After many years of using high pressures (120psi on TT bike with 23mm tyres, 110psi road bike with 25mm tyres) and i weigh 74kg with about extra 10kg with bike and equipment etc. I’ve been using this calculator recently after heard about it on Triathalon show podcast…reduced my pressure significantly (About 85-90psi on TT now and 80-85psi road) and feels better AND faster!!