Dry-sump, four-stroke engine

The present invention relates to a dry-sump, four-stroke engine (10) having a lubrication device, the engine comprising a crankcase (11) having a crank chamber (16) and a separate adjoining chamber (20) separated by a divider wall (64), wherein a through hole (67a,67b,67c) is formed in the divider wall (64) connecting the crank chamber (16) with the separate chamber (20). It has the objective of providing a dry-sump, four-cycle engine having a lubrication device capable of reliably returning the lubricant oil to the crank chamber (16) with a simple structure. Therefore, the invention proposes that said through hole (67a,67b,67c) is openable and closable by a crank web (24a) of a crankshaft (22) housed in the crank chamber (16).