Abstract: To concentrate mass, to lower the center of gravity, to efficiently and optimally arrange an intake part for making a compact vehicle body. A cylinder inclined to the rear is arranged under a fuel tank and a body of an intake box is housed between a radiator arranged in front of the cylinder and the cylinder. An upper part of the body of the intake box is fixed to a body frame at the bottom of the fuel tank and air taken in is supplied to an intake port through an intake funnel and a throttle body respectively built-in. A lid of an intake duct can be extractably inserted into a window hole provided to the front of the body, a duct part integrated with the lid is arranged over the radiator, and an air intake guide port takes a flow of air in front of the radiator.

Abstract: To concentrate mass, to lower the center of gravity, to efficiently and optimally arrange an intake part for making a compact vehicle body. A cylinder inclined to the rear is arranged under a fuel tank and a body of an intake box is housed between a radiator arranged in front of the cylinder and the cylinder. An upper part of the body of the intake box is fixed to a body frame at the bottom of the fuel tank and air taken in is supplied to an intake port through an intake funnel and a throttle body respectively built-in. A lid of an intake duct can be extractably inserted into a window hole provided to the front of the body, a duct part integrated with the lid is arranged over the radiator, and an air intake guide port takes a flow of air in front of the radiator.

Abstract: An air intake structure for a motorcycle includes a pair of hollow laterally spaced frames extending from a headpipe to a rear portion of the motorcycle, a hollow cross member connecting the frames together at an intermediate portion thereof, wherein the hollow interior of the cross member communicates with the hollow interiors of the frames. Intake openings are provided at a front portion of the frames for feeding air into the frames, while an exhaust opening is formed on the bottom of the cross member for exhausting air downward to the engine air intakes. A fuel tank cover is provided to cover a flexible fuel tank disposed between the laterally spaced hollow frames. The fuel tank cover includes a hollow fairing stay formed integrally therewith for supporting a motorcycle fairing, wherein the hollow fairing stay forms an air duct for directing air from an air inlet in the fairing to the intake openings of the frame.

Abstract: For at least a portion of a body frame, a pipe member is used, which includes therein a longitudinal partition wall for defining passages. The pipe member is provided with an inlet and an outlet to be in communication with the passages. A plurality of passages defined in the pipe member are used for various purposes including cable insertion passages, engine breeder passages or air feeding passages.

Abstract: A frame material for a motor vehicle comprising a structure having an elongated hollow body of a rectangular cross section and a honeycomb member having a multiplicity of independent chambers and arranged in the hollow body such that central axes of the chambers are directed substantially perpendicularly to longer sides of the rectangular cross section of the hollow body. A frame construction for use in a motor vehicle includes the frame material as a main frame interconnecting a head pipe and a rear fork pivot rectilinearly in side elevation.

Abstract: This disclosure relates to apparatus for preventing the nose dive produced when a motorcycle is sharply braked. The motor cycle includes a frame, front and rear wheels, and front and rear mounting means for connecting the wheels to the frame. The anti-nose-dive apparatus includes a generally U-shaped torsion bar having a center portion and front and rear arms. The center portion is rotatably mounted on the frame, the front arm is connected to the front mounting means, and the rear arm is connected to the rear mounting means. When the vehicle is moving and is sharply braked, the front end of the frame tends to move down relative to the front wheel. This action twists the torsion bar causing the rear mounting means to tend to rise. The reaction on the torsion bar causes the rear end of the frame to move down relative to the rear wheel, thereby reducing the amount of the nose dive.