Abstract: A lubricating oil composition containing a base oil, an organic molybdenum compound, and a metallic detergent, wherein the metallic detergent contains calcium sulfonate, and the content of the calcium sulfonate in terms of calcium atoms is 0.12% by mass or more based on the mass of the composition, the content ratio of molybdenum atoms derived from the organic molybdenum compound to soap groups derived from the metallic detergent based on the lubricating oil composition, [Mo/soap groups], is 0.02 or more at a mass ratio, and the HTHS viscosity at 150° C. is 1.3 mPa·s or more and less than 2.3 mPa·s. The lubricating oil composition has low viscosity and excellent lubricity.

Abstract: A lubricating oil composition containing a base oil (A), a molybdenum-based friction modifier (B), a metal-based detergent (C), and a dispersant (D), in which the dispersant (D) contains a non-boron-modified polyisobutenyl succinic bisimide (D1). The IR spectrum of the non-boron-modified polyisobutenyl succinic bisimide (D1) is determined by an FT-IR method, having a ratio [Abs (1705 cm?1)/Abs (1390 cm?1)] of a peak intensity Abs (1705 cm?1) at 1705 cm?1 to a peak intensity Abs (1390 cm?1) at 1390 cm?1 is 7.5 or less. A content of the non-boron-modified polyisobutenyl succinic bisimide (D1) is 50 mass % or more based on a total amount of the dispersant (D), and contains a kinematic viscosity at 100° C. is 9.3 mm2/s or less. The lubricating oil composition has an excellent effect of reducing a friction coefficient while containing a molybdenum-based friction modifier and a succinimide compound.

Abstract: A lubricating oil composition may contain a base oil (A) and a dispersant-type viscosity index improver (B), in which the nitrogen atom content based on the solid content of the dispersant-type viscosity index improver (B) is 0.50 to 1.50% by mass, and the weight-average molecular weight (Mw) thereof is 100,000 or more, and the content in terms of the solid content based on the total amount of the composition of the dispersant-type viscosity index improver (B) is more than 0.05% by mass and less than 5.0% by mass. The lubricating oil composition may exert excellent wear resistance in a state contaminated with soot.

Abstract: A lubricating oil composition, containing a base oil (A), a metal-based detergent (B), and a molybdenum compound (D), the lubricating oil composition having a content of molybdenum atoms derived from the molybdenum compound (D) of 0.05% by mass or more, a base number of 4.0 mg KOH/g or more, and an HTHS viscosity at 150° C. of 1.3 mPa·s or more and less than 2.3 mPa·s.

Abstract: A lubricating oil composition containing a base oil, an organic molybdenum compound, and a metallic detergent, wherein the metallic detergent contains calcium sulfonate, and the content of the calcium sulfonate in terms of calcium atoms is 0.12% by mass or more based on the mass of the composition, the content ratio of molybdenum atoms derived from the organic molybdenum compound to soap groups derived from the metallic detergent based on the lubricating oil composition, [Mo/soap groups], is 0.02 or more at a mass ratio, and the HTHS viscosity at 150° C. is 1.3 mPa·s or more and less than 2.3 mPa·s. The lubricating oil composition has low viscosity and excellent lubricity.

Abstract: Provided are a method for determining the disposition position of a spherical joint for coupling exhaust pipes to each other in an exhaust system, and an exhaust system, which enable engine vibrations to be more effectively damped. In the present invention, strain gauges are attached at a plurality of locations in an exhaust system (1), simulated vibrations which simulate engine vibrations are imparted to the upstream-side end of the exhaust system (1), and bending strain is measured at each strain gauge. On the basis of the bending strain measured at each strain gauge, detected is a position at which generated is a bending moment that is equal to or greater than or equal to a torque amount which generates a maximum static friction force between a spherical inner-circumferential surface (26) and a spherical outer-circumferential surface (27) of a spherical joint (2) which come into contact with each other, and the detected position is determined to be the disposition position for the spherical joint (2).

Abstract: Provided are a method for determining the disposition position of a spherical joint for coupling exhaust pipes to each other in an exhaust system, and an exhaust system, which enable engine vibrations to be more effectively damped. Inthepresent invention, strain gauges are attached at a plurality of locations in an exhaust system (1), simulated vibrations which simulate engine vibrations are imparted to the upstream-side end of the exhaust system (1), and bending strain is measured at each strain gauge. On the basis of the bending strain measured at each strain gauge, detected is a position at which generated is a bending moment that is equal to or greater than or equal to a torque amount which generates a maximum static friction force between a spherical inner-circumferential surface (26) and a spherical outer-circumferential surface (27) of a spherical joint (2) which come into contact with each other, and the detected position is determined to be the disposition position for the spherical joint (2).