Actual manufacturer's revs per mile specs are best but the calculator on
this page is much more useful than the one at miata.net -

http://brickwerks.hostinguk.com/VehicleSpecific/T3/info/mods/alloys/altwhls.htm

On Tue, Mar 16, 2010 at 12:39 PM, Mike S <mikes@flatsurface.com> wrote:

> At 02:26 PM 3/16/2010, John Bange wrote...
>
>> > I am wanting to know what the revs per mile of the Michelin
>> Agilles >205/65R15 C is
>>
>> I use this calculator:
>>
>> http://www.miata.net/garage/tirecalc.html
>>
>
> That calculator is way off with regard to rev/mile. It might be useful
> in comparing two different sizes, but not actual tires, since the only
> measurement of a real tire which can be expected to be exact is rim
> diameter. A tire with a section width of 210 may be called a 215,
> because 210 isn't a standard size.
>
> The problem with that calculator, and others I've seen, is that it
> figures diameter mathematically, assuming perfect circles, etc. A real
> world tire has a rolling radius which is smaller than that of a tire
> represented as a perfect circle (it compresses when loaded), which
> means it will turn faster.
>
> So where that calculator says a 215/60R16 does 771 revs/mile, Falken
> says their ZE-912 of the same size does 808. That's about a 5%
> difference.
>

--
Jake

1984 Vanagon GL
1986 Westy Weekender "Dixie"

Crescent Beach, BC

www.thebassspa.com
www.crescentbeachguitar.com
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