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: An air cleaner system for motorcycles employing the hollow interior of a main frame member. A U-shaped cavity facing forwardly of the motorcycle in the fuel tank allows access to the air cleaner assembly positioned within the main frame member. An inlet opening is provided on the upper surface of the main frame member while outlet openings on the lower surface thereof extend to carburetors. The inlet opening of the main frame member is reinforced and a baffle is positioned between the air filter assembly and the intake passages to the carburetors.

Abstract: A motor vehicle with a riding saddle has a frame including a main pipe employed as an air intake passage for supplying air to an air cleaner. The main pipe has an air inlet defined in its front end. An air guide member is disposed on one side of the main pipe for introducing external air into the air inlet, and a radiator for cooling a water-cooled engine is disposed on the other side of the main pipe.

Abstract: An air intake passage formed inside a main pipe which constitutes a portion of a body frame of a vehicle. An air chamber which provides communication between the air intake passage and an air cleaner is formed by utilizing the inside of a gusset which is provided to reinforce the connection between the main pipe and a pair of center pipes extending rearwardly from the main pipe on the right and left sides, respectively.

Abstract: A tricycle having at least one front wheel and a front fork carrying the front wheel, fuel and oil tanks positioned at the rear of the front fork, comprising at least one longitudinal frame elongated in a longitudinal direction of the tricycle and securely connected at its foremost end to the front fork structure, the fuel and oil tanks being supported on a front portion of the frame, and a rear fender structure having a front tank cover portion and at least one rear fender portion which merges rearwardly out of the front tank assembly cover portion and which is pivotally connected to the frame in the neighborhood of the rear end of the frame so that the rear fender structure as a whole is pivotally movable between a lower angular position resting on the frame and having the fuel and oil tank assemblies enclosed within the tank cover portion and an upper angular position raised above the frame and the tanks.

Abstract: An exhaust system of a two-cycle engine mounted on a motorcycle is provided with a subchamber branching off from the exhaust pipe. The subchamber is disposed by utilizing a so called dead space in the frame of the motorcycle, particularly in a position in front of the engine and between a pair of cradle pipes of a body frame on which the engine is mounted. With this arrangement, it becomes possible to layout the position of the subchamber without altering the configuration of the body frame, and there is further advantage that the subchamber is well protected by the structural members.

Abstract: An offroad auto tricycle embodying an improved air inlet to prevent the ingestion of foreign material and particularly water into the engine induction system. The air inlet device includes an elongated air inlet tube that has its inlet end positioned in proximity to and beneath the forwardmost portion of the seat for protecting the air inlet from foreign matter.

Abstract: An air intake system in a motorized cycle of the type wherein a fuel tank is disposed behind a top bridge. Within the fuel tank is formed an outside air introducing path having an opening formed in the front portion of the tank, with an air cleaner being disposed downstream of the outside air introducing path. With such arrangement, a relatively large flow of air can be introduced with a relatively small load on the air cleaner.

Abstract: An improved body frame with a liquid tank secured integrally thereto for a motorcycle is disclosed which is constructed such that at least a part of the body frame is constituted of a pipe member. The improvement consists in that the liquid tank serving as an oil tank or the like is constituted by a combination of a main pipe fixedly connected to a head pipe and a gusset fixedly secured to said main pipe. The liquid tank includes a first holding chamber and a second holding chamber which are in communication with one another, said first holding chamber being defined by a combination of a part of the main pipe and the gusset, while said second holding chamber being defined by the inside space of the main pipe. Further, the liquid tank includes a defining chamber having a small holding capacity which is communication therewith, said defining chamber being equipped therein with a surface level detecting unit by means of which the surface level of liquid in the liquid tank is detected.

Abstract: A vehicle fuel tank including a fuel level detector positioned within the fuel tank, the fuel level detector being connected to a base means which is positioned so as to fit in sealing relationship about a fuel level detector aperture formed within the vehicle fuel tank. The vehicle fuel tank is provided with a mounting bracket secured to the vehicle fuel tank about the fuel level detector aperture and means are provided for fastening the base means to the mounting bracket. Preferably, a sealing means is positioned between the base means and the fuel tank.

Abstract: An air cleaner is provided on an upstream end portion of an intake air passage of an engine of a motorcycle and is fixed inside a fairing on the motorcycle ahead of the engine. The air intake opening of the air cleaner is directed inwardly of the fairing and can be positioned below the fuel tank. The air cleaner is provided on the inside of the fairing member opposite to a side stand on the motorcycle.

Abstract: An motorcycle has a body frame supporting an engine and provided with a seat. A leg shield on the body frame covers the front of the lower legs of a rider sitting on the seat. A main pipe of the body frame extends between the leg shield and the seat. An air cleaner for the engine has suction ports located on the internal side of the leg shield facing the seat, in order to exclude from the suction ports ram air produced by forward motion of the motorcycle. Two intake pipes straddle the main pipe and connect the suction ports to the air cleaner.

Abstract: An air cleaner system for a motorcycle having a single shock absorber disposed between an engine and a rear wheel so as to be close to the center of gravity of the vehicle body. The air cleaner system includes substantially one casing having an air intake opening and an air cleaner element provided therein, the casing being disposed between the engine and rear wheel substantially surrounding at least part of the shock absorber. The relatively large space between the engine and rear wheel is thus effectively utilized such that the air cleaner system has a desirably large capacity for supplying air to a multiple-cylinder, multiple-carburetor engine, and at the same time good maneuverability and high stability of the motorcycle is ensured.

Abstract: Air cleaner for a motorcycle is disposed in an internal space of a hollow fairing of the motorcycle, and is communicatively connected with a carburetor of an engine of the motorcycle through a conduit pipe.

Abstract: A two-wheeled motorcycle includes a shell made of thin plates to the front end of which a head pipe is fixed. The shell is opened at its rear side and a rear wheel driving power unit is accommodated by and fixed to the shell. A seat stay carrying a rider's seat and covering the upper part of the rear wheel is pivotally secured at its front end to the shell so as to be rotated upward. A fuel tank is disposed ahead of the rider's seat and pivotally secured at its front end to the shell so as to be rotated upward.

Abstract: A motorcycle has an engine with two banks of cylinders. One bank is forward of the other, and its exhaust pipe or pipes passes forwardly, downwardly, and outwardly of the frame, and then rearwardly beneath the side of the engine to reach a muffler and tailpipe. The frame includes a pivoted fork-like rear section with a power transmission. The rear exhaust pipe or pipes extends rearwardly and downwardly between the arms of the rear section, and makes connection with the muffler. In another embodiment for engines with multiple cylinders in each bank, the rear exhaust pipes cross over one another, and extend downwardly outside of the arms. They may also be elongated inside the muffler so the lengths of the forward and rear exhaust pipes are equal. They can connect with one another so as to share outlets into the muffler.

Abstract: A motorcycle engine having a V-shaped cylinder arrangement in which a space is defined between the fore and aft cylinders. Carburetors for the fore and aft cylinder are disposed in the space between the cylinders and an air filter is located behind the engine. The motorcycle has a frame which is formed with an inside cavity connected with the air filter and the carburetors so that the inside cavity constitutes a part of the intake passage.

Abstract: A frame for a motorcycle is disclosed of the type including a main frame which extends rearwardly and downwardly from the journal for the steerable front wheel, and, which at its lower end is rigidly attached to a casing of the drive motor. In order to provide space for accommodating an air filter and ancilliary equipment, a pair of subsidiary tubes are rigidly attached to an upper portion of the main frame, the subsidiary tubes respectively diverging outwardly from the main frame and then extending rearwardly and downwardly to a rigid attachment with a transverse tubular member which is rigidly attached to a rear lower end of the main frame, the attachment of the subsidiary tubes to the tubular member being at positions spaced outwardly of the main frame.

Abstract: A motorized bicycle which features a removable fuel tank. The fuel tank may be selectively secured within a housing mounted on the frame of the bicycle. The housing and tank include means which cooperate upon insertion of the fuel tank to permit fuel to flow from the tank to the fuel line for the engine of the bicycle. Removal of the tank from the housing automatically seals the tank against spillage of fuel and permits the bicycle to be safely transported. The fuel tank also features an air vent which is automatically opened when the tank is secured in the housing.

Abstract: A land vehicle such as a motorcycle has a frame and seat which, when the seat is in a normal operating position, define between themselves a space which is substantially closed and substantially inaccessible. A structure which includes components such as electronic components is situated in this latter space so as to be protected from the outer atmosphere and from unauthorized access when the seat is in its normal operating position. By way of a suitable connecting structure the seat can be displaced from its normal operating position to a location where the seat is at least partially spaced from the frame to give access to the space where the structure which includes electronic components or the like is situated, so that access may be had to the structure for servicing or the like.

Abstract: A motorcycle has an engine with two banks of cylinders. One bank is forward of the other, and its exhaust pipe or pipes passes forwardly, downwardly, and outwardly of the frame, and then rearwardly beneath the side of the engine to reach a muffler and tailpipe. The frame includes a pivoted fork-like rear section with a power transmission. The rear exhaust pipe or pipes extends rearwardly and downwardly between the arms of the rear section, and makes connection with the muffler. In another embodiment for engines with multiple cylinders in each bank, the rear exhaust pipes cross over one another, and extend downwardly outside of the arms. They may also be elongated inside the muffler so the lengths of the forward and rear exhaust pipes are equal. They can connect with one another so as to share outlets into the muffler.

Abstract: A motorcycle engine having a V-shaped cylinder arrangement in which a space is defined between the fore and aft cylinders. Carburetors for the fore and aft cylinder are disposed in the space between the cylinders and an air filter is located behind the engine. The motorcycle has a frame which is formed with an inside cavity connected with the air filter and the carburetors so that the inside cavity constitutes a part of the intake passage.