Gasoline fuel formulation containing (i) tricyclene, which is suitably biologically derived, and (ii) a gasoline base fuel. The formulation may contain one or more additional biofuel components or oxygenates: it may for example include ethanol, or ethanol together with one or more additional biofuels. The invention also provides a method for preparing the formulation, its use in a spark ignition engine, and the use of tricyclene in a gasoline fuel formulation for various purposes, including to enhance lubricity.