Legally your tyres should have at least 1.5mm tread across ¾ of the tread pattern around the entire tyre. Worn tyres – things to look for include:

• Uneven wear on one side of your tyre
• Feathering or scalloping – this can be found by lightly running your fingers over the tyre and feeling the uneven ridges
• Abnormal bulges or bubbles in the side wall