Maintaining the correct tyre pressure for your bike is important because it affects your grip, control, and speed when riding. It can also reduce the tyre's susceptibility to punctures and help it last longer. To test your tyre pressure, you need an accurate pressure gauge like the Topeak D2 SmartGauge. It can measure your tyre pressure very quickly without losing air and display it on a screen that you view easily. You can also bleed air out of your tyres using the SmartGauge and it will display the current pressure in real time so you can accurately attain the tyre pressure needed. The Topeak D2 SmartGauge can also be used with suspension forks and rear shock units.