In some embodiments, a fuel rail for a two-stroke internal combustion engine includes a fuel rail body, a fuel inlet component integrated within the fuel rail body as a one-piece component and in fluidic contact with a fuel line, one or more fuel exit ports in fluidic contact with a cylinder of a combustion engine, and one or more fasteners adapted to secure the fuel rail body to a cylinder wall of the cylinder of the combustion engine

An engine is provided with: an engine body; and a top cover that covers the engine body, wherein at least a pair of engaging claws are provided to lateral walls, on both sides, of the top cover so as to extend downward, and a pair of engaging holes with which the engaging claws engage are provided to the engine body side. Each of the engaging claws is provided with a plate section that is provided so as to extend downward, and a bulging section that is provided to the leading end of the plate section and that bulges inward from the plate section, and the bulging section engages with the bottom surface of an inner wall section of the corresponding engaging hole.

A chain cover is configured to cover a timing chain that transmits rotation of a crankshaft of an internal combustion engine to a camshaft. The chain cover includes a crankshaft-side opening forming portion that defines a crankshaft-side opening into which the crankshaft is inserted, and a general portion that is a section different from the crankshaft-side opening forming portion. The crankshaft-side opening forming portion is made of a first material. The general portion is made of a second material. The first material and the second material are different from each other.

In an internal combustion engine, a breather chamber can be formed without increasing the number of component parts. The internal combustion engine (1) comprises an engine block (30) defining a cylinder (2); a case member (19) fastened to a lower part of the engine block to define a crank chamber (4) jointly with the engine block; and a bearing member (50) fastened to the engine block in the crank chamber to rotatably support a crankshaft; wherein the engine block is provided with a central recess (134) formed in a part thereof to which the bearing member is fastened, a blow-by gas inlet passage (112, 116, 121) communicating the central recess with the crank chamber, and a blow-by gas return passage (122, 118) forming a part of a passage communicating the central recess with an intake device, the central recess and the bearing member jointly defining a central breather chamber.

Provided is an engine device that can enlarge a space inside a case without lowering support stiffness. An engine (2) is attached to a case (11) via support parts (81, 82). A rear lower portion support part (82), which is one of the support parts, includes an attachment rib (11b) as a mounting part provided in the case (11) and an attachment bracket (91) fastened to a bottom of a crankcase (46) by a fastening bolt (90) and attached to the attachment rib (11b). The fastening bolt (90) penetrates through a through hole (92a) provided in the attachment bracket (91) and is screwed into a screw hole (46e) formed obliquely inward at a corner of the bottom of the crankcase (46).

An internal combustion engine includes: a cylinder block including a bulkhead formed so as to separate adjacent cylinders; a crankshaft including a counterweight; and a gas-vent hole which is formed in the bulkhead within a radius of rotation of the counterweight when seen from below a piston bottom-dead-center position and an axial direction of the crankshaft, and which communicates between the adjacent cylinders. The counterweight includes at least one of a concave portion and a through-hole formed at at least a part of a region of the counterweight opposed to the gas-vent hole during rotation of the crankshaft. The concave portion hollows in a direction away from the gas-vent hole, the through-hole penetrating through the counterweight in a direction away from the gas-vent hole.

A crank cap assembly including a single crank cap rotatably supporting a crankshaft includes: a fastening member fastened to the crank cap, a mass member; and an elastic rubber member elastically attaching the mass member to the crank cap. The elastic rubber member includes a first rubber part arranged between the fastening member and the mass member and a second rubber part arranged between the crank cap and the mass member. The first rubber part and the second rubber part are arranged to be aligned in the mounting direction when attaching the crank cap to an engine body, and the elastic rubber member is formed so that a length in the mounting direction is longer than a maximum length in a cross-section of the elastic rubber member perpendicular to the mounting direction.

Systems and methods are provided for a cylinder block having one or more bulkheads. The bulkheads provide a dual-wall structure that may enhance the stiffness of the cylinder block in bending and torsion. The bulkheads may also provide an oil drain to allow oil to directly drain through a hollow core of the bulkhead. An overflow outlet may be formed in an inner wall of a bulkhead. In some implementations, a cylinder block with bulkheads may increase an oil capacity of an engine.

An internal combustion engine includes: a cylinder block including a bulkhead formed so as to separate adjacent cylinders; a crankshaft including a counterweight; and a gas-vent hole which is formed in the bulkhead within a radius of rotation of the counterweight when seen from below a piston bottom-dead-center position and an axial direction of the crankshaft, and which communicates between the adjacent cylinders. The counterweight includes at least one of a concave portion and a through-hole formed at at least a part of a region of the counterweight opposed to the gas-vent hole during rotation of the crankshaft. The concave portion hollows in a direction away from the gas-vent hole, the through-hole penetrating through the counterweight in a direction away from the gas-vent hole.

A support structure for supporting a conduit of an engine includes a bracket assembly having a platform, a pair of brackets, and a pair of fixtures. The platform supports the conduit. Each bracket includes a first lateral post coupled to the platform, a second lateral post coupled to an engine block, a first longitudinal post, and a second longitudinal post. Also, a lateral distance between the first longitudinal post and the second longitudinal post increases in a direction away from the first lateral post towards the second lateral post. Each bracket also includes a stiffener connecting the first longitudinal post and the second longitudinal post. Each fixture includes a pair of legs and couples the platform to an engine head. Further, each fixture includes a web structure having a central portion and a plurality of stems connecting to the pair of legs.