A mounting structure of an exhaust pipe system in a vehicle capable of making a magnitude of a moment acting on the exhaust pipe system as small as possible by means of a simple constitution. In a mounting structure of an exhaust pipe system in a vehicle the exhaust pipe system is connected to an engine loaded onto the vehicle and for guiding exhaust gas discharged from the engine to the ambient air, on a vehicle body frame constituting the vehicle, wherein the exhaust pipe system is constituted so as to be connected to the vehicle body frame in a position substantially upwardly from a position G of the center of gravity of the exhaust pipe system.

A vehicle body frame structure for a two-wheeler provides a sufficient distance between exhaust pipes and a front wheel, to facilitate the arrangement of a heat-discharging member such as a radiator or an oil cooler, or other auxiliary components, to increase heat-discharging property by increasing the capacity of the heat-discharging member, and improving flexibility in design such as the shape or the layout of the vehicle body frame and the exhaust pipes. In a two-wheel vehicle having an engine mounted to a vehicle body frame, the engine having exhaust pipes extending forwardly and downwardly and a pair of left and right down tubes extending substantially downwardly from a head pipe provided at the front end of the vehicle body frame, the vehicle body frame includes a first cross member for connecting the left and right down tubes, and the first cross member is formed with arcuate recesses for allowing part of the exhaust pipes to pass therethrough.