British Cycling maintains specific gear restrictions for youth riders across various age categories which have changed for the 2025 season. These regulations are detailed in the British Cycling Handbook, which is updated annually. The 2025 edition of the Handbook is now available here, with the updated regulations coming into effect on March 1, 2025.
For advice and guidance for choosing a suitable restricted gear ratio please ask a coach at a Welwyn Wheelers training session.