DaveLeeNC

I have started paying attention to tire sizing, air pressures, and stuff like WRT damping road vibrations. It is pretty clear that the max width of an inflated 25mm (for example) tire will vary between manufacturers/models, rim width, and probably variations within a specific tire model on a given rim.

So let's say that I have a 23mm XYZ tire that when mounted/inflated on my bike measures 25mm max width. Then I have a 25mm ABC tire that when mounted/inflated on my bike also measures 25mm max width. Is it reasonable to assume that the 25mm ABC tire probably has a larger volume than the 23mm (25mm actual) tire because typically a wider tire is also a taller tire? I assume this is the case but didn't really know.

Thanks.

dave

Iride01 

Well if you are taking the trouble to measure the width, why don't you just measure the height too?

If by volume, you are talking volume of air space inside... I wouldn't try to suppose anything about the inside from outside measurements.

DaveLeeNC

I am currently riding 23's that measure 25. It is as wide as I can go, on the front anyway. I was wondering if finding 25s that measure 25 might actually be bigger.

Dave

Iride01 

Bigger how? If overall height of the tire or circumference is the "bigger" you are asking, then I'd say that is a definite maybe. But in the grand scheme of percentage of change, not much.

GuitarBob

My guess is that there would not be a predictable relationship -- that is, the result would vary by brand/model because in reality, even though they are spec'd as 23s or 25s, they all measure differently.