Tyre Rolling Resistance Calculator — Compare Tyre Setups

Top racing tyres achieve Crr of 0.003-0.004 on smooth drums. Real-world Crr is typically 0.004-0.006 for good road tyres. Cheap tyres or knobby MTB tyres may be 0.008-0.012.

On real roads, often yes. Wider tyres at lower pressure deform less on rough surfaces (less energy lost to vibration). A 28mm tyre at 80 psi can be faster than a 23mm at 110 psi on typical UK roads.

For a typical 80-85 kg rider-and-bike system on smooth road at 30 km/h, rolling resistance costs roughly 25-40 watts (fast race tyres ~25-30 W, slower tyres ~35-40 W). At 40 km/h it rises to about 35-50 watts. Rolling resistance scales linearly with speed, so it is a larger share of your power at low speed and a smaller share once aerodynamic drag dominates above ~35 km/h.

Yes, typically by 2-5 watts per tyre compared to clincher with butyl tubes. The removal of tube-tyre friction and lower possible pressures both contribute.

A 10 psi reduction increases Crr by roughly 2-3% on smooth surfaces. However, on rough roads, lower pressure can actually be faster due to reduced vibration energy losses.