I can appreciate that an inner tube has a very hard job to do (especially at higher inflation pressures and potentially higher local momentary pressures when hitting bumps etc.), and that being compliant to mechanical stresses but hold the air trapped are kind of opposing requirements. I'm just a bit surprised that with all of the other funky materials we've got on bikes we're still dealing with rubber.
Of course, the same is true in money-no-object racing like F1 and MotoGP, so I don't know why I'm so surprised.
