Comment by ordersofmag
4 hours ago
Not to be pendantic (but to be pendantic) 80psi is the correct pressure for 28mm tires ridden briskly on good roads. At least according to ye olde Silca tire pressure calculator. Back in the day when folks ran 23mm tires they would typically run above 100psi (though that may not have been optimal...).
That calculator is wrong. Cycling people have been overinflating their tires for ages (as well as using too-narrow tires), with the assumption that the ground is perfectly smooth. Lower pressures yield higher efficiency (and better comfort) on rougher surfaces.