Bicycle Mechanics - rim side wall width?

VeloCity states the outer rim width on all its rims but I need to know the inner rim width (before I buy) what is a reasonable estimate for this difference?
nice picture here (http://sheldonbrown.com/gloss_ba-n.html#beadseat)

VeloCity states the outer rim width on all its rims but I need to know the inner rim width (before I buy) what is a reasonable estimate for this difference?
nice picture here (http://sheldonbrown.com/gloss_ba-n.html#beadseat)

Not sure why that even matters. What rim are you looking at.

the dyad (http://www.velocityusa.com/default.asp?contentID=584)...
you can figure out what tires you can put inside the rim based on the inner rim width... i would like to know what tires i can fit in there.

the dyad (http://www.velocityusa.com/default.asp?contentID=584)...
you can figure out what tires you can put inside the rim based on the inner rim width... i would like to know what tires i can fit in there.

You've been given false information. The only width that's important is the outside width. The Dyad needs a min 25mm tyre and up.

Sheldon says otherwise (http://sheldonbrown.com/tire-sizing.html#isoetrto)

The ISO system uses two numbers; the first is the width of the tire or rim in millimeters (The actual tire width will vary a bit depending on the width of the rim. The rim width is the inner width measured between the flanges as shown in the diagram.)

Mavic gives the outer rim dimention as 19.6 mm. I have one here and the inner width is a little less than 15mm. Mavic says that the rim is good for tires from 19 to 28 mm.
My Open sport rim is 20.2 mm and Mavic recommends a tire width between 19 and 32 mm.
They don't give the inner width for any of their rims.
There seem to be some misunderstanding of the ISO standard.

Sheldon says otherwise (http://sheldonbrown.com/tire-sizing.html#isoetrto)

Let me explain it to you plainly.

Regardless of whether or not a tyre runs true to its marked size, once inflated to riding pressure the width of the tyre cannot be narrower than the *outside width* of the rim. Which is why it's the only width that matter for practical purposes. Go think about it. Not everything on Sheldons pages is correct, or useful if interpreted incorrectly.

If you must know the details, the guys at Veloicty USA are very quick to anwer questions. You can call them at (616) 243-3400 or email them at velocity@velocityusa.com I have spoken to them a few times and due to my location, even visited thier warehouse in Grand Rapids.