A valve drive of an internal combustion engine may include a camshaft, at least one cam follower, and a hydraulic actuating element. The camshaft may include at least one first cam structured as a brake cam and a second cam structured as an exhaust cam. The at least one first cam may have a reduced cam lift relative to the second cam. The at least one cam follower may be connected to an exhaust valve of the internal combustion engine via a rocker. The hydraulic actuating element may include a plunger that is adjustable to an extended position and a retracted position. When the plunger is in the extended position, the hydraulic actuating element may be operatively connected to the brake cam providing a braking stroke. When the plunger is in the retracted position, the hydraulic actuating element may be operatively disconnected from the brake cam providing a cylinder cutout.

A method of controlling an internal combustion engine in a vehicle that includes a cylinder, a fuel system for supplying fuel to the cylinder, an air guide arranged to guide an air flow to the cylinder, and an exhaust guide arranged to guide a gas flow from the cylinder, the method including controlling the engine to provide a braking torque, the control including terminating the supply of fuel to the cylinder, restricting the flow through the exhaust guide, and restricting the flow through the air guide. The control of the engine to provide a braking torque also includes determining a value of a rotational speed of a turbocharger of the engine, and adjusting, in dependence on the determined turbocharger rotational speed value, the restriction of the flow through the air guide, and/or the restriction of the flow through the exhaust guide.

An exhaust valve rocker arm assembly selectively opening first and second exhaust valves. The assembly includes an exhaust rocker arm and a valve bridge operably associated with the rocker arm and including a main body and a lever rotatably coupled to the main body. The main body is configured to engage the first exhaust valve, and the lever is configured to engage the second exhaust valve.

An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode, the exhaust valve rocker arm assembly selectively opening first and second exhaust valves and including a rocker shaft, exhaust valve rocker arm assembly and a ball engine brake mechanism. The exhaust valve rocker arm assembly has an exhaust rocker arm that receives the rocker shaft and is configured to rotate around the rocker shaft. The ball engine brake mechanism is configured on the exhaust rocker arm and selectively actuates a valve plunger causing an exhaust valve to perform engine braking. The ball engine brake mechanism includes a capsule assembly having a capsule, a biasing member and a ball. The capsule has a cylindrical body that extends between a first end having an actuation face and a second end having a spring return face.

A vehicle includes a variable displacement engine and a controller. The variable displacement engine has a plurality of cylinders and is configured to operate at a commanded air-fuel ratio. The controller is programmed to, in response to a command to perform a diagnostic test, operate the engine such that each of the cylinders is shut down for a portion of the diagnostic test while one or more of the remainder of the cylinders remain operating. The controller is further programmed to, in response to a deviation from the commanded air-fuel ratio exceeding a threshold while a first of the cylinders is shut down during the diagnostic test and a subsequent command to decrease the number of operating cylinders, shut down one or more of the plurality of cylinders other than the first of the cylinders.

A vehicle includes a variable displacement engine, a conduit, a sensor, and a controller. The variable displacement engine has a plurality of cylinders. The conduit is configured to channel exhaust gas away from the cylinders. The sensor is disposed within the conduit and is configured to measure an amount of particulate matter within the exhaust gas. The controller is programmed to, in response to a command to run a diagnostic test, operate each of the plurality of cylinders independently to produce an exhaust gas stream for each cylinder and measure the amount of particulate matter within each of the exhaust gas streams.

An exhaust valve rocker arm for an exhaust valve rocker arm assembly operable in a combustion engine drive mode and an engine braking mode, and configured to selectively open first and second exhaust valves, includes a body defining an aperture to receive a rocker shaft such that the body is rotatable about the rocker shaft, a bore defined in the body, and a rotating stepped engine brake capsule disposed in the bore and having a castellation mechanism. The rotating stepped engine brake capsule is movable between a locked, engine brake active position and an unlocked, engine brake inactive position.

A variable valve operating device for an internal combustion engine includes a cam carrier supported on a camshaft and shifting switching pins that are advanced into and retracted out of shift lead grooves defined in the cam carrier. The shift lead grooves include shift groove side walls having shift groove side wall surfaces from shift starting inflection regions of the cam carrier to shift ending inflection regions thereof. The shift groove side walls include particular shift groove side walls extending from axial positions of the shift starting inflection regions toward shift intermediate regions and also extending from circumferential positions of the shift intermediate regions disposed between the shift starting inflection regions and the shift ending inflection regions toward the shift starting inflection regions. The side walls have slanted outer circumferential surfaces extending from the circumferential positions progressively deeper toward groove bottom surfaces and reaching the shift starting inflection regions.

An internal combustion engine is provided with a variable valve operating apparatus, for use on a saddle-type vehicle. When a switching drive shaft is longitudinally moved under hydraulic pressure switched by a solenoid valve, a cam mechanism advances and retracts a switching pin. When the switching pin is advanced to engage in a lead groove in a cam carrier, the cam carrier is axially moved while rotating, to switch cam lobes to act on an engine valve. A solenoid valve is disposed on a left or right end in the leftward and rightward directions across the vehicle width, of a front or rear surface of a cylinder head. The solenoid valve is placed in an appropriate location in the cylinder head out of interference with other parts of the engine, thereby making the vehicle small in size.

A valve drive for an internal combustion engine may include a cam shaft including at least two cams rotationally attached thereto. The valve drive may also include a cam follower including a roller bolt including a rotatable roller arranged thereon. Additionally, the valve drive may include a lever device drivingly connected to the cam follower configured to adjust the cam follower between a first position and a second position. The valve drive may further include a rotatably supported control lever drivingly connected to the cam follower configured to adjust at least one valve of an internal combustion engine. The valve drive may include an actuator drivingly connected to the lever device configured to adjust the cam follower between the first position and the second position, the actuator may be connected to the cam follower in an articulated manner via the lever device.