Originally Posted by
ThermionicScott
Same rims, bigger tires on the "29'er" -- it's just marketing.
29'er rims are designed to accommodate wider tires without having to worry about the tyre rolling off.
As a trade off, you might not be able to use narrower tyres.
http://www.schwalbetires.com/tech_in...dimensions#rim
note that rim width is measured from the inside.
If you measure from the outside, subtract 5.5mm, which gives an approximate result.