Tire Pressure and Rolling Resistance

Tire Pressure and Rolling Resistance

Tire pressure significantly affects rolling resistance, comfort, and speed - recent research has challenged old "max pressure" assumptions.

Rolling Resistance Basics

• Energy lost to tire deformation as it rolls
• Higher pressure ≠ always faster
• Optimal pressure balances deformation and vibration losses
• Rough roads favor lower pressures

Optimal Pressure Guidelines

• 70kg rider, 25mm tires: 75-80 PSI front, 80-85 PSI rear
• 80kg rider, 25mm tires: 80-85 PSI front, 85-90 PSI rear
• 90kg rider, 28mm tires: 75-80 PSI front, 80-85 PSI rear
• Rough roads: Reduce 5-10 PSI
• Smooth roads: Increase 5-10 PSI

Tire Width Considerations

• Wider tires (28mm vs 23mm) can be faster at equal comfort
• Better suspension effect reduces vibration losses
• Slightly higher rolling resistance offset by comfort gains
• UCI allows up to 28mm in most races

Testing Your Optimal Pressure

Field test: ride the same loop at different pressures, measure average power required for the same speed. Lower pressure that maintains speed saves energy. Too low causes sluggish feel and pinch flat risk. Most riders run too high based on old "max pressure" myth.

Race Day Pressure Strategy

• Smooth TT course: Higher pressure (90-95 PSI)
• Rough cobbled classics: Much lower (50-60 PSI, wider tires)
• Mountain stages: Moderate (70-80 PSI for descending grip)
• Wet conditions: Lower pressure for better traction