Abstract: A method of supplying air to an air spring biasing one of an intake valve and an exhaust valve of an internal combustion engine to a closed position is disclosed. The method includes: driving an air compressor with a motor prior to starting of the internal combustion engine, the air compressor fluidly communicating with the air spring to supply air to the air spring; determining that a predetermined condition has been reached; starting the engine once the predetermined condition has been reached; and driving the air compressor with a rotating shaft of the engine once the engine has started.

Abstract: A method of supplying air to an air spring biasing one of an intake valve and an exhaust valve of an internal combustion engine to a closed position is disclosed. The method includes: driving an air compressor with a motor prior to starting of the internal combustion engine, the air compressor fluidly communicating with the air spring to supply air to the air spring; determining that a predetermined condition has been reached; starting the engine once the predetermined condition has been reached; and driving the air compressor with a rotating shaft of the engine once the engine has started.

Abstract: An internal combustion engine has at least one intake valve and at least one exhaust valve. A first spring biases the at least one intake valve to a closed position. A second spring biases the at least one exhaust valve to a closed position. At least one of the first and second springs is an air spring. An air compressor fluidly communicates with the air spring to supply air to the air spring. The air compressor is operatively connected to a rotating shaft of the engine to be selectively driven thereby. A motor is operatively connected to the air compressor to selectively drive the air compressor. A method of supplying air to the air spring of the above engine is also disclosed. A method of supplying air to an air spring of an engine having both a mechanical and an electrical air compressor is also disclosed.

Abstract: A poppet valve has a valve head and a valve stem. A piston is capable of reciprocating motion relative to a housing along a reciprocation axis. The piston has a valve-receiving portion for receiving therein an end portion of the valve stem. A cotter secures the valve stem to the piston. A cap is disposed around the valve-receiving portion. A cap lateral portion extends away from the cap end portion in the direction of the valve head. The valve-receiving portion is held between the cap end portion and the cap lateral portion in a direction parallel to the reciprocation axis. At least part of the cap lateral portion is angled toward the reciprocation axis. The part of the cap lateral portion is closer to the reciprocation axis than at least part of the valve-receiving portion. A method of assembling a valve assembly is also described.

Abstract: An internal combustion engine has at least one intake valve and at least one exhaust valve. A first spring biases the at least one intake valve to a closed position. A second spring biases the at least one exhaust valve to a closed position. At least one of the first and second springs is an air spring. An air compressor is disposed inside the cylinder head and fluidly communicates with the air spring to supply air to the air spring. The air compressor being disposed between a crankshaft and a cylinder head cover in a direction parallel to a cylinder axis is also disclosed.

Abstract: An internal combustion engine has a crankcase, a crankshaft, a cylinder block, at least one piston, a cylinder head assembly, and a cooling system for cooling at least a portion of the engine. The cooling system has a first cooling jacket for cooling a first side of the cylinder block, a second cooling jacket for cooling a second side of the cylinder block, and a cylinder head cooling jacket for cooling the cylinder head assembly. A coolant inlet and a coolant outlet fluidly communicate with the first and second cooling jackets respectively. Coolant flowing in the cooling system flows from the coolant inlet to the first cooling jacket, then to the cylinder head cooling jacket, then to the second cooling jacket, and finally to the coolant outlet. A cylinder block, an engine cooling system, and a method of cooling an engine are also disclosed.

Abstract: A poppet valve has a valve head and a valve stem. A piston is capable of reciprocating motion relative to a housing along a reciprocation axis. The piston has a valve-receiving portion for receiving therein an end portion of the valve stem. A cotter secures the valve stem to the piston. A cap is disposed around the valve-receiving portion. A cap lateral portion extends away from the cap end portion in the direction of the valve head. The valve-receiving portion is held between the cap end portion and the cap lateral portion in a direction parallel to the reciprocation axis. At least part of the cap lateral portion is angled toward the reciprocation axis. The part of the cap lateral portion is closer to the reciprocation axis than at least part of the valve-receiving portion. A method of assembling a valve assembly is also described.

Abstract: An internal combustion engine has at least one intake valve and at least one exhaust valve. A first spring biases the at least one intake valve to a closed position. A second spring biases the at least one exhaust valve to a closed position. At least one of the first and second springs is an air spring. An air compressor is disposed inside the cylinder head and fluidly communicates with the air spring to supply air to the air spring. The air compressor being disposed between a crankshaft and a cylinder head cover in a direction parallel to a cylinder axis is also disclosed.

Abstract: An internal combustion engine has at least one intake valve and at least one exhaust valve. A first spring biases the at least one intake valve to a closed position. A second spring biases the at least one exhaust valve to a closed position. At least one of the first and second springs is an air spring. An air compressor fluidly communicates with the air spring to supply air to the air spring. The air compressor is operatively connected to a rotating shaft of the engine to be selectively driven thereby. A motor is operatively connected to the air compressor to selectively drive the air compressor. A method of supplying air to the air spring of the above engine is also disclosed. A method of supplying air to an air spring of an engine having both a mechanical and an electrical air compressor is also disclosed.

Abstract: An internal combustion engine has a crankcase, a crankshaft, a cylinder block, at least one piston, a cylinder head assembly, and a cooling system for cooling at least a portion of the engine. The cooling system has a first cooling jacket for cooling a first side of the cylinder block, a second cooling jacket for cooling a second side of the cylinder block, and a cylinder head cooling jacket for cooling the cylinder head assembly. A coolant inlet and a coolant outlet fluidly communicate with the first and second cooling jackets respectively. Coolant flowing in the cooling system flows from the coolant inlet to the first cooling jacket, then to the cylinder head cooling jacket, then to the second cooling jacket, and finally to the coolant outlet. A cylinder block, an engine cooling system, and a method of cooling an engine are also disclosed.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.