This has probably been posted many times before, and I've certainly heard it mentioned before, but I figured I'd post it anyway, since I had the opportunity.



On the left is a stack of 205/50R15 Azenis on 15x7 wheels. On the right is a stack of 195/60R14 Azenis on 14x6 wheels. Quite a difference in height, isn't there?

The stack on the right is 31 inches tall.

(31 / 4) * 25.4 = 196.85 mm ... OK, that's consistent with a 195 section width.

The stack on the left is 34 inches tall.

(34 / 4) * 25.4 = 215.90 mm

So 205/50 Azenis really are effectively 215 section width tires.

 

they are also mounted on wheels 1" wider than the 195's

you should either measure them mounted on the same width wheels, or unmounted for a more accurate representation of their relative width...

the 205 azenis was made for a 6.5" wheel - mounted on such a wheel it would likely be exactly 205mm wide...

 

I had both Azenis in 205 and Khumo 712 in 205 side by side, unrimed. The azenis is larger.

 

thing is though, if you stack the tires like that, the sidewalls are what are touching between the tires. My stack of mounted 225/45/17 Azenis were 1/8" shorter than 245/40/17 Kumhos on the same wheel. BUT, the Azenis bows in a lot more from the sidewall to usable tread portion. The Azenis puts down much less rubber, compared to what one might think if judging solely by the height of the stack. The sidewall-to-sidewall width is useful for answering suspension clearance questions though.

 

What I had heard mentioned before was specifically that the 205 Azenis was more like a 215. It does not apply to Azenis in general. I am kind of curious if this applies to the 205/15 RT-615 as well.

If I recall correctly, the section width that is quoted in a tire size refers to the sidewall width, not the tread width, so measuring a stack like that should be reasonable. Take the stack of 195s for example.

I know what Safir's saying about the wheel width (which is why I mentioned it). However, I don't see the 205s giving up 10mm of section width from a 0.5 inch change in wheel width. Maybe, but I'd be surprised.

 

I noticed the same thing when I got my 205.55.R16 azenis, I thought I was going bonkers.

 

The 205 in the RT-615 is slightly more narrow than the old RT-215. Just slightly.

The 615 is quite a bit lighter though. The sidewall is not as stiff, however.