Abstract: A motorcycle body frame structure improves rigidity and further suppresses changes in vehicle body behavior. The body frame structure includes: a head pipe, right and left main frames connected to the head pipe, a down tube connected to the head pipe, right and left reinforcing frames installed between the down tube and corresponding right and left reinforcing frames. Each of the right and left reinforcing frames include a first and second joint portions joined to the down tube. The first joint portions are joined with corresponding right and left main frames. Each of the second joint portions include a first joint flange portion welded with corresponding right and left side surfaces of the down tube, a second joint flange portion welded with an upper surface of the down tube, and a third joint flange portion connected with the first and second joint flange portions and separated from the down tube.

Abstract: A master cylinder device 38 for a rear wheel brake of a motorcycle includes a master cylinder 35 and a reserve tank 36. The cylinder 35 discharges brake fluid when a piston thereof is pushed by depression of a brake pedal 40. The reserve tank is integrally formed with a cylinder body 35a of the master cylinder 35. A contour 60 of a rear wheel side of the master cylinder device 38 extending continuously from a bottom end ? of the master cylinder body 35a in a vertical direction to an upper end ? of the reserve tank 36 in the vertical direction is linearly formed to be oriented obliquely rearward and upward in a vehicle side view.

Abstract: A master cylinder device 38 for a rear wheel brake of a motorcycle includes a master cylinder 35 and a reserve tank 36. The cylinder 35 discharges brake fluid when a piston thereof is pushed by depression of a brake pedal 40. The reserve tank is integrally formed with a cylinder body 35a of the master cylinder 35. A contour 60 of a rear wheel side of the master cylinder device 38 extending continuously from a bottom end ? of the master cylinder body 35a in a vertical direction to an upper end ? of the reserve tank 36 in the vertical direction is linearly formed to be oriented obliquely rearward and upward in a vehicle side view.

Abstract: A motorcycle body frame structure improves rigidity and further suppresses changes in vehicle body behavior. The body frame structure includes: a head pipe, right and left main frames connected to the head pipe, a down tube connected to the head pipe, right and left reinforcing frames installed between the down tube and corresponding right and left reinforcing frames. Each of the right and left reinforcing frames include a first and second joint portions joined to the down tube. The first joint portions are joined with corresponding right and left main frames. Each of the second joint portions include a first joint flange portion welded with corresponding right and left side surfaces of the down tube, a second joint flange portion welded with an upper surface of the down tube, and a third joint flange portion connected with the first and second joint flange portions and separated from the down tube.

Abstract: A head pipe of a vehicle body frame includes an upper side head pipe with a pair of upper and lower facing piece parts extending from an upper side pipe part so as to fit to upper and lower wall portions of a pair of right and left main frames, a lower side head pipe with a lower side pipe part joined to the upper side pipe part and a front side tongue piece part extending from the lower side pipe part so as to fit to a front wall portion of a down frame, and a reinforcing member joined to a rear portion of the upper side head pipe and having a rear side tongue piece part extending so as to fit to a rear wall portion of the down frame from a vertical wall part positioned between inner side wall portions of the main frames.

Abstract: A head pipe of a vehicle body frame includes an upper side head pipe with a pair of upper and lower facing piece parts extending from an upper side pipe part so as to fit to upper and lower wall portions of a pair of right and left main frames, a lower side head pipe with a lower side pipe part joined to the upper side pipe part and a front side tongue piece part extending from the lower side pipe part so as to fit to a front wall portion of a down frame, and a reinforcing member joined to a rear portion of the upper side head pipe and having a rear side tongue piece part extending so as to fit to a rear wall portion of the down frame from a vertical wall part positioned between inner side wall portions of the main frames.