I was looking at some race car specs. The wheels were listed as 17x9, but the tires were listed as 24/61-17. What system of measurement is this? For the sake of comparison, how do I convert that to the usual 2xx/yyR17?

Thanks.

>>I was looking at some race car specs. The wheels were listed as 17x9, but the tires were listed as 24/61-17. What system of measurement is this? For the sake of comparison, how do I convert that to the usual 2xx/yyR17?
>>
>>Thanks.
>>

Most non DOT race tires use sizing much like flotation truck tires

24 = overall diameter
61 = width in inches
17 = wheel diameter

The part I am confused about is 61 - There is no way that its 61 inches wide.

Can I get clarification on this number?

Alex