I just recently bought a touring bike with cantilever brakes and I am amazed at their simplicity. I recently read on Sheldon Brown's site that cantilevers used to be a hot commodity and could not be afforded by every-day cyclist. However, today cantilever brakes show up everywhere, especially on mass-produced mountain bikes. Worth noting; they are not showing up on racing bikes. This brings me to my question. It seems like cantilever brakes have a much simpler mechanism to employ the brake. And simple in this case equals weight savings. Why are racing bikes not using a lighter option for their brakes? It seems to me that the cantilever brake, using just the thin brake cable directly connected to the brake pad, would be lighter and more simple than the U-brake setup involving the two arms of the u-brake plus the brake pads, etc.
Granted, today's racing bikes have carbon fiber everything, and the braking system can use this rigid, light material for this application. However, I think that eliminating this apparatus completely, and linking the brake lever directly to the brake pad, as the cantilever system does, is the lightest option there is.
If there is something I am missing regarding this issue, please let me know. I am open to all discussion topics. That's what forums are for!