Suzuki Motor Corporation

Koichi Tanaka

Kunio Arase

Kei Hasegawa

Koji Mori

Kota Kezuka

There is provided a lubrication structure of an internal combustion engine. A transmission chamber is arranged adjacently at the rear of a crank chamber. An oil chamber communicates with a bottom part of the transmission chamber. A feed pump supplies oil in the oil chamber to a lubrication target part. A scavenging pump sucks the oil in the crank chamber and discharges the oil to the transmission chamber. The feed pump and the scavenging pump are arranged coaxially in a width direction of the internal combustion engine. At least a part of the scavenging pump is arranged higher than a lower end of the crank chamber. A rear end of the scavenging pump is arranged at the same position as a rear end of the crank chamber or in front of the rear end of the crank chamber in a front and rear direction.

Lubrication structure of internal combustion engine

Provided is a vehicle speed-change system including the following: a transmission positioned to the rear of a crank shaft of an engine; a transmission case that retains the transmission; a shift mechanism that has a shift cam which performs a speed-change operation of the transmission; and a shift actuator that operates the shift cam. The transmission includes a counter shaft positioned to the rear of the crank shaft, and a drive shaft to which rotation of the counter shaft is transmitted. The shift cam is positioned further to the rear than the counter shaft, and the shift actuator is arranged in a rear portion of the transmission case and to the rear of the shift cam.

Vehicle speed-change system

The present invention is capable of more smoothly changing a phase of a cam shaft in a rotation direction. A variable valve mechanism changes an opening/closing timing of an intake valve or an exhaust valve in response to an engine rotation speed. The variable valve mechanism includes: a cam sprocket which rotates in response to a rotation of a crank shaft; an intake cam shaft which is integrated with an intake cam and is provided to be rotatable relatively to the cam sprocket; and a link member that transmits a rotation from the cam sprocket to the intake cam shaft. The link member is supported by the cam sprocket to be swingable and swings in response to a change in rotation speed of the cam sprocket to rotate the intake cam shaft relatively to the cam sprocket.

Variable valve mechanism, engine, and automatic two-wheeled vehicle

An overhead valve actuation mechanism for an engine includes a camshaft that is rotatably supported by the cylinder head and includes one or a plurality of valve cams. The camshaft operates opening and closing of an intake valve and an exhaust valve via the valve cam. The only one camshaft is disposed within the one cylinder head. The camshaft has an axis center biased to a side of the exhaust valve with respect to a cylinder axis line as viewed from an axial direction of the camshaft.

Overhead valve actuation mechanism for engine

The present invention can achieve a variable valve mechanism having a simple and compact configuration. A variable valve mechanism changes an opening/closing timing of an intake valve or an exhaust valve in response to an engine rotation speed. The variable valve mechanism includes: a cam sprocket which rotates in response to a rotation of a crank shaft; an intake cam shaft which is integrated with an intake cam; an exhaust cam shaft which is integrated with an exhaust cam; and a governor flange that transmits a rotation of the cam sprocket to the intake cam shaft and the exhaust cam shaft. The intake cam shaft and the exhaust cam shaft are formed so that the other cam shaft is inserted through one cam shaft to be relatively rotatable. The governor flange is provided to rotate along with the intake cam shaft and rotates relative to the cam sprocket under a predetermined condition.

A motorcycle is provided with an engine unit having a crankcase and a cylinder assembly protruding diagonally frontward and upward from the crankcase. An air cleaner box has a rearward-descending shape extending from the upper side to the rear side of the cylinder assembly as seen in a side view to form a vertically elongating box shape. The air cleaner box is disposed between left and right frames of a chassis, and both side surfaces of the air cleaner box are separated from the chassis. The air cleaner box has a frontward-narrowing and rearward-narrowing width as seen in a top view. As a result, it is possible to obtain a sufficient box capacity and facilitate a compact design. In addition, it is possible to smoothly flow an air stream in the lateral sides of the air cleaner box.

Air cleaner structure of saddle-ride type vehicle

An overhead valve actuation mechanism for an engine includes a cylinder head, a camshaft that is rotatably supported by the cylinder head, includes one or a plurality of valve cams, and operates opening and closing of an air intake side or air exhaust side valve via the valve cam, a rocker arm that is swung by the valve cam of the camshaft and acts on the valve to open and close the valve, and a rocker arm shaft that is supported by the cylinder head and swingably supports the rocker arm. The rocker arm shaft includes a supporting portion supporting the rocker arm and a fixed shaft portion supported by the cylinder head. The supporting portion is formed such that a rotation axis of the rocker arm parallelly and slightly separates with respect to a center axis line of the fixed shaft portion.

A rocker arm includes a pivot portion that is journaled by a rocker arm shaft, a contact portion that projects from the pivot portion to a side of a valve cam, and a pressing portion that projects from the pivot portion to a side of a valve. While including a slipper projecting from the pivot portion in outer side in an axial direction to a side of a camshaft, an overhead valve actuation mechanism for the engine includes a stopper portion with which the slipper comes in contact when the rocker arm swings and reaches a predetermined position at a position opposing the slipper.

A plurality of cylinders are disposed in parallel in a vehicle width direction, a clutch chamber is disposed in either one of the right and the left in the vehicle width direction, an intake manifold, a fuel injection device, a throttle body, and an intake pipe are disposed between a cylinder assembly and an air cleaner in an upper part of a crankcase assembly. The throttle body is disposed on an opposite side in the vehicle width direction of the clutch chamber.

Engine unit of motorcycle

It is possible to simplify an internal structure of a silencer and it is possible to improve silencing performance while suppressing the increase of the size of the silencer. An exhaust pipe structure is constituted by an exhaust pipe () which is connected to an engine (), and a silencer () which is disposed under the engine. A silencer inlet () through which exhaust gas is introduced into the silencer is provided in the silencer and at the rear of a vehicle body. The exhaust pipe has a rear portion reversal pipe () by which a direction of an exhaust stream flowing rearward is reversed into a frontward direction. A downstream end side of the rear portion reversal pipe is connected to the silencer inlet. A silencer outlet () through which exhaust gas is discharged from the silencer is provided in the silencer. The silencer outlet is provided at the front of the vehicle body. Thus, exhaust gas can flow inside the silencer unidirectionally from the rear toward the front.

Exhaust pipe structure for vehicle

There is provided a link mechanism configured such that a shift rod driven by an operation of a gear shift pedal drives a shift shaft to rotate via a gear shift lever. A stroke sensor measuring a stroke amount, and a shift load sensor making a stroke motion in extension and contraction directions in accordance with shift-up and shift-down operating loads from the gear shift pedal are integrally provided to the shift rod.

Shift rod device of motorcycle

A motorcycle engine having cylinders arranged in parallel in a vehicle width direction, an air cleaner, a fuel tank arranged above the engine to cover the air cleaner, and a fuel injection device. The fuel injection device includes an electronic control throttle body unit electrically controlling a throttle body of the engine; an intake passage of down draft intake structure connecting the air cleaner and a combustion chamber of the engine in each of the cylinders; fuel injectors provided at the intake passage including a first fuel injector located on an intake downstream side and a second fuel injector located on an intake upstream side; and a drive motor of the electronic control throttle body unit arranged between the intake passage and the fuel tank and arranged on a same side as the first fuel injector and the second fuel injector and between the first and second fuel injectors.

Fuel injection device for engine of motorcycle

An intake control device includes: an air cleaner disposed above an engine; a pair of right and left intake ducts projecting toward a front of a vehicle body from the air cleaner to take an outside air in the air cleaner; and a sensor unit coupled to a throttle cable extended from a throttle grip, and detecting an operation amount of accelerator, in which the sensor unit is disposed between the pair of right and left intake ducts at a position above the engine and below the air cleaner.

Intake control device

A reflux structure for blow-by gas that returns blow-by gas generated in an engine to a clean side of an air cleaner to reflux the blow-by gas to the engine, the reflux structure for blow-by gas includes: a communication pipe that has a flow path introducing the blow-by gas from the engine to the clean side of the air cleaner; and an air funnel that is mounted on the clean side of the air cleaner and introduces intake air from a dirty side into the engine, wherein the communication pipe has a discharge port formed to discharge the blow-by gas to a side closer to a bottom than to an umbrella part of the air funnel around the air funnel.

Growing community of inventors

Hamamatsu, Japan

Koichi Tanaka