A V8 engine, each bank of which is configured such that four crank pins connected to four piston pins via a connecting rod are positioned at 90° intervals when viewed from one end of a crankshaft. The four crank pins on the bank side are offset by 60° relative to the four crank pins on the bank side when viewed from the one end.

A internal combustion engine (10) comprising a cam crank assembly (75) having a planetary gear assembly (2900), an intake cam (90) and an exhaust cam (92), the planetary gear assembly (2900) having drive gear (2910) rotationally secureable to the crank shaft (22), a piston gear (2912) rotationally engaged with the drive gear (2910), and a piston assembly (70) rotationally attached to the piston gear (2912).

An air-cooled internal combustion engine including a crankshaft rotating about a crankshaft axis, a first cylinder having a first cylinder head, a second cylinder having a second cylinder head, and a blower assembly. The blower assembly includes a blower housing, a first fan, and a second fan. The first fan is positioned proximate the first cylinder and the second fan is positioned proximate the second cylinder. The first fan and the second fan are each received within the blower housing.

An air-cooled internal combustion engine including a crankshaft rotating about a crankshaft axis, a first cylinder having a first cylinder head, a second cylinder having a second cylinder head, and a blower assembly. The blower assembly includes a blower housing, a first fan, and a second fan. The first fan is positioned proximate the first cylinder and the second fan is positioned proximate the second cylinder. The first fan and the second fan are each received within the blower housing.

Internal combustion engine with cylinders disposed radially around an axis (Z), in each of which slides a piston carrying out reciprocating rectilinear movements, reversibly transformed into a continuous rotation of an output shaft by: an active unit and passive unit each respectively having a planet gear, the axis of which is parallel to (Z), being capable of meshing with a ring gear, being maintained on its orbit via a planet carrier and having a pitch diameter identical to the pitch radius of the corresponding ring gear. The planet gear is driven in rotation by the planet gear and/or the planet carrier. Each planet gear is respectively rigidly connected to a connecting rod having crank pins, the axes of which are parallel to the axis (Z), pass through the pitch circle of the corresponding planet gear and being capable of cooperating by contact with rods rigidly connected to the pistons.

The present invention provides an internal combustion engine comprising a crankshaft, the crankshaft comprising main bearing journals and cranks for connecting the crankshaft to piston rods of the engine, wherein the crankshaft is provided with counterweights, wherein at least a first counterweight is formed as a separate element and connected to the crankshaft. The present invention is characterized in that at least a second counterweight is formed integrally with the crankshaft.

The present invention provides an internal combustion engine comprising a crankshaft, the crankshaft comprising main bearing journals and cranks for connecting the crankshaft to piston rods of the engine, wherein the crankshaft is provided with counterweights, wherein at least a first counterweight is formed as a separate element and connected to the crankshaft. The present invention is characterized in that at least a second counterweight is formed integrally with the crankshaft.

Engine includes: crankcase housing crankshaft extending in vertical direction; cylinder block mounted on side of crankcase and formed with cylinder; cylinder head mounted on side of cylinder block and provided with air inlet port and air outlet port communicating with cylinder; cylinder head cover mounted on side of cylinder head and covering air inlet port and air outlet port; mount case including: supporting portion provided below crankcase and cylinder block and supporting crankcase and cylinder block; and extending portion extending from supporting portion below cylinder head and cylinder head cover; oil pan provided below mount case and storing lubricating oil; and communication tube communicating first space formed between cylinder head and cylinder head cover and second space formed between mount case and oil pan. Communication tube is provided between cylinder head cover and extending portion.

Engine includes: crankcase housing crankshaft extending in vertical direction; cylinder block mounted on side of crankcase and formed with cylinder; cylinder head mounted on side of cylinder block and provided with air inlet port and air outlet port communicating with cylinder; cylinder head cover mounted on side of cylinder head and covering air inlet port and air outlet port; mount case including: supporting portion provided below crankcase and cylinder block and supporting crankcase and cylinder block; and extending portion extending from supporting portion below cylinder head and cylinder head cover; oil pan provided below mount case and storing lubricating oil; and communication tube communicating first space formed between cylinder head and cylinder head cover and second space formed between mount case and oil pan. Communication tube is provided between cylinder head cover and extending portion.

Methods and systems are provided for controlling imbalance with an exhaust tuning valve. In one example, a method may include adjusting a first exhaust tuning valve in response to combustion torque imbalance in a first and second group of cylinders. Additionally or alternatively, the position of the second exhaust tuning valve may be adjusted in response to an imbalance generated by the same group of cylinders.