An internal combustion engine that includes an oil baffle in the oil sump. The internal combustion engine may include a crankcase comprising an oil sump containing an oil reservoir, a crankshaft, and an oil baffle positioned within the oil sump. The crankshaft may be a vertical crankshaft and a first balance shaft may extend upward from the oil baffle. The crankshaft may be positioned within the oil baffle and a drivetrain may, also optionally, be positioned in the oil baffle. The internal combustion engine may be configured such that the oil reservoir has a first oil level when the internal combustion engine is off and a second oil level when the internal combustion engine is running at normal operating conditions. The first oil level is above a floor of the oil baffle. The second oil level may, also, be above the floor of the oil baffle.