Bicycle Tire Pressure And Rolling Resistance

42 5 kg 94 lbs rr 120 psi 8 3 bar rolling resistance at 100 psi 6 9 bars single tire speed.

Bicycle tire pressure and rolling resistance. Tire pressure isn t a set it and forget it thing. Wheel energy ran two rolling resistance tests with each tire at 112 psi and 84 psi. Additionally safety is significantly reduced with high tire pressures. This is typically measured on a smooth metal drum or roller and tells us how much energy it takes for the tire to deform and return to shape on the roller as it spins which generates heat.

Rolling resistance does vary slightly with tire pressure but it s not linear and it depends on the surface. Traditional wisdom says that higher tire pressure equals lower rolling resistance because on a smooth surface hard tires flex less and create a. In recent tests the rolling resistance between a tire inflated to 85 psi as opposed to a tire inflated to 110psi is negligible. The results presented here assume that the tires are kept at 100 psi 6 9 bars.

Rolling resistance at 120 psi 8 3 bars single tire speed. 42 5 kg 94 lbs rr 80 psi 5 5 bar rolling resistance at 60 psi 4 1 bars. 42 5 kg 94 lbs rr 100 psi 6 9 bar rolling resistance at 80 psi 5 5 bars single tire speed. 29 kmh 18 mph load.

On smooth surfaces like the one used in the tests shown above moderately high tire pressure say 100 110 psi for a 25 mm tire actually rolls slower than either a lower pressure 80 psi or a higher pressure 130 psi. If you try to take a sharp turn at speed around a moderately slippery corner with overinflated tires it s not going to be pretty. Once the power stabilizes software records the power it takes to drive the wheel at that speed on the roller. 29 kmh 18 mph load.