Abstract: A motorcycle includes a frame having a front, a rear, a top, a bottom, and a centrally-located longitudinal axis extending through the front and the rear. The longitudinal axis defines a vertical plane. An engine is supported by the frame. A radiator coil is coupled to the frame and spaced apart from the vertical plane. A shroud is coupled to the frame and at least partially surrounds the radiator coil. The shroud directs an airflow through the radiator coil and toward the vertical plane as the airflow passes in the rearward direction. The shroud directs the airflow downwardly as the airflow passes through the radiator coil in the rearward direction.

Abstract: A motorcycle frame includes hollow left and right frame members that define a fuel-containing volume. Left-center, right-center, left-rear, and right-rear engine supports each depend from a corresponding left and right frame member. Each engine support includes a first portion that is coupled to the frame member and a second portion that is coupled to the engine. Each engine support also includes a stress riser defined between the first and second portions. The stress riser is configured to cause the first and second portions to separate from one another in response to application of sufficient force to the engine or second portion. By causing the first and second portions of the engine mount to separate in a predetermined way, the frame members and the fuel-containing volume are left intact.

Abstract: A motorcycle including a frame having a top, a bottom, a front, a rear, and a centrally-located longitudinal axis extending through the front and the rear. The longitudinal axis defines a vertical plane. The motorcycle also includes an engine supported by the frame and a radiator coil obliquely mounted to the frame. The radiator coil is spaced apart from the vertical plane and includes a forward end and a rearward end as viewed from above the motorcycle. The forward end defines a first distance measured normal to the vertical plane and the rearward end defines a second distance measured normal to the vertical plane. The first distance is shorter than the second distance.

Abstract: A motorcycle frame includes hollow left and right frame members that define a fuel-containing volume. Left-center, right-center, left-rear, and right-rear engine supports each depend from a corresponding left and right frame member. Each engine support includes a first portion that is coupled to the frame member and a second portion that is coupled to the engine. Each engine support also includes a stress riser defined between the first and second portions. The stress riser is configured to cause the first and second portions to separate from one another in response to application of sufficient force to the engine or second portion. By causing the first and second portions of the engine mount to separate in a predetermined way, the frame members and the fuel-containing volume are left intact.

Abstract: A motorcycle including a frame having a top, a bottom, a front, a rear, and a centrally-located longitudinal axis extending through the front and the rear. The longitudinal axis defines a vertical plane. The motorcycle also includes an engine supported by the frame and a radiator coil obliquely mounted to the frame. The radiator coil is spaced apart from the vertical plane and includes a forward end and a rearward end as viewed from above the motorcycle. The forward end defines a first distance measured normal to the vertical plane and the rearward end defines a second distance measured normal to the vertical plane. The first distance is shorter than the second distance.

Abstract: An air intake assembly for an engine of a motorcycle includes an air intake opening for receiving intake air, the intake air defining an air flow direction. The air intake assembly further includes an airbox at least partially defining a chamber. A partition is positioned within the chamber dividing the chamber into an expansion chamber in communication with and downstream of the air intake opening and a sub-chamber configured to reduce the noise associated with the flow of intake air through the air intake assembly during operation of the engine.

Abstract: An exhaust system for a motorcycle engine includes a muffler assembly. The muffler assembly includes a downstream attenuation portion adapted to be positioned substantially rearward of the motorcycle engine and having a first height, an upstream portion adapted to be positioned substantially forward of the motorcycle engine and having a second height, and an intermediate attenuation portion between the upstream portion and the downstream attenuation portion. The intermediate attenuation portion is adapted to be positioned substantially below the motorcycle engine and has a third height less than half the first height. In some embodiments, a motorcycle is provided, in which the motorcycle engine is positioned substantially within a recess of the muffler assembly to a depth greater than the third height.

Abstract: A motorcycle having at least two wheels, a fuel tank for storing fuel, a fuel pump positioned in an opening in the fuel tank, and a retaining clip (e.g., a snap ring, circlip, a cotter pin, a hair pin, a clevis pin, a roll pin, an e-clip, a c-clip, a retainer spring, or a toothed washer) securing the fuel pump in the opening. In one embodiment, the opening is adapted to receive the fuel pump in an axial direction, and the opening is formed by a seal surface (e.g., substantially cylindrical in shape) that is substantially parallel to the axial direction. In this embodiment, the fuel pump includes a pump housing and a gasket (e.g., an O-ring) positioned between the pump housing and the seal surface.