A continuous variable valve duration apparatus includes a cam unit, a cam formed on the cam unit, a camshaft inserted into the cam, a guide bracket, a guide shaft mounted on the guide bracket and disposed perpendicular to the camshaft, wherein a guide screw thread is formed on the guide shaft, a wheel housing disposed within the guide bracket, an inner wheel rotatably inserted into the wheel housing and movable perpendicular to the camshaft, a worm wheel disposed within the wheel housing, wherein an inner screw thread configured to engage with the guide screw thread is formed inside the worm wheel and an outer screw thread is formed on the worm wheel, a control shaft, a control worm formed on the control shaft, and a wheel elastic portion mounted to the wheel housing.

There is provided an assembling structure of an engine. An oil control valve unit is configured to control oil pressure in a variable valve timing device of the engine. The oil control valve unit is installed on a cylinder head. The cylinder head is assembled to a crankcase. An outer wall of the cylinder head is formed with an opening into which the oil control valve unit is partially inserted. A mating surface of the cylinder head and the crankcase is fastened by at least a pair of bolts spaced apart across the opening.

An internal combustion engine defining at least one cylinder, the internal combustion engine including a first camshaft lobe, a second camshaft lobe, a valve in fluid communication with the at least one cylinder, a pivot, and a follower in contact with and operatively engages the pivot, the valve, the first camshaft lobe, and the second camshaft lobe. During use, the follower is operable in a first mode, in which the follower is configured to transmit motion between the first camshaft lobe and the valve, and a second mode, in which the follower is configured to transmit motion between the first camshaft lobe and the valve and the second camshaft lobe and the valve.

An internal combustion engine includes a cylinder and a valve assembly configured to activate and deactivate the at least one cylinder. The valve assembly includes an intake valve configured to control air flow into the at least one cylinder. A controller outputs a first control signal to the valve assembly to deactivate the at least one cylinder in response to detecting a deceleration event. The controller also outputs a second control signal to command the valve assembly to delay opening the intake valve from a closed position after re-activating the cylinder so that the torque output produced in response to re-activating the cylinder is reduced.

An engine system includes a first camshaft, a second camshaft, a first camshaft phaser, and a second camshaft phaser. The first camshaft phaser has a first camshaft sprocket, and the second camshaft phaser has a second camshaft sprocket. The engine system also includes a crankshaft spaced from the first and second camshafts, and a crankshaft sprocket coupled to the crankshaft. The engine system further includes a timing chain coupled to the first and second camshaft sprockets, and the crankshaft sprocket. The timing chain is configured to transmit torque from the crankshaft sprocket to the first and second camshaft sprockets upon rotation of the crankshaft. The engine system further includes a biasing member extending from a first end portion coupled to the first camshaft phaser to a second end portion coupled to the second camshaft phaser to maintain tension on the timing chain between the first and second camshaft phasers.

A sensor assembly for a sliding camshaft of a motor vehicle is provided. The sliding camshaft includes a base shaft that extends along a longitudinal axis and rotates about the longitudinal axis. The sliding camshaft further includes lobe banks rotationally fixed to the base shaft. Each lobe bank is axially movable between first and second positions relative to the base shaft. The sensor assembly includes a detection element rotationally fixed relative to the base shaft and axially movable between first and second positions relative to the base shaft. The sensor assembly further includes a sensor operably coupled to the detection element and configured to generate a signal indicative of an axial position of the detection element relative to the base shaft and at least one of an angular speed of the base shaft and an angular position of the base shaft about the longitudinal axis.

A sensor assembly for a sliding camshaft of a motor vehicle is provided. The sliding camshaft includes a base shaft that extends along a longitudinal axis and rotates about the longitudinal axis. The sliding camshaft further includes lobe banks rotationally fixed to the base shaft. Each lobe bank is axially movable between first and second positions relative to the base shaft. The sensor assembly includes a detection element rotationally fixed relative to the base shaft and axially movable between first and second positions relative to the base shaft. The sensor assembly further includes a sensor operably coupled to the detection element and configured to generate a signal indicative of an axial position of the detection element relative to the base shaft and at least one of an angular speed of the base shaft and an angular position of the base shaft about the longitudinal axis.

A saddle riding vehicle includes: a body frame; a fuel tank; an upright internal combustion engine; a fuel injection device; and a high-pressure fuel pump. The high-pressure fuel pump is configured to be driven by one of an intake-side camshaft and an exhaust-side camshaft. The high-pressure fuel pump is mounted on an upper surface of a cylinder head cover in an attitude inclined rearward toward the other of the camshafts. The high-pressure fuel pump can thus be protected from disturbances from the sides, and the length of a high-pressure pipe for feeding fuel from the high-pressure fuel pump to the fuel injection device can be shortened. The vehicle protects the high-pressure fuel pump from disturbances from the sides, and prevents acceleration of vaporization of fuel by reducing heat which the high-pressure fuel pump receives from the cylinder block.

A cylinder head of an internal combustion engine includes a cylinder head main body which is formed with a main body side plug insertion hole into which an ignition plug is inserted, a cam holder which is fixed to the cylinder head main body and forms cam bearing portions together with the cylinder head main body, wherein the cam bearing portions rotatably support an intake camshaft and an exhaust camshaft, respectively, and wherein the cam holder is formed with a holder side plug insertion hole which communicates with the main body side plug insertion hole and into which the ignition plug is inserted, and a knock pin which is disposed across the main body side plug insertion hole and the holder side plug insertion hole to restrict assembly positions of the cam holder and the cylinder head main body.

A method of two-step variable valve lift (VVL) malfunction avoidance learning control may include: in a two-step VVL system which is operated with a main lift and a secondary lift, verifying, by an electronic control unit (ECU), an operation avoidance area based on locking of a lock pin of a cam follower ; performing VVL operation learning, in which a failure of occurrence of the second lift is determined on the basis of a locking failure of the cam follower due to an initially set value of the operation avoidance area; and reflecting the operation avoidance area to the two-step VVL system with a corrected set value which is obtained through the VVL operation learning.