_ number, pretty much undefinable, assigned
by the manufacturer as a guideline for tread life in standard highway
conditions. A higher number means longer life, but Goodyear's numbers
may or may not compare to Firestone's. (If you come from camcorders,
it's like the LUX rating they used to rave about; Sony's LUX numbers
were good for comparing to other Sony's, but useless for comparing to
Canons or Hitachis.) The theory is that there is a standard 100 life
against which tires are measured, and I'd even heard that you should
multiply the wear number by 200 to get a mileage figure. Doesn't
happen, though.
Walter Fooshee
Dixie Region Probe GT
John Whitling wrote:
>
> . . .
>
> Collectively you (we) have a choice ... pay more money for more tires
> and deal with all the associated hassles OR push for for a simple easy
> "Z" speed rating requirement for all race tires. You'll all, in your
> infinite wisdom, tell me that for some magic reason tires cannot be
> regulated. They are too complex for that ... black magic, if you will.
> Well BS ... find the problem with a simple speed rating. Speed ratings
> would not be cheated by tire companies. Nothing could be easier to
> enforce.
>
> . . .
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