TWI572511B - Saddle-riding vehicle - Google Patents

Description

Straddle type vehicle

The present invention relates to a straddle type vehicle.

There is a locomotive in which a fuel tank is disposed under a flat foot board for reasons such as an increase in the capacity of the storage box (for example, refer to Japanese Patent Laid-Open No. 2007-8316).

On the other hand, in the straddle type vehicle, in order to use the catalyst for treating the exhaust gas to be activated in advance, there is a strong demand for the catalyst to be disposed further upstream of the exhaust pipe. For example, in Japanese Patent Laid-Open No. 2013-36422, there is disclosed a locomotive having a catalyst that is disposed more upstream than a silencer.

Further, the locomotive of Japanese Patent Laid-Open No. 2007-8316 and Japanese Patent Laid-Open No. 2013-36422 includes an engine unit having: an engine; an exhaust pipe connected to the engine; and a muffler connected to the exhaust tube. The engine unit is a so-called unit swing type engine unit that is rockably supported by the body frame. The engine unit is disposed below the seat. A flat foot pedal for the rider's foot is placed below and in front of the seat. The flat foot pedal is placed in front of the engine unit. Since the engine unit is slidably supported by the vehicle body frame below the seat portion, the space of the flat foot pedal that is disposed further forward and lower than the seat portion can be ensured.

The catalyst is at a higher temperature than the exhaust pipe. Further, in a straddle type vehicle in which at least a part of the engine is disposed below the seat portion, the more the catalyst is disposed upstream, the closer the catalyst is to the rider's foot, and the heat of the catalyst must be taken into consideration. The influence of the feet of the person.

Further, in a straddle type vehicle having a flat foot pedal, the engine is disposed behind the flat foot pedal. Therefore, when the fuel tank is disposed below the flat foot pedal, the more the catalyst is disposed upstream, the closer the catalyst is to the fuel tank. Therefore, the impact of the heat of the catalyst on the fuel tank must also be considered.

Further, from the viewpoint of easiness of getting off the rider, the leg portion of the flat foot pedal is preferably formed to be wide in the vehicle width direction, and is disposed at a lower position. In this case, when the fuel tank is disposed below the flat foot pedal, the fuel tank is formed wider in the vehicle width direction in order to ensure a larger capacity of the fuel tank. Therefore, it is easy to affect the fuel tank when the catalyst is placed upstream.

An object of the present invention is to achieve early activation of a catalyst in a straddle type vehicle having a fuel tank disposed below a flat foot pedal, and to suppress heat from a catalyst to a rider's foot and a fuel tank. influences.

A straddle type vehicle according to an aspect of the present invention includes a vehicle body frame, a seat portion, a flat foot pedal, a fuel tank, a vehicle body casing, an opening portion, and an engine unit. The seat supports the body frame. Furthermore, the seat portion can be directly supported by the vehicle body frame, or can be indirectly supported by the vehicle body frame via other members. The flat foot pedal is disposed further below and further forward than the seat. The fuel tank is disposed below the flat foot pedal. The body shell is disposed on the side of the fuel tank. The opening guides the traveling wind between the fuel tank and the vehicle body casing. The engine unit is disposed behind the flat foot pedal and the fuel tank, and is rotatably supported by the vehicle body frame. At least a portion of the engine unit is located below the seat. The engine unit contains the engine, exhaust pipe, silencer, and catalyst. The engine has an exhaust port. The exhaust pipe is connected to the exhaust port. The silencer is connected to the exhaust pipe. The catalyst is disposed in the exhaust pipe. The exhaust pipe includes a first exhaust pipe, a catalyst storage portion, and The second exhaust pipe. The first exhaust pipe is located upstream of the catalyst and is connected to the exhaust port. The catalyst storage unit is connected to the first exhaust pipe and extends rearward to accommodate the catalyst. The second exhaust pipe is located downstream of the catalyst, is connected to the catalyst containing portion, extends rearward, and is connected to the muffler. At the time of the forward looking vehicle, at least a portion of the first exhaust pipe overlaps the fuel tank. At least a part of the catalyst containing portion is disposed behind the space between the fuel tank and the vehicle body casing.

In the straddle type vehicle of the present aspect, by bringing the catalyst into the exhaust pipe as much as possible upstream, the temperature rise of the catalyst after the engine is started can be accelerated, and the catalyst can be activated in advance. Further, after the catalyst is activated, the vehicle can be driven to cool the catalyst by the traveling wind between the fuel tank and the outer casing of the vehicle body. Therefore, by placing the catalyst in the exhaust pipe as much as possible upstream, even if the catalyst is disposed near the position below the seat portion, the influence of heat on the rider's foot can be reduced. Moreover, even if the catalyst is close to the fuel tank disposed below the flat foot pedal, the influence of heat on the fuel tank can be reduced.

Preferably, the cylinder axis of the engine is disposed in a direction crossing the vertical direction. The rocking center and the catalyst housing of the engine unit are located below the cylinder axis. At least a part of the catalyst containing portion is disposed behind the space between the fuel tank and the vehicle body casing within the entire shaking range of the catalyst containing portion. In this case, the catalyst can always be located where the driving wind is often blown.

Preferably, the seat portion is for the rider to ride the front seat portion. The catalyst containing portion overlaps the front seat portion in the front-rear direction of the vehicle. At least a portion of the catalyst containing portion is exposed when the vehicle is viewed from the side. In the forward view vehicle, the inner portion of the catalyst containing portion overlaps with the fuel tank.

In this case, the catalyst containing portion can be disposed closer to the center side of the vehicle than when the fuel tank is disposed outside the fuel tank in the vehicle width direction. Thereby, the thermal influence of the rider's foot on the ground at the time of parking can be suppressed. On the other hand, since at least a part of the catalyst containing portion is exposed when the vehicle is viewed from the side, the outer side portion of the catalyst can be more effectively cooled. Further, although it is difficult for the traveling wind to reach the inner portion of the catalyst containing portion that overlaps the fuel tank, since the catalyst containing portion is sufficiently cooled, the heat influence on the fuel tank is suppressed. system.

Preferably, the fuel tank includes an inclined portion. The inclined portion is inclined upward and outward when it is attached to the front view vehicle. At the time of the forward-looking vehicle, at least a portion of the inclined portion overlaps with the catalyst containing portion. In this case, by guiding the traveling wind to the catalyst containing portion by the inclined portion, the cooling performance of the catalyst can be improved.

Preferably, at least a part of the inclined portion overlaps the first exhaust pipe in the forward view vehicle. In this case, by guiding the traveling wind to the first exhaust pipe by the inclined portion, the cooling performance of the catalyst can be further improved.

Preferably, the engine unit further comprises a cooling fan unit. At least a portion of the catalyst containing portion is located further forward than the center of rotation of the cooling fan device. In this case, the catalyst can be cooled by the air flow generated by the cooling fan unit. Thereby, the cooling performance of the catalyst can be further improved.

Preferably, the engine unit further comprises a cooling fan unit. The cooling fan device and the catalyst containing portion are disposed on the same side with respect to the center line of the vehicle extending in the vehicle front-rear direction. In this case, the catalyst can be cooled by the air flow generated by the cooling fan unit. Thereby, the cooling performance of the catalyst can be further improved.

Preferably, the body shell extends to a position further rearward than the fuel tank. When the vehicle is viewed from the side, at least a portion of the catalyst containing portion does not overlap with the vehicle body casing. In this case, by at least a part of the catalyst containing portion being exposed, the cooling performance of the catalyst can be further improved.

Preferably, the straddle type vehicle further includes a link mechanism. The linkage mechanism connects the engine unit to the body frame. At least a portion of the catalyst containing portion is located on a side of the link mechanism. In this case, the catalyst accommodating portion can be disposed as far as possible upstream as compared with the case where it is disposed below the link mechanism, and the minimum ground clearance can be ensured to be large.

Preferably, the straddle type vehicle further includes a link mechanism. The linkage mechanism connects the engine unit to the body frame. At least a portion of the catalyst containment portion is located at the link machine when looking up the vehicle After the construction. In this case, the catalyst containing portion can be disposed as far as possible upstream as compared with the case where it is disposed below the link mechanism, and the minimum ground clearance can be ensured to be large.

Preferably, the straddle type vehicle further includes a protective member. The protective member is disposed below the catalyst containing portion. In this case, the catalyst containing portion can be protected from obstacles such as stones by the protective member.

Preferably, the straddle type vehicle further includes a link mechanism. The linkage mechanism connects the engine unit to the body frame. The protective member is attached to the link mechanism. In this case, the protective member can be easily disposed below the catalyst containing portion.

Preferably, the protective member is mounted to the engine. In this case, the protective member can be easily disposed below the catalyst containing portion.

Preferably, an air guiding path, a first opening, and a second opening are provided between the protective member and the catalyst containing portion. The first opening communicates with the external space before the air guiding path. The second opening communicates with the external space behind the air guiding path. In this case, the catalyst can be cooled by the traveling wind passing through the air guiding path from the first opening and departing from the second opening. Thereby, the cooling performance of the catalyst can be further improved.

Preferably, the engine includes ribs. The rib extends from the engine to a position below the catalyst containing portion. In this case, the catalyst accommodation portion can be protected from obstacles such as stones by the ribs.

Preferably, the engine unit further includes a cooling fan device and a heat insulating member for the engine. The cooling fan unit is disposed on the side of the engine. The engine heat insulating member is disposed between the cooling fan device and the catalyst containing portion. In this case, it is possible to suppress the heat of the catalyst from being directly transmitted to the cooling air of the cooling fan unit. Moreover, by guiding the traveling wind by the heat insulating member for the engine, the cooling property of the catalyst can be improved.

Preferably, the engine unit further includes a heat insulating member for the engine. The engine heat insulating member is disposed between the engine and the catalyst containing portion. In this case, the heat of the catalyst can be suppressed from being directly transmitted to the engine.

Preferably, an air guiding path, a first opening, and a second opening are provided between the heat insulating member for the engine and the catalyst containing portion. The first opening communicates with the external space before the air guiding path. 2 Opening behind the air guiding path and communicating with the external space. In this case, the heat of the catalyst can be inhibited from being directly transmitted to the engine by the heat insulating member of the engine. Moreover, the catalyst can be cooled by the traveling wind passing through the air guiding path from the first opening and departing from the second opening. Thereby, the cooling performance of the catalyst can be further improved.

Preferably, the straddle type vehicle further includes a heat insulating member for a fuel tank. The fuel tank heat insulating member is disposed between the fuel tank and the catalyst containing portion. In this case, the heat of the catalyst can be inhibited from being directly transmitted to the fuel tank.

Preferably, the straddle type vehicle further includes a wind guide member. The wind guide member is disposed between the fuel tank and the catalyst containing portion, and guides the traveling wind from the lower side of the fuel tank toward the catalyst containing portion. In this case, the catalyst can be cooled by guiding the traveling wind flowing under the fuel tank toward the catalyst containing portion by the air guiding member. Thereby, the cooling performance of the catalyst can be further improved.

Preferably, at least a portion of the catalyst containing portion is located below the bottom surface of the fuel tank in a state where the engine unit is located at the lowest position in the rocking range. In this case, at least a part of the catalyst containing portion is located below the bottom surface of the fuel tank, so that the traveling wind easily reaches the catalyst containing portion. Thereby, the cooling ability of the catalyst can be further improved.

Preferably, the body frame includes a lower frame. The bottom frame extends below the flat foot pedal and toward the rear. In the case of a forward looking vehicle, at least a portion of the catalyst containment portion is located below the bottom frame. In this case, the cooling ability of the catalyst can be further improved by guiding the traveling wind to the catalyst containing portion by the bottom frame.

In the straddle type vehicle of the present aspect, by bringing the catalyst into the exhaust pipe as much as possible upstream, the temperature rise of the catalyst after the engine is started can be accelerated, and the catalyst can be activated in advance. Moreover, after the catalyst is activated, the vehicle can be used to pass through the fuel tank and the vehicle body. The traveling wind between the outer casing cools the catalyst. Therefore, by placing the catalyst in the exhaust pipe as much as possible upstream, even if the catalyst is disposed near the position below the seat portion, the influence of heat on the rider's foot can be reduced. Further, by placing the catalyst in the exhaust pipe as much as possible upstream, even if the catalyst is close to the fuel tank disposed below the flat foot pedal, the influence of heat on the fuel tank can be reduced.

1‧‧‧Sitting vehicle

2‧‧‧ body frame

3‧‧‧ Front fork

4‧‧‧ front wheel

5‧‧‧

5a‧‧‧Front seat

5b‧‧‧back seat

6‧‧‧ body shell

7‧‧‧fuel tank

8‧‧‧ engine unit

9‧‧‧ Rear wheel

10‧‧‧Hands

11‧‧‧ head tube

12‧‧‧ Lower frame

13‧‧‧1st bottom frame

14‧‧‧2nd bottom frame

15‧‧‧1st back frame

16‧‧‧2nd rear frame

17‧‧‧1st link frame

18‧‧‧2nd Linked Framework

21‧‧‧ front casing

22‧‧‧ bottom shell

23‧‧‧ rear casing

23a‧‧‧The front part of the rear casing

23b‧‧‧Side side of the rear casing

24‧‧‧ flat foot pedals

25‧‧‧1st bottom bottom shell

26‧‧‧2nd bottom bottom shell

27‧‧‧ Housing Department

29‧‧‧Intermediate bottom casing

31‧‧‧ Engine

32‧‧‧Transmission

33‧‧‧Cooling fan unit

34‧‧‧Exhaust pipe

35‧‧‧Muffler

36‧‧‧ catalyst

37‧‧‧ linkage mechanism

37a‧‧‧1st link

37b‧‧‧2nd link

41‧‧‧1st exhaust pipe

42‧‧‧ Catalyst Containment Department

43‧‧‧2nd exhaust pipe

45‧‧‧Fan casing

46‧‧‧Cooling fan

51‧‧‧Protection components

52‧‧‧ Wind path

53‧‧‧1st opening

54‧‧‧2nd opening

55‧‧‧ Ribs

56‧‧‧Insulation members for engines

57‧‧‧Insulation members for fuel tanks

58‧‧‧air guiding members

61‧‧‧1st opening

62‧‧‧2nd opening

63‧‧‧3rd opening

64‧‧‧4th opening

65‧‧‧5th opening

71‧‧‧ box body

72‧‧‧1st outer casing installation

73‧‧‧2nd outer casing installation

74‧‧‧1st inclined part

75‧‧‧2nd inclined part

76‧‧‧ oil supply port

77‧‧‧1st box installation

78‧‧‧Second box installation department

79‧‧‧ box enclosure

100‧‧‧Sitting vehicle

251‧‧‧ recess

281‧‧‧ openings

282‧‧‧ openings

311‧‧‧ crankcase

312‧‧ ‧ cylinder

313‧‧‧ crankshaft

314‧‧‧Exhaust gas

315‧‧‧ intake 埠

451‧‧‧Mesh Department

452‧‧‧Exhaust pipe outer casing

A1‧‧‧ arrow

A2‧‧‧ arrow

AX1‧‧‧Cylinder axis

C1‧‧‧Shake Center

C2‧‧‧ Rotation Center

C3‧‧‧ center line

Figure 1 is a right side view of a straddle type vehicle.

2 is a right side view showing a body frame and an engine unit of a straddle type vehicle.

Figure 3 is a bottom plan view showing the body frame and the engine unit.

Figure 4 is a front view showing the body frame and the engine unit.

Figure 5 is a right side view showing a portion of a straddle type vehicle.

Figure 6 is a bottom plan view showing a portion of a straddle type vehicle.

Figure 7 is a cross-sectional view taken along line VII-VII of Figure 6.

Figure 8 is a cross-sectional view of the engine unit.

Fig. 9 is a view showing a state in which the engine unit is located at the lowest position in the rocking range.

Fig. 10 is a view showing a state in which the engine unit is located at the uppermost position in the shaking range.

Figure 11 is a front elevational view showing a portion of the body frame and the engine unit.

12A and 12B are views showing a part of a straddle type vehicle according to a first modification.

13A and 13B are views showing a part of a straddle type vehicle according to a second modification.

Fig. 14 is a cross-sectional view showing a protective member and a catalyst containing portion of still another example of the first modification or the second modification.

15A and 15B are views showing a part of a straddle type vehicle of a fourth modification.

16A and 16B are views showing a part of a straddle type vehicle of a fifth modification.

Fig. 17 is a bottom plan view showing a part of a straddle type vehicle of a sixth modification.

18A and 18B are views showing a part of a straddle type vehicle of a seventh modification.

19A and 19B are views showing a part of a straddle type vehicle of an eighth modification.

20A and 20B are views showing a part of a straddle type vehicle of a ninth modification.

Fig. 21 is a view showing a part of a straddle type vehicle of a tenth modification.

Fig. 22 is a bottom plan view showing a part of the straddle type vehicle of the eleventh modification.

Fig. 23 is a side view of the straddle type vehicle of the eleventh modification.

Hereinafter, a straddle type vehicle of an embodiment will be described with reference to the drawings. Fig. 1 is a right side view of the straddle type vehicle 1 of the embodiment. The straddle type vehicle 1 is a speed locomotive. The straddle type vehicle 1 includes a body frame 2, a front fork 3, a front wheel 4, a seat portion 5, a vehicle body casing 6, a fuel tank 7, an engine unit 8, and a rear wheel 9. Further, in the present embodiment, the directions of the front, rear, left, and right directions refer to the direction when the rider riding on the seat portion 5 views.

The body frame 2 includes a head pipe 11 and a lower frame 12. The head pipe 11 rotatably supports the front fork 3. A handle 10 is mounted on the upper portion of the front fork 3. The lower portion of the front fork 3 rotatably supports the front wheel 4. The lower frame 12 extends downward from the head pipe 11.

2 is a right side view showing the vehicle body frame 2 and the engine unit 8. 3 is a bottom view showing the vehicle body frame 2 and the engine unit 8. 4 is a front view showing the body frame 2 and the engine unit 8. As shown in FIGS. 1 to 4 , the vehicle body frame 2 includes a first bottom frame 13 , a second bottom frame 14 , a first rear frame 15 , and a second rear frame 16 .

The first bottom frame 13 and the second bottom frame 14 are connected to the lower portion of the lower frame 12, and extend rearward from the lower portion of the lower frame 12. Specifically, the first bottom frame 13 is inclined obliquely upward toward the rear. The second bottom frame 14 is inclined obliquely downward toward the rear. The first bottom frame 13 and the second bottom frame 14 are spaced apart from each other in the vehicle width direction. In the present embodiment, the first bottom frame 13 is a right bottom frame, and the second bottom frame 14 is a left bottom frame. The connection portion between the first bottom frame 13 and the lower frame 12 is located below the connection portion between the second bottom frame 14 and the lower frame 12.

The first rear frame 15 is connected to the rear portion of the first bottom frame 13, and extends obliquely rearward and upward from the rear portion of the first bottom frame 13. The second rear frame 16 is connected to the rear portion of the second bottom frame 14 from The rear portion of the second bottom frame 14 extends obliquely rearward and upward. In the present embodiment, the first rear frame 15 is a right rear frame, and the second rear frame 16 is a left rear frame.

Further, part or all of the head pipe 11, the lower frame 12, the bottom frames 13, 14 and the rear frames 15, 16 may be an integral member. Alternatively, part or all of the head pipe 11, the lower frame 12, the bottom frames 13, 14, and the rear frames 15, 16 may be individual members and joined to each other by a fixing method such as welding.

As shown in FIG. 3, the vehicle body frame 2 includes a first connecting frame 17. The first joint frame 17 extends in the vehicle width direction. The first connecting frame 17 is provided across the first bottom frame 13 and the second bottom frame 14. The first connecting frame 17 connects the first bottom frame 13 and the second bottom frame 14 . As shown in FIGS. 2 and 4 , the vehicle body frame 2 includes a second connecting frame 18 . The second connecting frame 18 is provided across the first rear frame 15 and the second rear frame 16. The first connecting frame 17 connects the first rear frame 15 and the second rear frame 16 .

As shown in FIG. 1, the seat portion 5 is supported by the vehicle body frame 2. Specifically, the accommodating portion 27 is supported by the vehicle body frame 2, and the seat portion 5 is supported by the accommodating portion 27. The seat portion 5 is disposed above the first rear frame 15 and the second rear frame 16. The seat portion 5 includes a front seat portion 5a and a rear seat portion 5b. The front seat portion 5a is a portion for the rider to ride. The rear seat portion 5b is located behind the front seat portion 5a, and the upper surface of the rear seat portion 5b is located above the upper surface of the front seat portion 5a. Further, the front seat portion 5a and the rear seat portion 5b do not have to be clearly separated, and the upper surface of the rear seat portion 5b may be flush with the upper surface of the front seat portion 5a. In this case, the front seat portion may be the first half of the full length of the seat portion 5. Alternatively, when a step difference is given to the seat portion 5, the front seat portion may be a portion having a higher step.

The body casing 6 is supported by the body frame 2. The vehicle body casing 6 includes a front outer casing 21, a bottom outer casing 22, and a rear outer casing 23. The front outer casing 21 covers the circumference of the head pipe 11 and the lower frame 12. The bottom case 22 covers the periphery of the first bottom frame 13 and the second bottom frame 14.

In detail, the bottom housing 22 includes a flat foot pedal 24. The flat footboard 24 is the upper surface of the bottom outer casing 22. The flat footboard 24 is disposed further below and further forward than the seat portion 5. The flat footboard 24 is disposed above the first bottom frame 13 and the second bottom frame 14. The first bottom frame 13 and the second bottom frame 14 extend below the flat footboard 24 and extend rearward. The flat footboard 24 has a flat shape.

In addition, the "flat foot pedal 24 is flat" means that the flat footboard 24 is flat in the vehicle width direction, and there is no center for the vehicle body frame 2 in the vehicle width direction of the flat footboard 24. a part of the space of the convex part. Alternatively, the term "flat foot pedal 24 flat" means flat to the extent that the rider can place the foot on any part of the flat footboard 24. Therefore, it is also possible to form, for example, unevenness for slipping or the like on the flat footboard 24.

FIG. 5 is a right side view showing a portion of the straddle type vehicle 1. Fig. 6 is a bottom view showing a part of the straddle type vehicle 1. As shown in FIGS. 5 and 6, the bottom casing 22 includes a first side bottom casing 25, a second side bottom casing 26, and an intermediate bottom casing 29. The first side bottom outer casing 25 is disposed on one side of the fuel tank 7, and the second side bottom outer casing 26 is disposed on the other side of the fuel tank 7. In the present embodiment, the first side bottom outer casing 25 is disposed on the right side of the fuel tank 7, and the second side bottom outer casing 26 is disposed on the left side of the fuel tank 7. The intermediate bottom casing 29 is disposed between the first side bottom casing 25 and the second side bottom casing 26. Further, in Fig. 6, for the sake of easy understanding, only the outer bottom case 29 is formed in a dashed line.

The first side bottom outer casing 25 covers the first bottom frame 13 from the side. The first side bottom outer casing 25 is disposed to the right of the first bottom frame 13. The first side bottom outer casing 25 extends to a position further rearward than the fuel tank 7. Further, it is sufficient that one of the first side bottom outer casings 25 is located on the side of the fuel tank 7. The second side bottom outer casing 26 covers the side of the second bottom frame 14. The second side bottom case 26 is disposed to the left of the second bottom frame 14.

As shown in FIG. 1, the rear outer casing 23 is disposed below the seat portion 5 and surrounds the space below the seat portion 5. The front portion 23a of the rear outer casing 23 extends upward from the rear end of the flat footboard 24. The side portion 23b of the rear outer casing 23 covers the space below the seat portion 5 from the side. Further, a housing portion 27 is disposed below the seat portion 5. The accommodating portion 27 is located above the engine unit 8.

The fuel tank 7 is disposed below the flat footboard 24. As shown in Figure 2 to Figure 4, the fuel tank 7 includes a tank body 71 having an internal space for storing fuel, and a tank casing 79. The box body 71 is disposed between the first bottom frame 13 and the second bottom frame 14. The tank body 71 is disposed in front of the first joint frame 17 . The box body 71 overlaps the first bottom frame 13 when the vehicle is viewed from the side. The tank body 71 includes a first tank mounting portion 77 and a second tank mounting portion 78. The tank body 71 is attached to the first bottom frame 13 at the first tank mounting portion 77. The tank body 71 is attached to the second bottom frame 14 at the second tank mounting portion 78.

The case outer casing 79 is disposed below the case body 71. The case casing 79 includes a first case attaching portion 72 and a second case attaching portion 73. The first outer casing attaching portion 72 has a flange shape. The first outer casing attaching portion 72 is attached to the first bottom frame 13 , the second bottom frame 14 , and the first connecting frame 17 . The front end of the second outer casing mounting portion 73 is attached to the lower end portion of the lower frame 12.

The intermediate bottom casing 29 is not disposed below the tank casing 79. That is, the intermediate bottom casing 29 is disposed further forward than the tank casing 79. The bottom surface of the tank casing 79 is located further below the intermediate bottom casing 29. That is, the bottom surface of the fuel tank 7 is located further below the intermediate bottom casing 29.

The tank casing 79 includes a first inclined portion 74 and a second inclined portion 75. The first inclined portion 74 and the second inclined portion 75 are inclined upward and outward in the forward view vehicle. Specifically, the first inclined portion 74 is a right side portion of the bottom surface of the case outer casing 79. The first inclined portion 74 is inclined upward and to the right. The second inclined portion 75 is a left side portion of the bottom surface of the case outer casing 79. The second inclined portion 75 is inclined upward and leftward. The first inclined portion 74 and the second inclined portion 75 are located below the first outer casing attaching portion 72. The first inclined portion 74 is located below the first bottom frame 13 . The second inclined portion 75 is located below the second bottom frame 14.

As shown in FIG. 4, an oil supply port 76 is attached to the tank body 71, and the fuel supply port 76 is provided with a fuel pipe for supplying fuel to the tank body 71. The fuel supply port 76 protrudes from the tank body 71. In the case of a forward looking vehicle, the fuel supply port 76 is located below the second bottom frame 14. In the case of the forward-looking vehicle, the fuel supply port 76 is located at approximately the same height as the connection portion between the first bottom frame 13 and the lower frame 12.

As shown in FIG. 6, the bottom casing 22 is not disposed below at least a portion of the fuel tank 7. Therefore, a gap is provided between the fuel tank 7 and the bottom casing 22. Figure 7 is the figure in Figure 6. Section VII-VII. As shown in FIG. 7, a gap 61 (hereinafter referred to as "first opening 61") is provided between the fuel tank 7 and the first side bottom casing 25. Further, a gap 62 (hereinafter referred to as "second opening portion 62") is provided between the fuel tank 7 and the second side bottom casing 26. The first opening portion 61 and the second opening portion 62 guide the traveling wind between the fuel tank 7 and the vehicle body casing 6 .

Further, the tank casing 79 includes a third opening portion 63. The third opening portion 63 is provided at a central portion of the case outer casing 79 in the vehicle width direction. Further, the tank casing 79 includes a fourth opening portion 64 and a fifth opening portion 65. The fourth opening portion 64 is provided in the first inclined portion 74. The fifth opening 65 is provided in the second inclined portion 75. The third to fifth opening portions 63-65 guide the traveling wind into the space between the box body 71 and the tank case 79. The traveling wind is introduced between the fuel tank 7 and the vehicle body casing 6 through the space between the tank body 71 and the tank casing 79.

By introducing the traveling wind from the first to fifth opening portions 61-65 as described above, the traveling wind is introduced between the fuel tank 7 and the first side bottom casing 25 as shown in FIG. 3 (refer to FIG. Point arrow A1). Further, the traveling wind is introduced between the fuel tank 7 and the second side bottom casing 26 (see an arrow A2 of the two-dot chain line in Fig. 3).

As shown in FIG. 1, the engine unit 8 is disposed behind the flat footboard 24 and the fuel tank 7. The engine unit 8 is a so-called unit swing type unit that is rockably supported by the vehicle body frame 2. The engine unit 8 is located below the seat 5. The engine unit 8 rotatably supports the rear wheel 9. The engine unit 8 includes an engine 31, a transmission 32, a cooling fan unit 33, an exhaust pipe 34, a muffler 35, and a catalyst 36.

The engine 31 is an air-cooled engine. The engine 31 is disposed below the seat portion 5. Figure 10 is a cross-sectional view of the engine unit 8. The engine 31 includes a crankcase 311 and a cylinder 312. The crankcase 311 houses a crankshaft 313. The rotation axis of the crankshaft 313 extends in the vehicle width direction. As shown in FIG. 2, the cylinder 312 is disposed in front of the crankcase 311. The cylinder 312 is disposed between the first rear frame 15 and the second rear frame 16, and one of the cylinders 312 protrudes further forward than the first rear frame 15 and the second rear frame 16. The cylinder axis Ax1, which is the central axis of the cylinder 312, is disposed in a direction crossing the vertical direction. In detail, the cylinder axis Ax1 of the cylinder 312 is inclined obliquely upward toward the front.

As shown in FIG. 2, the engine unit 8 is connected to the vehicle body frame 2 via a link mechanism 37. The engine unit 8 is arranged to be rockable about a rocking center C1 which is located at a connection portion of the link mechanism 37 and the vehicle body frame 2. The rocking center C1 is located below the cylinder axis Ax1.

The transmission case 32 is disposed on one side of the crankcase 311. The cooling fan unit 33 is disposed on the other side of the crankcase 311. In the present embodiment, the transmission case 32 is disposed to the left of the crankcase 311, and the cooling fan device 33 is disposed to the right of the crankcase 311. The gearbox 32 extends rearward from the side of the crankcase 311 and supports the rear wheel 9.

The cooling fan unit 33 generates an air flow for cooling the engine 31. The cooling fan unit 33 cools the engine 31 by generating an air flow flowing around the engine 31. The cooling fan device 33 is disposed behind the first side bottom case 25. The cooling fan device 33 is disposed behind the first rear frame 15. The cooling fan unit 33 has a fan casing 45 and a cooling fan 46.

The fan casing 45 covers the cooling fan 46 from the side. The cooling fan 46 is disposed to be rotatable about a rotation center C2. The fan casing 45 includes a grill portion 451 and an exhaust pipe outer casing portion 452. The grill portion 451 is disposed at a position opposed to the cooling fan 46. The exhaust pipe outer casing portion 452 covers a portion of the exhaust pipe 34 from the side.

As shown in FIG. 2, the cylinder 312 includes an exhaust port 314 and an intake port 315. The exhaust port 314 is located further below the intake port 315. The exhaust pipe 34 is connected to the exhaust port 314. The muffler 35 is connected to the exhaust pipe 34. The muffler 35 is disposed further rearward than the cylinder 312. The muffler 35 is disposed on the side of the rear wheel 9, and overlaps the rear wheel 9 when the vehicle is viewed from the side. In the present embodiment, the muffler 35 is disposed on the right side of the rear wheel 9. The catalyst 36 is disposed in the exhaust pipe 34.

The exhaust pipe 34 includes a first exhaust pipe 41 , a catalyst storage portion 42 , and a second exhaust pipe 43 . The first exhaust pipe 41 is a portion of the exhaust pipe 34 that is located upstream of the catalyst 36 and is connected to the exhaust port 314. Exhaust manifold 314 is disposed on the side of cylinder 312. The first exhaust pipe 41 protrudes downward from the exhaust port 314 and is bent rearward. The first exhaust pipe 41 is disposed to pass the side of the link mechanism 37.

The catalyst storage unit 42 houses the catalyst 36. The outer diameter of the catalyst containing portion is larger than the outer diameter of the first exhaust pipe 41. The outer diameter of the catalyst containing portion 42 is larger than the outer diameter of the second exhaust pipe 43. The catalyst storage unit 42 is connected to the first exhaust pipe 41 and extends rearward. The catalyst containing portion 42 is located below the cylinder axis Ax1. As shown in FIGS. 4 and 7, one portion of the catalyst containing portion 42 is disposed behind the space between the fuel tank 7 and the first side bottom casing 25. Further, in Fig. 4, a part of the trailing edge of the first side bottom case 25 is indicated by a dashed line. In FIG. 7, the catalyst containing portion 42 and the catalyst 36 of the front end portion of the catalyst 36 are indicated by dashed lines.

The second exhaust pipe 43 is located downstream of the catalyst 36. The second exhaust pipe 43 is connected to the catalyst containing portion 42 and extends rearward from the rear end of the catalyst containing portion 42. The second exhaust pipe 43 is disposed between the catalyst storage portion 42 and the muffler 35 and is connected to the muffler 35.

As shown in FIG. 5, the catalyst accommodation portion 42 does not overlap the first side bottom casing 25 when the vehicle is viewed from the side. Therefore, when the vehicle is viewed from the side, the catalyst containing portion 42 is entirely exposed to the outside. The rear portion of the first side bottom outer casing 25 includes a concave portion 251 that is recessed toward the front. When the vehicle is viewed from the side, the catalyst storage portion 42 is disposed behind the concave portion 251.

One of the catalyst containing portions 42 is located laterally of the link mechanism 37. Therefore, when the vehicle is viewed from the side, one portion of the catalyst containing portion 42 overlaps with the link mechanism 37.

The catalyst containing portion 42 overlaps the front seat portion 5a in the vehicle front-rear direction. That is, when the vehicle is viewed from the side, the catalyst containing portion 42 is located below the front seat portion 5a. The catalyst containing portion 42 is located further rearward than the front end portion of the front seat portion 5a. The catalyst containing portion 42 is located further forward than the rear end portion of the front seat portion 5a. The catalyst containing portion 42 is located on the side of the engine 31. Specifically, the catalyst containing portion 42 is located on the side of the crankcase 311. The catalyst containing portion 42 is located further forward than the rotation center C2 of the cooling fan device 33. The catalyst containing portion 42 is located below the rotation center C2 of the cooling fan device 33.

The cooling fan device 33 and the catalyst containing portion 42 are disposed on the same side with respect to the center line C3 of the vehicle extending in the vehicle front-rear direction. In the present embodiment, the cooling fan device 33 and the catalyst containing portion 42 are disposed to the right of the center line C3 of the vehicle extending in the front-rear direction of the vehicle. square. One of the catalyst containing portions 42 is disposed below the cooling fan device 33. The second exhaust pipe 43 is disposed to pass below the cooling fan unit 33. When the vehicle is looked up, one of the catalyst containing portions 42 overlaps with the first rear frame 15. One of the catalyst containing portions 42 is located further inside the vehicle width direction than the first rear frame 15. One of the catalyst containing portions 42 is located further inside than the first bottom frame 13 in the vehicle width direction.

In the present embodiment, the "inside of the vehicle width direction" means a direction in the vehicle width direction that is close to the center line C3 that extends in the front-rear direction through the center in the vehicle width direction. In addition, the "outer side in the vehicle width direction" means a direction opposite to the inner side in the vehicle width direction in the vehicle width direction. In other words, the term "outer side in the vehicle width direction" means a direction away from the center line C3 extending in the front-rear direction through the center in the vehicle width direction.

As shown in FIG. 4, in the forward looking vehicle, one of the first exhaust pipes 41 overlaps the fuel tank 7. In the forward view vehicle, one of the first inclined portions 74 overlaps the catalyst containing portion 42. In the forward view vehicle, the inner portion of the catalyst containing portion 42 overlaps the fuel tank 7. In the case of the forward looking vehicle, the catalyst containing portion 42 is located below the first bottom frame 13.

Further, the position of the component of the engine unit 8 including the catalyst containing unit 42 may be established in at least a part of the rocking range of the engine unit 8. For example, the position of the component of the engine unit 8 including the catalyst containing portion 42 indicates that the knight is not riding on the straddle-type vehicle 1, the front wheel 4 and the rear wheel 9 are in contact with the horizontal plane, and the straddle-type vehicle 1 is in an upright state. s position.

Fig. 9 is a view showing a state in which the engine unit 8 is located at the lowest position in the rocking range. Fig. 10 is a view showing a state in which the engine unit 8 is located at the uppermost position in the rocking range. Figure 11 is a front elevational view showing a portion of the body frame 2 and the engine unit 8. In FIG. 11, the catalyst containing portion 42 in a state where the engine unit 8 is located at the lowest position in the rocking range is indicated by a solid line, and the two-point chain line indicates that the engine unit 8 is located at the uppermost position in the rocking range. The catalyst housing portion 42.

In any of the states in which the engine unit 8 is located at the lowest position in the rocking range and the state in which the engine unit 8 is located at the uppermost position in the rocking range, the bottom end of the bottom portion of the first side bottom casing 25 is located more Above. Therefore, in any of the states in which the engine unit 8 is located at the lowest position in the rocking range and the state in which the engine unit 8 is located at the uppermost position in the rocking range, one of the catalyst containing portions 42 is disposed in the fuel tank. 7 is behind the space between the first side bottom outer casing 25. That is, one of the catalyst containing portions 42 is disposed behind the space between the fuel tank 7 and the first side bottom casing 25 in the entire shaking range of the catalyst containing portion 42.

As shown in FIGS. 9 and 11, in a state where the engine unit 8 is located at the lowest position in the rocking range, one portion of the catalyst containing portion 42 is located below the bottom surface of the fuel tank 7. As shown in FIG. 11, in a state where the engine unit 8 is located at the lowest position in the swing range, one of the first inclined portions 74 overlaps with the first exhaust pipe 41 in the forward view vehicle. As shown in FIGS. 10 and 11, in a state where the engine unit 8 is located at the uppermost position in the swing range, the entirety of the catalyst containing portion 42 is located above the bottom surface of the fuel tank 7.

In the straddle type vehicle 1 of the present embodiment described above, by bringing the catalyst 36 as far as possible upstream of the exhaust pipe 34, the temperature rise of the catalyst 36 after the engine 31 is started can be increased. Thereby, the catalyst 36 can be activated in advance. Further, after the activation of the catalyst 36, the vehicle 36 can be used to cool the catalyst 36 by the traveling wind between the fuel tank 7 and the first side bottom casing 25. Therefore, by placing the catalyst 36 as far as possible upstream in the exhaust pipe 34, even if the catalyst 36 is disposed directly below the front seat portion 5a, the influence of heat on the rider's foot can be reduced. . Further, even if the catalyst 36 is close to the fuel tank 7 disposed below the flat footboard 24, the influence of heat on the fuel tank 7 can be reduced.

At least a part of the catalyst containing portion 42 is disposed behind the space between the fuel tank 7 and the first side bottom casing 25 in the entire rocking range of the catalyst containing portion 42. Therefore, the catalyst 36 can be always placed at a position where the traveling wind is often blown. Further, at least a part of the catalyst accommodating portion 42 is disposed in at least a part of the oscillating range of the catalyst accommodating portion 42. The space between the magazine 7 and the first side bottom outer casing 25 is sufficient.

In the forward view vehicle, the inner portion of the catalyst containing portion 42 overlaps the fuel tank 7. Therefore, the catalyst containing portion 42 can be disposed closer to the center line C3 of the vehicle than when the fuel tank 7 is disposed outside the fuel tank 7 in the vehicle width direction. Thereby, the thermal influence of the rider's foot on the ground at the time of parking can be suppressed. Further, although it is difficult for the traveling wind to reach the inner portion of the catalyst containing portion 42 that overlaps the fuel tank 7, the catalyst containing portion 42 is sufficiently cooled, so that the heat influence on the fuel tank 7 is suppressed. In particular, since the outer side portion of the catalyst containing portion 42 is sufficiently cooled, the thermal influence on the rider's foot can be suppressed.

At the time of the forward-looking vehicle, one of the first inclined portions 74 of the fuel tank 7 overlaps with the catalyst containing portion 42. Therefore, by guiding the traveling wind to the catalyst containing portion 42 by the first inclined portion 74, the cooling performance of the catalyst 36 can be improved.

In the forward view vehicle, one of the first inclined portions 74 overlaps with the first exhaust pipe 41. Therefore, by guiding the traveling wind to the first exhaust pipe 41 by the first inclined portion 74, the cooling performance of the catalyst 36 can be further improved.

The catalyst containing portion 42 is located further forward than the rotation center C2 of the cooling fan device 33. Therefore, the catalyst 36 can be cooled by the air flow generated by the cooling fan unit 33. Thereby, the cooling performance of the catalyst 36 can be further improved.

The cooling fan device 33 and the catalyst containing portion 42 are disposed on the same side with respect to the center line C3 of the vehicle extending in the vehicle front-rear direction. Therefore, the catalyst 36 can be cooled by the air flow generated by the cooling fan unit 33. Thereby, the cooling performance of the catalyst 36 can be further improved.

The first side bottom outer casing 25 extends to a position further rearward than the fuel tank 7, but the catalyst storage portion 42 does not overlap the first side bottom outer casing 25 when the vehicle is viewed from the side. Therefore, by exposing the catalyst containing portion 42, the cooling performance of the catalyst 36 can be further improved.

One of the catalyst containing portions 42 is located laterally of the link mechanism 37. Therefore, compared with the case where the catalyst accommodating portion 42 is disposed below the link mechanism 37, the catalyst accommodating portion 42 can be disposed as far as possible upstream, and the minimum ground clearance can be ensured to be large.

In a state where the engine unit 8 is located at the lowest position in the swing range, one portion of the catalyst containing portion 42 is located below the bottom surface of the fuel tank 7. Therefore, the traveling wind easily reaches the catalyst containing portion 42. Thereby, the cooling ability of the catalyst 36 can be further improved.

In the case of the forward looking vehicle, one of the catalyst containing portions 42 is located below the first bottom frame 13. Therefore, by guiding the traveling wind to the catalyst containing portion 42 by the first bottom frame 13, the cooling ability of the catalyst 36 can be further improved.

The embodiment of the present invention has been described above, but the present invention is not limited to the embodiment described above, and various modifications can be made without departing from the spirit and scope of the invention.

The straddle-type vehicle is not limited to a locomotive. It also includes an all-terrain vehicle (ALL-TERRAIN VEHICLE) and a snowmobile.

The engine 31 is not limited to the air-cooling type, and may be water-cooled. In this case, the cooling fan unit 33 may be a water-cooling radiator fan instead of the forced air-cooling fan. The cylinder axis Ax1 of the engine 31 can also be configured horizontally. The cooling fan unit 33 can also be omitted.

In the above embodiment, the catalyst accommodating portion 42 is disposed on the right side of the center line C3 of the straddle-type vehicle 1 extending in the longitudinal direction of the vehicle, but may be disposed on the left side from the center line C3. In this case, it is preferable that the cooling fan unit 33 and the muffler 35 are disposed on the left side of the center line C3 similarly to the catalyst containing unit 42. The first side bottom outer casing 25 and the second side bottom outer casing 26 may be arranged opposite to the above-described embodiments. Similarly, the first bottom frame 13 and the second bottom frame 14 may be arranged opposite to the above-described embodiments.

It is not limited to the entirety of the engine unit 8, and only one of the engine units 8 is located below the seat 5. In the case of the forward-looking vehicle, the entire first exhaust pipe 41 may be overlapped with the fuel tank 7 without being limited to one portion of the first exhaust pipe 41. The entire catalyst accommodation portion 42 may be disposed behind the space between the fuel tank 7 and the vehicle body casing 6 without being limited to one portion of the catalyst accommodation portion 42.

In the case of the forward-looking vehicle, the entire first inclined portion 74 may be overlapped with the catalyst containing portion 42 without being limited to one portion of the first inclined portion 74. In the case of a forward-looking vehicle, it is not limited The entire first inclined portion 74 overlaps the first exhaust pipe 41 at a portion of the first inclined portion 74.

It is not limited to the entirety of the catalyst containing portion 42 , and only one portion of the catalyst containing portion 42 is located further forward than the rotation center C2 of the cooling fan device 33 . In other words, the front end portion of the catalyst containing portion 42 may be located further forward than the rotation center C2 of the cooling fan device 33, and the rear end portion of the catalyst containing portion 42 may be located further rearward than the rotation center C2 of the cooling fan device 33.

When the vehicle is viewed from the side, it is not limited to the entirety of the catalyst containing portion 42 , and only one of the catalyst containing portions 42 does not overlap the first side bottom casing 25 . In other words, the entire catalyst storage unit 42 is not limited to the entire one, and only one of the catalyst storage portions 42 is exposed when the vehicle is viewed from the side. It is not limited to one portion of the catalyst containing portion 42 but the entire catalyst containing portion 42 is located on the side of the link mechanism 37.

The entire oscillating range of the catalyst accommodating portion 42 is not limited to one portion of the catalyst accommodating portion 42, but the entire catalyst accommodating portion 42 is disposed behind the space between the fuel tank 7 and the vehicle body casing 6. . In a state in which the engine unit 8 is located at the lowest position in the rocking range, it is not limited to one portion of the catalyst containing portion 42, but the entire catalyst containing portion 42 is located below the bottom surface of the fuel tank 7. In the case of the forward-looking vehicle, the entire catalyst accommodation portion 42 is not limited thereto, and only one of the catalyst accommodation portions 42 is located below the bottom frame. At least a part of the catalyst accommodating portion 42 may be disposed behind the space between the fuel tank 7 and the vehicle body casing 6 only in a part of the oscillating range of the catalyst accommodating portion 42.

The straddle-type vehicle 1 may also be provided with a protective member. For example, FIG. 12A is a side view showing a part of the straddle type vehicle of the first modification. Fig. 12B is a bottom view showing a part of the straddle type vehicle of the first modification. As shown in FIGS. 12A and 12B, the protective member 51 is disposed below the catalyst containing portion 42. The protective member 51 is attached to the link mechanism 37. In this case, the catalyst containing portion 42 can be protected from an obstacle such as a stone by the protective member 51.

The protective member 51 may be attached to a member other than the link mechanism 37. For example, FIG. 13A is a side view showing a part of a straddle type vehicle of a second modification. Figure 13B shows the second change A bottom view of one of the straddle-type vehicles of the example. As shown in FIGS. 13A and 13B, the protective member 51 is attached to the engine 31. In detail, the protective member 51 is attached to the crankcase 311.

An air guiding path may be provided between the protective member 51 and the catalyst containing portion 42. For example, as shown in FIG. 14, the air guiding path 52, the first opening 53, and the second opening 54 are provided between the protective member 51 and the catalyst containing portion 42. The first opening 53 communicates with the external space in front of the air guiding path 52. The second opening 54 communicates with the external space behind the air guiding path 52. Therefore, the catalyst 36 can be cooled by the traveling wind passing through the air guiding path 52 from the first opening 53 and departing from the second opening 54. Thereby, the cooling performance of the catalyst 36 can be further improved.

The engine 31 may also include ribs for protecting the catalyst containing portion 42. For example, Fig. 15A is a side view showing a part of a straddle type vehicle of a fourth modification. Fig. 15B is a bottom view showing a part of a straddle type vehicle of a fourth modification. As shown in FIGS. 15A and 15B, the rib 55 extends from the engine 31 to a position lower than the catalyst containing portion 42. The rib 55 is provided in the crankcase 311. The rib 55 extends in the front-rear direction of the catalyst containing portion 42 on the side of the catalyst containing portion 42. In this case, the catalyst accommodating portion 42 can be protected from the stones or the like below the catalyst accommodating portion 42 by the ribs 55.

The engine unit 8 may also include a heat insulating member for the engine. For example, Fig. 16A is a side view showing a part of a straddle type vehicle of a fifth modification. Fig. 16B is a bottom view showing a part of the straddle type vehicle of the fifth modification. As shown in FIG. 16A and FIG. 16B, the engine heat insulating member 56 is disposed between the cooling fan device 33 and the catalyst containing portion 42. The engine heat insulating member 56 is disposed above the catalyst containing portion 42. The engine heat insulating member 56 is connected to the fan casing 45 of the cooling fan unit 33. When the cooling capacity of the cooling fan unit 33 is to be increased in this manner, by providing the heat insulating member 56 for the engine, the heat of the catalyst 36 can be suppressed from being transmitted to the cooling air of the cooling fan unit 33.

Fig. 17 is a bottom plan view showing a part of a straddle type vehicle of a sixth modification. As shown in FIG. 17, the engine heat insulating member 56 may be disposed between the engine 31 and the catalyst containing portion 42. lead The heat insulating member 56 is disposed on the side of the catalyst containing portion 42. The engine heat insulating member 56 is disposed between the crankcase 311 and the catalyst containing portion 42 in the vehicle width direction. An air guiding path 52, a first opening 53, and a second opening 54 are provided between the engine heat insulating member 56 and the catalyst containing portion 42. The first opening 53 communicates with the external space in front of the air guiding path 52. 2 Opening behind the air guiding path 52 is in communication with the external space.

In this case, heat transfer from the catalyst 36 to the engine 31 can be suppressed by the engine heat insulating member 56. Further, the traveling air 36 can be cooled by the traveling air passing through the air guiding path 52 from the first opening 53 and departing from the second opening 54. Thereby, the cooling performance of the catalyst 36 can be further improved.

The straddle type vehicle may also be provided with a heat insulating member for a fuel tank. The fuel tank heat insulating member is disposed between the fuel tank 7 and the catalyst containing portion 42. For example, Fig. 18A is a side view showing a part of a straddle type vehicle of a seventh modification. Fig. 18B is a bottom view showing a part of the straddle type vehicle of the seventh modification. As shown in FIGS. 18A and 18B, the fuel tank heat insulating member 57 is attached to the first connecting frame 17. The fuel tank heat insulating member 57 is disposed behind the fuel tank 7 and in front of the catalyst containing portion 42. In this case, heat transfer from the catalyst 36 to the fuel tank 7 can be suppressed.

The fuel tank heat insulating member 57 may be attached to a portion other than the first connecting frame 17 . For example, Fig. 19A is a side view showing a part of a straddle type vehicle of an eighth modification. Fig. 19B is a bottom view showing a part of the straddle type vehicle of the eighth modification. As shown in FIG. 19A and FIG. 19B, the fuel tank heat insulating member 57 is attached to the link mechanism 37.

The straddle type vehicle may also have a wind guiding member. For example, Fig. 20A is a side view showing a part of a straddle type vehicle of a ninth modification. Fig. 20B is a bottom view showing a part of the straddle type vehicle of the ninth modification. As shown in FIGS. 20A and 20B, the air guiding member 58 is disposed between the fuel tank 7 and the catalyst containing portion 42, and guides the traveling wind from the lower side of the fuel tank 7 toward the catalyst containing portion 42. The wind guide member 58 is a plate-shaped member and is disposed in a direction from the bottom of the fuel tank 7 toward the catalyst containing portion 42. The wind guide member 58 is attached to the first joint frame 17. In this case, the traveling wind flowing under the fuel tank 7 is directed toward the touch by the wind guiding member 58. The medium accommodating portion 42 guides and cools the catalyst 36. Thereby, the cooling performance of the catalyst 36 can be further improved. Further, the air guiding member 58 may be attached to a member other than the first connecting frame 17. For example, the wind guide member 58 may be attached to the link mechanism 37.

At least a portion of the catalyst containing portion 42 may be located behind the link mechanism 37. For example, Fig. 21 is a bottom view showing a part of a straddle type vehicle of a tenth modification. As shown in FIG. 21, a part of the catalyst containing portion 42 may be located behind the link mechanism 37. The link mechanism 37 includes a first link portion 37a and a second link portion 37b which are disposed to be spaced apart from each other. When looking up the vehicle, the exhaust port 314 is located between the first link portion 37a and the second link portion 37b. The first exhaust pipe 41 passes between the first link portion 37a and the second link portion 37b and is bent rearward. The catalyst containing portion 42 extends rearward. The catalyst containing portion 42 is located below the crankcase 311. In this case, as in the above-described embodiment, the catalyst containing portion 42 can be disposed as far as possible upstream, and the minimum ground clearance can be ensured to be large. Further, the catalyst accommodation portion 42 may not be limited to one portion of the catalyst storage portion 42 but the entire catalyst accommodation portion 42 may be located behind the link mechanism 37.

The shape of the body casing 6 may be any shape as long as at least a part of the catalyst containing portion 42 is located between the fuel tank 7 and the vehicle body casing 6 in the vehicle width direction. That is, as long as the wind passing between the fuel tank 7 and the vehicle body casing 6 is guided to the catalyst containing portion 42, the shape of the vehicle body casing 6 can be any shape.

In the above embodiment, the first opening 61 and the second opening 62 are provided on the bottom surface of the bottom case 22, and the third to fifth opening portions 63-65 are provided in the case case 69. However, the opening portion may be provided in other portions. For example, FIG. 22 is a bottom view showing a part of the straddle type vehicle 100 of the eleventh modification. As shown in FIG. 22, the bottom outer casing 22 includes a bottom outer casing 29. The bottom case 29 covers the fuel tank 7 from below. 23 is a side view of the straddle type vehicle 100 of the eleventh modification. As shown in FIG. 23, the opening portion 281 may be provided in a portion of the front outer casing 21 that is located behind the front wheel 4. Alternatively, the opening portion 282 may be provided in the first side bottom case 25. Alternatively, both the opening 281 and the opening 282 may be provided. Alternatively, the opening portion may be a gap between the joint portions of the outer casings of different bodies. Furthermore, as long as at least a portion of the opening is relatively flammable The rear end of the side of the magazine 7 is located further forward.

In the above embodiment, the fuel tank 7 includes the tank body 71 and the tank casing 79, but the tank casing 79 may be omitted.

The terms and expressions used herein are for the purpose of explanation and not for limitation. It is to be understood that the invention is not to be construed as a The invention can be embodied in a variety of different forms. The present disclosure should be considered as an embodiment of the principles of the invention. The embodiments are not intended to limit the invention to the preferred embodiments described herein and/or illustrated, and the embodiments are described herein. It is not limited to the embodiment described herein. The invention also includes all embodiments that include equivalent elements, modifications, deletions, combinations, improvements, and/or changes, which are understood by those skilled in the art. The limitation of the scope of application for patent application shall be interpreted broadly based on the terms used in the scope of the patent application, and shall not be limited to the embodiments described in the specification or the approval process of the present invention.

2‧‧‧ body frame

7‧‧‧fuel tank

8‧‧‧ engine unit

13‧‧‧1st bottom frame

14‧‧‧2nd bottom frame

15‧‧‧1st back frame

16‧‧‧2nd rear frame

17‧‧‧1st link frame

25‧‧‧1st bottom bottom shell

26‧‧‧2nd bottom bottom shell

31‧‧‧ Engine

32‧‧‧Transmission

33‧‧‧Cooling fan unit

34‧‧‧Exhaust pipe

35‧‧‧Muffler

36‧‧‧ catalyst

37‧‧‧ linkage mechanism

41‧‧‧1st exhaust pipe

42‧‧‧ Catalyst Containment Department

43‧‧‧2nd exhaust pipe

63‧‧‧3rd opening

64‧‧‧4th opening

65‧‧‧5th opening

71‧‧‧ box body

72‧‧‧1st outer casing installation

73‧‧‧2nd outer casing installation

74‧‧‧1st inclined part

75‧‧‧2nd inclined part

77‧‧‧1st box installation

78‧‧‧Second box installation department

79‧‧‧ box enclosure

311‧‧‧ crankcase

313‧‧‧ crankshaft

452‧‧‧Exhaust pipe outer casing

A1‧‧‧ arrow

A2‧‧‧ arrow

C3‧‧‧ center line

Claims (22)

A straddle-type vehicle includes: a vehicle body frame; a seat portion supported by the vehicle body frame; a flat foot pedal disposed further below and further forward than the seat portion; and a fuel tank disposed on the flat plate a vehicle body casing disposed on a side of the fuel tank; an opening portion for introducing a traveling wind between the fuel tank and the vehicle body casing; and an engine unit disposed on the plate foot a pedal and a rear of the fuel tank are rotatably supported by the vehicle body frame; and at least a portion of the engine unit is located below the seat portion; the engine unit includes: an engine having an exhaust port; an exhaust pipe; And the muffler is connected to the exhaust pipe; and the catalyst is disposed in the exhaust pipe; the exhaust pipe includes: a first exhaust pipe located at the catalyst Upstream, and connected to the exhaust enthalpy; the catalyst accommodating portion is connected to the first exhaust pipe and extends rearward to accommodate the catalyst; and the second exhaust pipe is located downstream of the catalyst Connected to the above touch Receiving portion is connected to the extending rearward muffler; when the vehicle in front view, the first exhaust pipe and at least a portion of the weight of the fuel tank At least a part of the catalyst containing portion is disposed behind a space between the fuel tank and the vehicle body casing. The straddle-type vehicle according to claim 1, wherein the cylinder axis of the engine is disposed in a direction crossing the vertical direction, and the rocking center of the engine unit and the catalyst containing portion are located below the cylinder axis, and the catalyst is At least a part of the catalyst containing portion is disposed behind the space between the fuel tank and the vehicle body casing in the entire rocking range of the accommodating portion. The straddle-type vehicle of claim 1, wherein the seat portion includes a seat portion for the rider to ride, the catalyst accommodation portion overlaps with the front seat portion in a front-rear direction of the vehicle, and at least a portion of the catalyst receiving portion When the vehicle is viewed from the side, the inner portion of the catalyst containing portion overlaps with the fuel tank when the vehicle is viewed in the forward direction. The straddle-type vehicle according to claim 1, wherein the fuel tank includes an inclined portion that is inclined upward and outward when the front view vehicle is present, and at least a part of the inclined portion and the catalyst containment when the vehicle is a front view The departments overlap. A straddle-type vehicle according to claim 4, wherein, in the forward-looking vehicle, at least a part of the inclined portion overlaps with the first exhaust pipe. The straddle type vehicle of claim 1, wherein the engine unit further includes a cooling fan device, At least a portion of the catalyst containing portion is located further forward than a center of rotation of the cooling fan device. The straddle-type vehicle according to claim 1, wherein the engine unit further includes a cooling fan device, and the cooling fan device and the catalyst containing portion are disposed on the same side with respect to a center line of a vehicle extending in a front-rear direction of the vehicle. The straddle-type vehicle of claim 1, wherein the body casing extends to a position further rearward than the fuel tank, and at least a portion of the catalyst accommodating portion does not overlap with the vehicle body casing when the vehicle is viewed from the side. A straddle-type vehicle according to claim 1, further comprising a link mechanism that connects the engine unit to the vehicle body frame, at least a part of the catalyst accommodation portion being located lateral to the link mechanism. The straddle-type vehicle according to claim 1, further comprising a link mechanism that connects the engine unit to the vehicle body frame, wherein at least a part of the catalyst storage portion is located behind the link mechanism when looking up the vehicle. The straddle-type vehicle of claim 1, further comprising a protective member disposed below the catalyst containing portion. A straddle-type vehicle according to claim 11, further comprising: a link mechanism that connects the engine unit to the vehicle body frame, wherein the protection member is attached to the link mechanism. A straddle-type vehicle according to claim 11, wherein said protective member is attached to said engine. The straddle-type vehicle of claim 11, wherein an air guiding path is disposed between the protective member and the catalyst receiving portion; The first opening communicates with the external space before the air guiding path; and the second opening communicates with the external space behind the air guiding path. A straddle-type vehicle according to claim 1, wherein said engine includes a rib extending to a position lower than said catalyst containing portion. The straddle-type vehicle according to claim 1, wherein the engine unit further includes: a cooling fan device disposed on a side of the engine; and an engine heat insulating member disposed in the cooling fan device and the catalyst housing portion between. The straddle-type vehicle according to claim 1, wherein the engine unit further includes an engine heat insulating member disposed between the engine and the catalyst containing portion. The straddle-type vehicle according to claim 16, wherein the engine heat insulating member and the catalyst containing portion are provided with: an air guiding path; and a first opening that communicates with an external space before the air guiding path And a second opening that communicates with the external space behind the air guiding path. The straddle-type vehicle according to claim 1, further comprising a heat insulating member for a fuel tank disposed between the fuel tank and the catalyst containing portion. The straddle-type vehicle according to claim 1, further comprising a wind guide member disposed between the fuel tank and the catalyst accommodating portion, and driving wind from a lower side of the fuel tank toward the catalyst accommodating portion guide. The straddle-type vehicle according to claim 1, wherein at least a part of the catalyst containing portion is located below the bottom surface of the fuel tank in a state where the engine unit is located at a lowest position in the rocking range. The straddle-type vehicle according to any one of claims 1 to 21, wherein the vehicle body frame includes a bottom frame extending downward and rearward through the flat footboard, and in the front view vehicle, the catalyst receiving portion At least a portion is located below the bottom frame.