What license do you need to ride a 125cc bike?

To ride a 125cc bike in the UK, you need either a provisional motorcycle license combined with a Compulsory Basic Training (CBT) certificate or an A1 motorcycle license. The CBT allows you to ride a 125cc motorcycle on public roads, while the A1 license requires passing both a theory and practical test. In many other countries, similar requirements exist, often involving a specific motorcycle license category for smaller engine sizes. Always check local regulations for precise licensing requirements.