A 2013 R56 MINI One had a 1.6 litre Peugeot THP 'Valvetronic' petrol engine and that is chain cam. The tensioner can start rattling and need replacing but the timing chain does not normally need to be changed. If it's a diesel then that is belt cam and timing belt, tensioner, waterpump and aux belt all need replacing every five years or 60,000 miles whichever comes first: www.honestjohn.co.uk/carbycar/mini/one-r56-2007/