Marbles is the term used for the fragments of rubber that are shed from the tyre as it is exposed to extreme forces while the car is being driven in anger – practice, qualifying or the race. These are typically flicked off the racing line and tend to accumulate creating an area described as ‘dirty’.

The fragments can be treacherous to the cars as they act like marbles and greatly reduce grip.

Andrew Burden

The author Kiwi F1 Fan