Tire Pressure. Rider Weight. Tire Width.

Not sure how accurate this is, but found this guide to tire pressures versus rider weight and tire width:

Tire Width=20: Pressure(psi) = (0.33 * Rider Weight in lbs) + 63.33

Tire Width=23: Pressure(psi) = (0.33 * Rider Weight in lbs) + 53.33

Tire Width=25: Pressure(psi) = (0.33 * Rider Weight in lbs) + 43.33

Tire Width=28: Pressure(psi) = (0.33 * Rider Weight in lbs) + 33.33

Tire Width=32: Pressure(psi) = (0.17 * Rider Weight in lbs) + 41.67

Tire Width=37: Pressure(psi) = (0.17 * Rider Weight in lbs) + 26.67