Frame structure null of saddle riding die car

摘要

PURPOSE:To provide frame structure which is reduced in its weight and improved in its rigidity by forming loop-form closed curved surface to the sides on both sides of a car body frame, forming different curved surface in the closed curved surface, and disposing the pivot part of a suspension to an auxiliary member of which the closed curved surface is formed. CONSTITUTION:A square and loop-form first closed curved surface S0 is formed on the sides on both sides of a car body frame 10 of an astride type vehicle by means of a tank tail tune 13 and a side member 15. A square second closed curved surface S1 the one side of which is the front side (a front pipe 15a3) of the first closed curved surface S0 and the other side of which is a frame tube 17 and the lower side (a lower pipe 15a2) of the second closed curved surface S0 is formed in the first closed curved surface S0. An auxiliary member is composed of a frame tube 17 in cooperation with a lower side 161 of a side bridge tube 16. The support arm of a front suspension, not shown in the figure, is supported to the auxiliary member, and the front end part of an engine, not shown in the figure, is supported through a bracket.