According to one aspect of this disclosure, a grooving tool is provided. The grooving tool has a body with a plurality of recesses. Plural inserts assembled into each of the recesses. The recesses include a cutting edge for forming grooves in an engine cylinder wall when rotated in one rotational direction. The insert also includes a peening surface extending in the opposite rotational direction from the cutting edge for deforming the upper edges of the grooves when rotated in an opposite rotational direction.

An engine servicing system includes a motorcycle that has an engine. The engine has a cylinder head, an intake valve and an exhaust valve. A mount is provided and the mount is selectively coupled to the cylinder head. A plurality of bolts is provided and each of the bolts extends through the mount and engages the cylinder head at predetermined points on the cylinder head to retain the mount on the cylinder head. A compression unit is provided and the compression unit is removably coupled to the mount. The compression unit engages each of the intake valve and the exhaust valve such that the compression unit selectively compresses each of the intake valve and the exhaust valve. In this way each of the intake valve and the exhaust valve may be serviced while the engine is mounted in the motorcycle and without removing the cylinder head from the engine.

A piston and process for manufacturing a piston includes an upper part providing an upper combustion surface including a top land, a land ring and a combustion bowl. An undercrown surface is formed under the combustion bowl. A lower part including pin bosses and a piston skirt are formed under the undercrown surface. At least one of the upper part and the lower part are formed with metal injection molding.

A method for producing a groove structure in an internal surface of a pin bore of a piston may include providing a rotatable boring bar with at least one cutting tool; advancing the boring bar while rotating at a first rotational speed in a direction of rotation with a first feed speed into the pin bore and introducing at least one helical first groove of the groove structure with a first depth and a first width into the internal surface; and retracting the boring bar, subsequent to introducing the at least one helical first groove, from the pin bore with a second feed speed while maintaining rotation at a second rotational speed in the direction of rotation; during the retracting of the boring bar at least one helical second groove is introduced into the internal surface.

A coated aluminum piston, for an internal combustion engine includes an area of the piston having a plasma oxide layer which is sealed with a coating that comprises a polysilazane-based, a water glass-based or polysiloxane-based polymer. A method of coating the piston is also provided.

A cylinder block assembly includes a cylinder block having cylinders and a plurality of crank caps fixed to the cylinder block. The crank caps are arranged such that one of the crank caps is disposed on each of both sides of each of the cylinders in the alignment direction and among the plurality of crank caps arranged in line, each of a center crank cap located at a center position and two side crank caps respectively located at both ends has a hole or a groove in such a manner as to be more easily deformable than intermediate crank caps each of which is located between the center crank cap and one of the side crank caps when a load is received from the crankshaft.

A piston for an internal combustion engine includes a piston body having a top surface and having formed therein a combustion bowl surface, a base material of the piston body having a first thermal conductivity, a first layer of metal bonded to the top surface of the piston body, the first layer of metal having a second thermal conductivity that is lower than the first thermal conductivity, and a second layer of metal bonded to the first layer, the second layer of metal having a third thermal conductivity that is higher than the second thermal conductivity.

A component for an engine is provided. The component includes a thermal barrier coating applied to a body portion formed of metal, such as steel or another ferrous or iron-based material. According to one embodiment, a bond layer of a metal is applied to the body portion, followed by a mixed layer of metal and ceramic with a gradient structure, and then optionally a top layer of metal. The thermal barrier coating can also include a ceramic layer between the mixed layer and top layer, or as the outermost layer. The ceramic includes at least one of ceria, ceria stabilized zirconia, yttria, yttria stabilized zirconia, calcia stabilized zirconia, magnesia stabilized zirconia, and zirconia stabilized by another oxide. The thermal barrier coating can be applied by thermal spray. The thermal barrier coating preferably has a thickness less than 200 microns and a surface roughness Ra of not greater than 3 microns.

An engine block for an internal combustion engine of a motor vehicle has a cylinder within which a piston can be movably accommodated between a top dead center and a bottom dead center and has a cylinder bore, the internal cylinder diameter of which expands in the direction of the bottom dead center. The internal cylinder diameter expands only below the region in which a piston system change takes place during operation of the internal combustion engine. The internal cylinder diameter tapers from the top dead center to the region.

A problem is to provide a sliding member capable of improving friction characteristics under an environment of a lubricant containing Mo, and a production method therefor. A solution is a sliding member 10, wherein a sliding portion 11 is formed of a metallic material, and the sliding member 10 has, at a surface layer part of the sliding portion 11, a Ti-containing thermally sprayed coating 12 formed by thermally spraying, as a thermal spraying material, a metallic material containing Ti as a composition. The sliding member 10 slides under the environment of the lubricant containing Mo as an additive, in which active Ti exposed on a surface by sliding accelerates decomposition reaction of the additive contained in the lubricant to form a molybdenum disulfide-containing low-friction coating having low friction on the surface of the sliding portion 11.