An internal combustion engine including a crank chamber housing a crankshaft connected to moving parts able to supply torque to the crankshaft, a lubrication circuit, an oil sump for collecting the lubricating oil, the engine including a separating partition which separates the crank chamber from the oil sump, in which the lubrication circuit includes a first oil pump and a second oil pump, where the first oil pump is fluidically connected in aspiration to the crank chamber and in delivery to the oil sump, the second oil pump being fluidly connected in aspiration to the oil sump and in delivery to the crank chamber by means of the lubrication circuit, to re-introduce pressurised oil in the crank chamber and lubricate the moving parts.