The Intense Micro KNobby 26 inch...

...weights 690g although they used kevlar and "single ply Ultra Light Weight casing"

Ouch, thats a tribute to 2500 more knobbies then the much lighter 20" brother. What the fuck does Ultra Light weight casing mean? That the tire would be 1 kg without it?

I think you won't find the tire on many light weight bikes, sucks a little bit.