Understanding tire dimensions

[Salavar]

I have been on several websites including this one trying to get my head around sizing due to a mod I am considering.

I have a 29" Genesis and am considering a 26" wheel set (26 x 2.125), and am wanting to install 3 inch tires on them. What I can't determine from what I have read is what their diameter might be once inflated?

My frame has a ton of clearance both front and back, but I just don't know how wide they will end up after installation.

Any input or guidance would be appreciated.

Thanks

 

[udallcustombikes]

The tire's inflated dimentions will vary depending on the rim used. A 1.75" will result in the 3" tire being taller and narrower than if it was mounted on a 3" rim.

 

[Salavar]

The tire's inflated dimensions will vary depending on the rim used. A 1.75" will result in the 3" tire being taller and narrower than if it was mounted on a 3" rim.

That makes a lot of sense, thanks.