Originally Posted by bitingduck

The rim is probably your big limiting factor-- even the ellipse rims, which are among the beefiest track rims I've seen, are only rated to 145 or 150 or something. There's not a big advantage to super high pressures for clinchers, and some disdvantage- at high pressures you're going to increase your chance of blowing the bead off the rim going through a turn fast (seen it happen). You get a brief bead lift, the tube peeks out, explodes, then the bead sets back in place while you slide on the apron.