Patent ID: 7258186
Filing Date: 2007-08-21
Classification: B62K

Abstract:
1. A vehicle frame structure for a motorcycle, which comprises: a head block including a head tube; a main frame welded to the head block and forked leftwards and rightwards from the head block including a pair of left and right inner frame halves positioned inside the vehicle frame structure and a pair of left and right outer frame halves positioned outside the vehicle frame structure; and swing arm brackets extending downwardly from rear ends of the main frame; wherein the inner and outer frame halves of the main frame are respectively configured to have generally U-shaped sections, with their openings welded to each other to form the main frame, wherein the inner frame halves of the main frame and the swing arm brackets, in their entirety or respective inner portions of the swing arm brackets, are made of a unitary cast metal, wherein at least the outer frame halves of the main frame are made of a sheet metal, and wherein a guide passage for introduction of air to an air cleaner of an engine is formed inside the main frame.