<VV>Tires

[Bruce Schug]

On Jan 9, 2006, at 6:55 PM, Frank DuVal wrote:

> Yes, the last two digits are decimals of the whole inches. But I have 
> seen cases, like Padgett, where the smaller number tire was wider than 
> the larger number tire. Probably caused by which part of the tire was 
> measured for the inch designation. Most of the inch by inch tires 
> (6.00 x 13, 7.60 x 14, etc.) are 84 ratio tires. Atlas Plycron comes 
> to mind. I could use two more 9.00 x 14 tires if anyone has them! No, 
> not for Corvair. :-D
>

I agree with what you said except for the aspect ratios.

I think the intent was for the 9.00-14 tire (for instance) to have a 
cross section of 9.00", but, like todays tires, they weren't always 
what they said they were. Obviously, they would only be their intended 
size on a "design" width wheel.

Interestingly, the manufacturer's dimensions I have for Corvair tires 
show that the designation and the actual section width varied for 
several different tires as follows:

6.50-13 tires had section widths of:

6.72
6.92
6.49
6.63
7.24
6.78
6.96
6.99

7.00-13 tires had section widths of:

6.99
7.26
7.27
7.20

7.00-14 tires had section widths of:

6.87
7.05
7.08

Note that all of these were  measured on a 5.0" wheel.

It is interesting to note that one 6.50 was wider than some 7.00's!

The manufacturers did not list aspect ration, although they could be 
computed.

The Tire and Rim Association published standards for these tires. 
Remember, this does not mean that any tires were actually these 
dimensions. These standards list the following:

6.50-13	Section width 6.7	Aspect ratio 87

7.00-13	Section width 7.1	Aspect ratio 86

7.00-14	Section width 7.1	Aspect ratio 90

Bruce

Bruce W. Schug
CORSA South Carolina
Greenville, SC
bwschug at charter.net

CORSA member since 1981

'67 Monza. "67AC140"