JP2012218586A - Motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique with which a steering damper can be compactly arranged in a motorcycle.SOLUTION: A steering damper 25 is arranged below a main frame 26 extending a longitudinal axis in a vehicle longitudinal direction, and at least a part of the steering damper 25 is arranged at a position overlapping the main frame 26. A front fork 18 is supported only by a bottom bridge 19. The main frame 26 is a square frame whose cross section is rectangular, and a frame side connection part 90 connecting the main frame 26 and the steering damper 25 is provided on a side face 82L of the main frame 26.

Description

  The present invention relates to an improvement of a motorcycle provided with a steering damper.

  2. Description of the Related Art A motorcycle is known that includes a steering damper that attenuates a rotational fluctuation of a steering system that a front wheel receives (see, for example, Patent Document 1 (FIG. 1)).

  As shown in FIG. 1 of Patent Document 1, a steering shaft (2) is supported at the front end of the frame (3) (the numbers in parentheses indicate the symbols described in Patent Document 1. The same applies hereinafter) so that the steering shaft (2) can turn left and right. A front fork (1) is attached to the steering shaft (2), and a damper cylinder (5) for a steering damper is provided at the left end of the front fork (1). The damper shaft (7) is extended so that it can extend and contract. The damper shaft (7) is attached to the inner surface of the upper left tube (8) through a through hole (9) opened in the frame (3).

In the structure of Patent Document 1, the damper cylinder (5) attached to the left end portion of the hawk (1) is disposed away from the main frame. In other words, the main portion of the steering damper is disposed at a position away from the main frame in a plan view of the vehicle, so that the space occupied by the steering damper increases in the vehicle width direction.
Therefore, a technique capable of arranging the steering damper in a compact manner is desired.

Japanese Utility Model Publication No. 5-26779

  An object of the present invention is to provide a technique capable of compactly arranging a steering damper in a motorcycle.

  According to the first aspect of the present invention, a vehicle body frame is provided with a head pipe and a main frame extending from the head pipe to the rear of the vehicle, and a steering stem is pivotally supported by the head pipe. A bottom bridge is provided, and a front fork that rotatably supports the front wheels is supported on the bottom bridge, and the steering system receives fluctuations in the steering system due to the expansion and contraction of the rod extending from the damper chamber between the bottom bridge and the vehicle body frame. In a motorcycle in which a damping damper to be damped is interposed, the main frame is a mono-backbone frame, and the steering damper is disposed below the main frame so that the longitudinal axis of the steering damper extends in the longitudinal direction of the vehicle. And at least in plan view of the vehicle Wherein a portion of the steering damper is disposed at a position overlapping the main frame.

  The invention according to claim 2 is characterized in that the front fork is supported only by the bottom bridge.

  In the invention according to claim 3, the main frame is a rectangular frame having a rectangular cross section composed of left and right side surfaces, an upper surface passed to the upper ends of the left and right side surfaces, and a lower surface passed to the lower ends of the left and right side surfaces, The frame side connecting portion that connects the main frame and the steering damper is provided on one of the left and right side surfaces.

  In the invention according to claim 4, the bottom bridge side connecting portion that connects the bottom bridge and the steering damper extends from the rear portion of the bottom bridge to the rear of the vehicle. In the neutral position, it is arranged at a position overlapping with the main frame.

  The invention according to claim 5 is characterized in that the bottom bridge side connecting portion is a tapered member whose cross-sectional area becomes smaller toward the tip with respect to the base portion.

  The invention according to claim 6 is provided with an engine as a drive source in which the cylinder shaft extends horizontally in the body frame, and an intake system that supplies outside air to the engine above the engine and below the steering damper. It is provided.

  In the invention according to claim 7, the main frame is formed to be bent through the bent portion, and has a V shape that opens upward in a side view of the vehicle, and includes the lowest point of the bent portion and the lower end of the bottom bridge. A steering damper is arranged in a space above the connecting line and below the main frame.

  The invention according to claim 8 is characterized in that a side cover that covers the side of the main frame extends downward, and the side of the steering damper is covered with the side cover.

  In the invention according to claim 1, the steering damper is disposed below the main frame such that its longitudinal axis extends in the longitudinal direction of the vehicle, and at least a part of the steering damper overlaps with the mono-backbone main frame. Placed in.

  Compared to the case where the steering damper does not overlap the main frame, a part of the steering damper is arranged at a position overlapping the mono-backbone main frame, so the steering damper can be arranged compactly in the vehicle width direction. it can.

In the invention according to claim 2, the front fork is supported only by the bottom bridge.
The bottom bridge is below the head pipe. By attaching the upper end of the front fork to such a bottom bridge, there is no front fork above the bottom bridge. Since there is no front fork around the head pipe, it is possible to increase the degree of freedom of component arrangement around the head pipe where space is limited.

In the invention according to claim 3, the frame side connecting portion is provided on one of the left and right side surfaces of the main frame.
Compared to the case where the frame side connecting part that connects the steering damper and the main frame extends downward from the lower surface of the main frame, the fixed part of the steering damper can be arranged on the side of the main frame, and that much The steering damper can be arranged closer to the main frame. If the steering damper can be arranged close to the main frame, the degree of freedom of arrangement of the engine accessories below the main frame can be increased.

  In addition, the main frame having a rectangular cross section has a larger amount of deformation on the upper and lower surfaces than on the left and right side surfaces. Since the frame side connecting portion is provided on one of the left and right side surfaces with a small amount of deformation compared to the upper surface and the lower surface, the influence on the rigidity to the main frame can be suppressed low.

  In the invention which concerns on Claim 4, when a front wheel is a left-right neutral position, the bottom bridge side connection part has overlapped with the main frame. Since the bottom bridge side connecting portion overlaps the main frame at the neutral position, the amount of protrusion in the vehicle width direction during left turning and the amount of protrusion in the vehicle width direction during right turning can be made substantially the same. Since it does not protrude greatly only to the left or right, the amount of protrusion can be leveled, and as a result, the amount of protrusion of the steering damper to the side of the main frame in the vehicle width direction can be kept small.

  In the invention which concerns on Claim 5, a bottom bridge side connection part is a taper-shaped member with which a cross-sectional area becomes small toward a front-end | tip with respect to a base. That is, the cross-sectional area of the base where the highest stress is generated is increased, and the cross-sectional area is sequentially decreased from the base so that the cross-sectional area of the tip is minimized. Since the cross-sectional area of the member is changed according to the magnitude of the stress generated by the part, the bottom bridge side connecting portion can be reduced in size.

  In the invention according to claim 6, the intake system is provided above the engine and below the steering damper. A steering damper and an intake system are arranged above the main frame above the engine with large space constraints. As a result, the vehicle as a whole can be made compact.

  In the invention according to claim 7, the steering damper is disposed in a region surrounded by a main frame and a line connecting the lower portion of the V-shaped portion and the lower end of the steering stem. The steering damper can be efficiently arranged using an area that tends to be a dead space below the main frame.

  In the invention according to claim 8, since the side of the steering damper is covered with the side cover that covers the side of the main frame, the steering damper can be protected by the side cover.

1 is a left side view of a motorcycle according to the present invention. It is the figure which removed the vehicle body cover etc. from FIG. It is a principal part side view of FIG. It is a figure explaining a steering damper and the structure of the vicinity. It is a top view of a steering damper. It is a top view of the stay member extended from the bottom bridge. It is a rear view of the stay member extended from the bottom bridge. It is sectional drawing explaining the support structure of the swing arm by a pivot part. It is action explanatory drawing of the steering damper which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described in detail. In the drawings and examples, “up”, “down”, “front”, “rear”, “left”, and “right” respectively indicate directions viewed from the driver who rides the motorcycle. The drawings are viewed in the direction of the reference numerals.

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a motorcycle 10 is provided with a body frame 11, and a front wheel steering system 13 is rotatably supported by a head pipe 12 that constitutes the front end of the body frame 11.
The vehicle body frame 11 is covered with a vehicle body cover 20, which includes a front cowl 21 that covers the front wheel steering system 13 at the front of the vehicle and the front of the vehicle, and a handle that covers the handle 15 at a position above the front cowl 21. It consists of a cover 22 and a plurality of side covers 23a to 23d covering the side of the vehicle.

  The front wheel steering system 13 includes a steering stem 16 that is pivotally supported by the head pipe 12, a bottom bridge 19 that is attached to the lower end of the steering stem 16 and supports a front fork 18 that supports the front wheel 17, and the steering stem 16. And a steering handle 15 which is attached to the upper end of the vehicle and operated by the occupant.

  In the front wheel steering system 13 of the present invention, the front fork 18 is not extended to above the head pipe 12. Therefore, there is no so-called top bridge that supports the front fork 18 above the head pipe 12 (upper position). That is, the front fork 18 is supported only by the bottom bridge 19.

  The bottom bridge 19 is provided below the head pipe 12. By attaching the upper end portion 18 a of the front fork to the bottom bridge 19, the front fork 18 does not exist above the bottom bridge 19. Since the front fork 18 does not exist around the head pipe 12, the degree of freedom of component arrangement around the head pipe 12 where space is limited can be increased.

  A steering damper 25 is interposed between the bottom bridge 19 and the main frame 26 constituting the vehicle body frame 11 to alleviate a rapid turning force applied to the steering stem 16.

Next, a description will be given of a vehicle body frame or the like that constitutes the skeleton of the vehicle and supports the vehicle body parts.
As shown in FIG. 2, the vehicle body frame 11 includes a head pipe 12, a main frame 26 that extends rearward and obliquely downward from the head pipe 12, and a pivot plate that hangs downward from the rear end of the main frame 26. 27 and a seat rail 28 extending obliquely upward and rearward from the rear portion of the main frame 26 are main elements. A cowl stay 31 that supports a front cowl (reference numeral 21 in FIG. 1) extends from the head pipe 12 to the front of the vehicle. The main frame 26 is a mono backbone frame.
A gusset member 32 is passed between the head pipe 12 and the main frame 26, and an auxiliary frame 33 is extended from the pivot plate 27 to an intermediate portion of the seat rail 28.

  The engine 36 includes an engine main body 41 that includes a crankcase 37 having a built-in transmission, a cylinder block 38 including a cylinder block 38 extending from the crankcase 37 forward of the vehicle, and a cylinder head 39. The crankcase 37 of the engine body 41 is suspended from the main frame 26 via first and second support portions 43a and 43b, and is suspended from the pivot plate 27 via a third support portion 43c.

  An intake system 50 is connected to the upper surface 39a of the cylinder head. The intake system 50 includes an intake pipe 52 extending from the cylinder head 39, a throttle body 51 connected to the intake pipe 52, and an intake funnel 53 as an air intake port attached to the front portion of the throttle body 51. ing.

  That is, the body frame 11 is provided with an engine 36 as a drive source in which a cylinder shaft 55 extends substantially horizontally, and an intake system 50 for supplying outside air is provided above the engine 36. The intake system 50 is provided below the steering damper 25.

  Returning to FIG. 1, a rear wheel 57 as a drive wheel driven by the engine 36 is provided at the rear end of the swing arm 58, and the swing arm 58 is swingably supported between the swing arm 58 and the seat rail 28. The seat 62 on which the occupant sits is placed, the front fender 63 is attached to the front fork 18 at a position above the front wheel 17, and the rear wheel 57 is positioned obliquely above and behind the rear wheel 57. The rear fender 64 is attached to the seat rail 28. A headlight 65 is attached to the front surface of the front cowl 21, and a taillight 66 is attached to the rear end of the side cover 23c.

Side covers 23 a and 23 b attached to the main frame 26 cover the sides of the main frame 26. A side cover 23a that covers the side of the main frame 26 extends downward, and the side of the steering damper 25 is covered by the side cover 23a.
Since the side of the steering damper 25 is covered with the side cover 23a, the steering damper 25 can be protected by the side cover 23a.

  A space S is provided below the side cover 23a, and the side cover 23b is disposed below the space S. It is also possible to adjust the steering damper 25 using this space S. An opening for adjusting the steering damper may be provided in the side cover.

Next, the arrangement structure of the steering damper will be described.
As shown in FIG. 3, a bottom bridge 19 is provided at the lower portion of the steering stem 16, and a front fork 18 that rotatably supports a front wheel (reference numeral 17 in FIG. 2) is supported on the bottom bridge 19. A steering damper 25 is interposed between the main frame 26 of the frame 11. A telescopic rod 71 is extended to the steering damper 25, and a bottom bridge 19 is attached to the tip of the rod 71, and a front wheel steering system 13 (also referred to as “steering system 13”) received by the front wheels 17. Attenuates dynamic fluctuations.

  The main frame 26 is bent through a bent portion 26c, has a V-shape that opens upward in a side view of the vehicle, and connects a line L connecting the lowest point 81 of the bent portion 26c and the lower end 19b of the bottom bridge. A steering damper 25 is disposed in the space below the main frame 26 above.

Next, the structure of the connecting portion of the steering damper will be described.
As shown in FIG. 4, the main frame 26 has left and right side surfaces 82L and 82R (only the reference numeral 82L on the front side in the figure is shown), and an upper surface 83 extending in the vehicle width direction at the upper ends of these left and right side surfaces 82L and 82R. And a rectangular frame having a rectangular cross section, which is composed of a lower surface 84 extending in the vehicle width direction at the lower ends of the left and right side surfaces 82L and 82R.

Next, the frame side connecting portion will be described.
The frame side connecting portion 90 includes a plate-like member (plate portion 93) that connects the main frame 26 and the steering damper 25. The frame side connecting portion 90 is attached to one left side 82 </ b> L of the left and right side surfaces of the main frame 26 by a plurality of fastening members 91.

  The frame side connecting portion 90 includes a plate-like plate portion 93 and a cylindrical member 94 as a fastening portion fixed to the lower portion of the plate portion 93. A threaded portion 95 is formed on the inner surface 94b of the cylindrical member, and a fastening bolt 96 to which the rear portion 25b of the steering damper is attached is screwed into the threaded portion 95. A spherical bearing 97 is interposed between the fastening bolt 96 and the rear portion 25b of the steering damper. The spherical bearing 97 enables the steering damper 25 to follow the twisting and bending forces applied to the steering damper 25.

The frame side connecting portion 90 is fastened to the left side surface 82L.
If the frame-side connecting portion 90 is extended downward from the lower surface 84 located at the center in the vehicle width direction, the screw portion that becomes the fastening portion moves downward, and the steering portion moves as the screw portion moves downward. The position of the damper 25 also moves downward.

  In this regard, in the present invention, since the fastening portion is provided on the side surface of the main frame 26, it is possible to increase the length of the fastening portion, and it is not necessary to move the fastening portion downward. As a result, the steering damper 25 can be disposed close to the main frame 26, and a limited space can be effectively utilized.

  That is, the frame side connecting portion 90 is provided on the left side surfaces 82L and 82R of the left and right side surfaces 82L and 82R of the main frame 26. The steering damper 25 can be disposed closer to the main frame 26 as compared with the case where the frame side connecting portion 90 extends downward from the side surfaces 82L and 82R of the main frame. If the steering damper 25 can be disposed close to the main frame 26, the degree of freedom of arrangement of the engine accessories below the main frame 26 can be increased.

The main frame 26 having a rectangular cross section has a larger input load on the upper surface 83 and the lower surface 84 than on the left and right side surfaces 82L and 82R. Since the frame side connecting portion 90 is provided on the left side surface 82L of the left and right side surfaces 82L and 82R having a small input load, the influence on the rigidity to the main frame 26 can be kept low.
The frame side connecting portion may be provided on the right side surface of the main frame.

Next, the bottom bridge connecting portion will be described.
The bottom bridge side connecting portion 100 includes a plate-shaped molded member 103 extending from the rear portion 19c of the bottom bridge to the rear of the vehicle, and a cylindrical member 104 serving as a fastening portion fixed to the rear end portion of the molded member 103. . A threaded portion 105 is formed on the inner surface 104b of the cylindrical member, and a fastening bolt 106 to which the front portion 25a of the steering damper is attached is screwed into the threaded portion 105. A spherical bearing 107 is interposed between the fastening bolt 106 and the front portion 25a of the steering damper. The spherical bearing 107 enables the steering damper 25 to follow the twisting and bending forces applied to the steering damper 25.

  The bottom bridge side connecting portion 100 is provided with a forming member 103 as a plate-like member connected to the bottom bridge 19 and the steering damper 25. The cylindrical member 104 is fixed to the rear portion 19c of the bottom bridge by welding.

Next, the structure of the steering damper will be described.
As shown in FIG. 5, the steering damper 25 includes a damper chamber 72, a sub-tank 73 provided on the vehicle width right side of the damper chamber 72, and an adjuster portion 74 provided on the vehicle width right side of the damper chamber 72 to adjust the damping action. The main body includes a damper main body 75 including a piston 77 slidably provided in a damper chamber 72 of the damper main body 75, and a rod 71 extending from the piston 77. The front wheel (FIG. 2, FIG. The rotational fluctuation of the steering system 13 received by the reference numeral 17) is attenuated.

  The piston 77 is a member that moves in the damper chamber 72 and partitions the damper chamber 72 into a first chamber 78a and a second chamber 78b. A plurality of orifices 76 communicating with the piston 77 between the first chamber 78a and the second chamber 78b are opened. Further, a first passage 79 a and a second passage 79 b are formed from the first chamber 78 a and the second chamber 78 b to the adjuster portion 74, respectively, and a third passage 80 is formed between the second chamber 78 b and the sub tank 73. ing. The damper chamber 72, the sub tank 73, and the first to third passages 79a, 79b, 80 are all filled with oil.

  The steering damper 25 is disposed below the main frame 26 such that the longitudinal axis X of the steering damper 25 extends in the longitudinal direction of the vehicle, and at least the damper main body 75 of the steering damper 25 is the main frame 26 in a plan view of the vehicle. It is arranged at the position that overlaps.

  When the front wheel (FIG. 2, reference numeral 17) is in the left-right neutral position, the bottom bridge side connecting portion 100 overlaps the main frame 26. Since the bottom bridge side connecting portion 100 overlaps the main frame 26 at the neutral position, the amount of protrusion in the vehicle width direction during left turning and the amount of protrusion in the vehicle width direction during right turning can be made substantially the same. Since it does not protrude greatly only to the left or right, the amount of protrusion can be leveled, and as a result, the amount of protrusion of the steering damper 25 to the side of the main frame 26 in the vehicle width direction can be kept small.

6-7 demonstrates the bottom bridge side connection part (dumper stay) etc. extended from the bottom bridge to the vehicle rear.
As shown in FIG. 6, the bottom bridge 19 has left and right support holes 111L and 111R for supporting the upper end of the front fork (FIG. 4, reference numeral 18), and moves upward from the bottom bridge central portion 112, that is, in front of the figure. A steering stem 16 as a shaft member is extended toward the side. Reference numerals 113L and 113R denote ribs of the left and right steering stoppers that are in contact with members on the body frame side and restrict the steering angle of the steering system.

  As shown in FIG. 7, the bottom bridge 19 has a stem hole 114 into which the lower portion of the steering stem 16 is inserted at the center in the vehicle width direction, and a left side in the vehicle width direction from the bottom bridge central portion 112 where the stem hole 114 is opened. The left arm 115L is extended, and the right arm 115R is extended from the bottom bridge central portion 112 to the right in the vehicle width direction.

  Referring also to FIG. 6, a plate-like bottom bridge side connecting portion 100 extends from the rear portion 19 c of the bottom bridge central portion 112 toward the rear of the vehicle. The bottom bridge side connecting portion 100 is a tapered member whose cross-sectional area becomes smaller toward the tip end 100a with respect to the base portion 101. The bottom bridge side connecting portion 100 includes an upper plate portion 121 and left and right side plate portions 122L and 122R extending downward from left and right ends in the vehicle width direction of the upper plate portion 121, and having a U-shaped cross section opened downward. A cylindrical member 104 as a fastening portion to which the rod (FIG. 5, reference numeral 71) of the steering damper 25 is connected is fixed to the tip 100a.

  The bottom bridge side connecting portion 100 is a tapered member whose cross-sectional area becomes smaller toward the tip end 100a with respect to the base portion 101. That is, the cross-sectional area of the base where the highest stress is generated is increased, and the cross-sectional area is sequentially decreased from the base 101 to reduce the cross-sectional area of the tip 100a. Since the cross-sectional area of the member is changed according to the strength condition, the bottom bridge side connecting portion 100 can be reduced in size.

Next, the structure of the swing arm support will be described.
As shown in FIG. 8, a pivot shaft 125 is passed to the pivot plate 27, and a front end 58a of the swing arm is rotatably supported by the pivot shaft 125.
A cylindrical member 131 is provided on the vehicle width left side of the front end 58a of the swing arm, and the pivot shaft 125 is passed through the cylindrical member 131. Specifically, the left support collar 132 is inserted into the pivot shaft 125, and the needle bearing 133 is inserted into the outer periphery 132a of the left support collar. A cylindrical member 131 is rotatably supported on the outer periphery 133a of the needle bearing.

  A stepped cylindrical member 141 is provided on the vehicle width right side of the front end 58a of the swing arm, and the pivot shaft 125 is passed through the stepped cylindrical member 141. Specifically, a right support collar 142 having a stepped portion 144 is inserted into the pivot shaft 125 from the outside in the vehicle width direction, and the radial bearing 143 comes from the outside in the vehicle width direction so as to contact the outer side surface 142b of the right support collar. The stepped cylindrical member 141 is rotatably supported on the outer periphery of the radial bearing 143. The pivot plate 27 is fastened from the outer side of the radial bearing 143 through the collar circlip 145.

Thus, the right support collar 142 having the stepped portion 144 has the stepped portion 144 having a large outer diameter on the outer side of the vehicle width, and the stepped portion 144 is inserted from the outer side of the vehicle width to be a cylindrical member. 141 so as to be in contact with the stepped portion 146.
If the support collar is inserted from the inside of the vehicle width, the right support collar 142 is easily detached from the stepped cylindrical member 141 when the swing arm 58 is removed.

In this regard, according to the structure of the present invention, there is no fear that the support collar 142 is detached when the swing arm 58 is removed, and the workability related to the attachment / detachment of the swing arm 58 can be improved.
A spacer 147 is provided between the cylindrical member 131 and the stepped cylindrical member 131. 150 is a cross member.

The operation of the motorcycle described above will be described next.
FIG. 9A shows a state in which the steering system 13 is steered to the left, and the rod 71 extends from the damper main body 75.
FIG. 9B shows a state in which the steering system 13 is in the left-right neutral state, and most of the rod 71 is accommodated in the damper main body 75.
FIG. 9C shows a state where the steering system 13 is turned to the right, and the rod 71 extends from the damper main body 75.

  When the front wheel (FIG. 1, reference numeral 17) is in the left-right neutral position, the bottom bridge side connecting portion 100 overlaps the main frame 26. Since the bottom bridge side connecting portion 100 overlaps the main frame 26 at the neutral position, the amount of protrusion in the vehicle width direction during left turning and the amount of protrusion in the vehicle width direction during right turning can be made substantially the same. Since it does not protrude greatly only to the left or right, the amount of protrusion can be leveled, and as a result, the amount of protrusion of the steering damper 25 to the side of the main frame 26 in the vehicle width direction can be kept small.

  The steering damper 25 is disposed below the main frame 26 such that its longitudinal axis X extends in the longitudinal direction of the vehicle, and at least a part of the steering damper 25 is disposed at a position where it overlaps the mono-backbone main frame 26. The

  Compared to the case where the steering damper 25 does not overlap the main frame 26, if the steering damper 25 is disposed at a position where the steering damper 25 overlaps the main frame 26, the steering damper 25 can be disposed compactly.

Returning to FIG. 2, the steering damper 25 is arranged behind the head pipe 12 in the vehicle.
If the steering damper 25 is disposed in front of the vehicle from the head pipe 12, it is necessary to avoid interference with various members such as the cowl stay 31 and the front cowl 21 and the headlight 65 supported by the cowl stay 31.

  In this regard, in the present invention, since the steering damper 25 is not disposed outward in the vehicle width direction nor in front of the head pipe 12, the bridge member including the bottom bridge 19 and the arrangement of the parts of the head pipe 12 in the front of the vehicle. Increased freedom.

  In addition, an intake system 50 that supplies outside air to the engine 36 is provided above the engine 36 and below the steering damper 25. The steering damper 25 and the intake system 50 are arranged below the main frame 26 above the engine 36 with large space constraints. As a result, the vehicle as a whole can be made compact.

  Returning to FIG. 3, the steering damper 25 is disposed in a region surrounded by a main frame and a line connecting the lowest point 81 of the bent portion 26 c and the lower end of the steering stem. The steering damper 25 can be efficiently arranged using an area that tends to be a dead space below the main frame 26.

Although the present invention is applied to a motorcycle in the embodiment, it can also be applied to a tricycle and can be applied to a general saddle type vehicle.
In claim 1, the front fork may be supported by the bottom bridge and the top bridge.
In claim 2, the main frame may be a circular tube or a member obtained by processing the circular tube.

  The present invention is suitable for a motorcycle equipped with a steering damper.

  DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 11 ... Body frame, 12 ... Head pipe, 13 ... Steering system, 17 ... Front wheel, 18 ... Front fork, 19 ... Bottom bridge, 19b ... Bottom end of bottom bridge, 25 ... Steering damper, 26 ... Main frame , 26c ... bent portion, 36 ... engine, 50 ... intake system, 55 ... cylinder shaft, 71 ... rod, 72 ... damper chamber, 81 ... bent portion, 82L, 82R ... left and right side surfaces, 83 ... upper surface, 84 ... Lower surface, 90 ... frame side connecting part, 100 ... bottom bridge side connecting part, 101 ... base.

Claims (8)

The vehicle body frame (11) is provided with a head pipe (12) and a main frame (26) extending from the head pipe (12) to the rear of the vehicle. A steering stem (16) is rotatable on the head pipe (12). The bottom of the steering stem (16) is provided with a bottom bridge (19), and the bottom bridge (19) supports a front fork (18) that rotatably supports a front wheel (17). Steering that attenuates the rotational fluctuation of the steering system (13) received by the front wheels (17) by the expansion and contraction of the rod (71) extending from the damper chamber (72) between the bridge (19) and the vehicle body frame (11). In a motorcycle in which a damper (25) is interposed,
The main frame (26) is a mono backbone frame,
The steering damper (25) is disposed below the main frame (26) such that the longitudinal axis of the steering damper (25) extends in the longitudinal direction of the vehicle, and at least the steering damper ( 25) A motorcycle characterized in that a part of 25) is arranged at a position overlapping the main frame (26).   The motorcycle according to claim 1, wherein the front fork (18) is supported only by the bottom bridge (19). The main frame (26) includes left and right side surfaces (82L, 82R), an upper surface (83) extending to the upper ends of the left and right side surfaces (82L, 82R), and lower ends of the left and right side surfaces (82L, 82R). A rectangular frame with a rectangular cross section consisting of a lower surface (84) passed to
A frame side connecting portion (90) for connecting the main frame (26) and the steering damper (25) is provided on one side surface (82L, 82R) of the left and right side surfaces (82L, 82R). The motorcycle according to claim 1 or 2, characterized in that   A bottom bridge side connecting portion (100) connected to the bottom bridge (19) and the steering damper (25) extends rearward from the rear portion of the bottom bridge (19), and the bottom bridge side connecting portion (100). The motorcycle according to claim 3, wherein the motorcycle is disposed at a position overlapping the main frame (26) when the front wheel (17) is in a left-right neutral position in a plan view of the vehicle.   The motorcycle according to claim 4, wherein the bottom bridge side connecting portion (100) is a tapered member having a cross-sectional area that decreases toward the tip with respect to the base portion (101). The body frame (11) is provided with an engine (36) as a drive source in which a cylinder shaft (55) extends horizontally,
An intake system (50) for supplying outside air to the engine (36) is provided above the engine (36) and below the steering damper (25). The motorcycle according to any one of the above.   The main frame (26) is bent through a bent portion (26c) and has a V-shape opening upward in a side view of the vehicle. The lowermost point (81) of the bent portion and the bottom The steering damper (25) is arranged in a space below the main frame (26) above the line (L) connecting the lower ends (19b) of the bridge. The motorcycle according to item 1.   The side cover (23a) covering a side of the main frame (26) extends downward, and the side cover (23a) covers the side of the steering damper (25). The motorcycle according to any one of claims 7 to 9.

Images