JPH0825500B2 - Intake and exhaust structure of saddle type vehicle for running on rough terrain - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an intake / exhaust structure for a saddle-ride type vehicle for running on uneven terrain, and more particularly to a multiple cylinder engine equipped with a plurality of carburetors in the vehicle width direction. The present invention relates to narrowing the vehicle width when the outside air is introduced through the exhaust gas and the exhaust gas is exhausted by a plurality of exhaust pipes along both sides of the body frame.

[Conventional technology]

Generally, saddle riding type vehicles for running on rough terrain have wheels with wide ultra-low pressure tires (so-called balloon tires) mounted at the front and rear of the body frame, a single cylinder engine mounted at approximately the center, and a carburetor connected to these. A saddle type seat is mounted above the. In recent years, there has been a strong demand for higher output in this type of vehicle, and the applicant of the present invention has proposed a vehicle that can meet this demand, for example, left and right 2
We proposed a vehicle equipped with an engine equipped with two cylinders and connecting two carburetors to the left and right (see Japanese Patent Application No. 61-20148).

[Problems to be solved by the invention]

By the way, it is desirable that the vehicle width of this kind of rough terrain vehicle is as narrow as possible for the purpose of traveling on rough terrain to improve the handleability. However, in a vehicle equipped with the above-described multi-cylinder engine, depending on the design, the width of an intake / exhaust device for introducing outside air into the plurality of carburetors and discharging exhaust gas from the engine to the rear of the vehicle becomes wider. It may not be possible to meet the demand for narrowing the vehicle width.

Therefore, an object of the present invention is to provide an intake / exhaust structure that can meet the demand for narrowing the vehicle width in a saddle type vehicle for traveling on rough terrain equipped with a multi-cylinder engine.

[Means for solving problems]

The present invention provides a multi-cylinder engine, and in an all-terrain traveling pre-saddle type vehicle in which a plurality of carburetors in the vehicle width direction are connected to the engine, while introducing a mixture into the engine through the plurality of carburetors. The exhaust gas structure has a plurality of exhaust pipes arranged on both sides of the vehicle body frame and discharges exhaust gas toward the rear of the vehicle. One structure is provided below the central portion of the seat 8 in the front-rear direction and behind the carburetor 4. An air cleaner body 5 having a shorter width in the vehicle width direction than the length in the front-rear direction is arranged, and the air cleaner body 5 and the two carburetors 4 are aligned in the vehicle width direction and are located below the front part of the seat. Two connecting pipes 5a
And the upper portion of the air cleaner body 5 is bulged to a width narrower than the space between the pair of left and right seat rails 2c, 2c and substantially the same height as the left and right seat rails 2c, 2c. At the front end of the bulging portion 5d, one outside air introducing pipe 5b narrower than the bulging portion 5d is connected and formed so as to be located above the connecting pipe 5a, and the two exhaust pipes 6 and 6 are connected to the air cleaner. At the lateral position of the main body, it overlaps in the vicinity of the lower part of the seat rail 2c in a plan view, and at the lateral position of the outside air introducing pipe, the width is narrower than the mutual distance between the air cleaner main body lateral portions a and at least a part thereof c. Are arranged so as to overlap with the connecting pipe 5a in a plan view, the outside air introducing pipe 5b is extended obliquely upward to the vehicle front side, and the front end opening 5c is formed by the rear portion of the fuel tank 7 and the front portion of the seat 8. The exhaust pipe 6 is positioned higher than the exhaust pipe 6.

[Action]

In the intake / exhaust structure for a saddle-ride type vehicle for running on uneven terrain according to the present invention, the two carburetors 4 are assembled into an air cleaner body 5 having a width narrower than the distance between the left and right seat rails 2c, 2c, and the air cleaner body By this, one narrow outside air introduction pipe 5b is connected and formed on the upper part of 5, and the pair of left and right exhaust pipes 6, 6 are overlapped with the air cleaner body side portion a under the seat rails 2c, 2c. Also, the outside air introduction pipe side portion b is the side portion a.
The width of the exhaust pipe is narrower than that of the exhaust pipe, and at least a part of the pipe overlaps the connecting pipe 5a, so the exhaust pipe can be narrowed while securing a sufficient air cleaner capacity in a 2-cylinder, 2-carburetor engine. As a result, the vehicle width can be narrowed to improve the riding posture.

Further, since the outside air introduction pipe 5b is extended obliquely upward and the front end opening 5c is located in the space surrounded by the rear portion of the fuel tank and the front portion of the seat, the front end opening 5c is located at a high place, and therefore, for example, underwater. It is possible to prevent water from being sucked from the outside air introduction pipe during traveling or the like. Also, the temperature of the air rises due to the exhaust pipes 6c, 6c arranged on both the left and right sides of the outside air introduction pipe 5b, but since the front end opening 5c is located higher than the exhaust pipe, the heat of the exhaust pipe causes It is possible to suppress the intake of air whose temperature has risen.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 are views for explaining an intake / exhaust structure according to an embodiment of the present invention. In the figure, 1 is a saddle riding type vehicle for running on uneven terrain to which the present embodiment is applied. A vehicle body frame 2 of the vehicle 1 has a pair of left and right cradle-shaped side pipes 2a connected by a cross pipe 2b, It is of a double cradle type in which a seat rail 2c is connected to the rear portion of this. A front wheel suspension device 11 is provided at the front of the body frame 2.
A front wheel 12 is mounted via the rear wheel 10 via a rear arm 9a having a rear wheel suspension device 9 at the rear.
A front fender device 16 and a rear fender device 15 are arranged above the rear wheels 10 and 12, respectively. Further, a radiator 20, a steering shaft 13, a fuel tank 7, and a saddle type seat 8 are sequentially mounted on the upper portion of the vehicle body frame 2 from the front.

A water-cooled two-cycle two-cylinder engine 3 is mounted substantially in the center of the body frame 2. The engine 3
The left and right carburetors 4 are connected to the intake sides of the left and right cylinders. An air cleaner body 5 is disposed behind the carburetor 4, and the air cleaner body 5 is connected to the left and right carburetors 4 by the left and right connecting pipes 5a.
A bulge portion 5d that is narrower than the left and right seat rails 2c, 2c and bulges to the same height as both rails is formed on the upper portion of the air cleaner body 5. An outside air introduction pipe 5b for introducing outside air is connected to the center in the vehicle width direction. The outside air introduction pipe 5b extends forward between the left and right connecting pipes 5a, passes upward, and is bent upward. The opening 5c of the outside air introducing pipe 5b is located between the fuel tank 7 and the seat 8, and the tank cover 7a of the fuel tank 7 is integrally formed with an umbrella portion 7b for covering the opening 5c.

The left and right exhaust pipes 6 of the engine 3 are composed of a left and right exhaust expansion pipes 6a, a conducting pipe 6c and a silencer 6b. The exhaust expansion pipe 6a is led out in front of the engine 3 and wound in a cochlea shape, and the conducting pipe 6c is the exhaust expansion pipe 6a.
It is connected to the rear ends of the left and right carburetors 4 and the left and right connecting pipes 5a, and extends rearward through the outside air introducing pipe 5b and the left and right sides of the air cleaner body 5. The left and right seat rails 2c are bent inward from the left and right side pipes 2a, and then extend rearward so as to cover the left and right conducting pipes 6c. That is, the side portion a of the conduction pipe 6c on the side of the air cleaner body is positioned near the lower portion of the seat rail 2c so as to overlap therewith, and the portion b on the side of the outside air introduction pipe b.
Is narrower than the space between the side portions a of the air cleaner main body, and is a part c of the left side conducting pipe 6c.
Overlaps with the left connecting pipe 5a. And this conduit 6c
The silencer 6b is connected to the rear end of the rear fender device 15. The silencer 6b is located below the connection between the central fender portion 15a of the rear fender device 15 and the left and right fender portions 15b. A cooling hole 15 for introducing cooling air is provided above the muffler 6b at the connecting portion.
c is formed.

 Next, the function and effect of this embodiment will be described.

In general, when the outside air is introduced into a two-cylinder engine through two carburetors and the exhaust gas is discharged through two exhaust pipes, the exhaust pipes pass outside in the vehicle width direction depending on the design. There is a problem that the width becomes wider.
On the other hand, in this embodiment, the left and right carburetors 4 and the air cleaner body 5 are connected by the left and right connecting pipes 5a, and
Since the conducting pipe 6c portion of the exhaust pipe 6 is arranged so as to pass above the left and right connecting pipes 5a and to the side of the outside air introducing pipe 5b arranged in the center in the vehicle width direction, the conducting pipe 6c is only that much. Can be moved closer to the inner side in the vehicle width direction, and as a result, the vehicle width can be reduced.

Further, in this embodiment, the outside air introducing pipe 5b is connected to the left and right connecting pipes 5a.
Since it is arranged between and above, the interference with the carburetor 4 can be avoided, and since the opening 5c is located at a high place when viewed from the whole vehicle, for example, underwater traveling where the wheels are submerged. The waterproof effect can be improved. Further, since the opening 5c is covered with the umbrella portion 7b, it is possible to prevent, for example, rainwater or the like that has entered through the tank cover 7a from entering the opening 5c, and also from this point, the waterproof property can be improved.

Furthermore, since the cooling hole 15c is formed in the upper portion of the muffler 6b of the rear fender device 15, the traveling wind is introduced through the cooling hole 15c and cools the muffler 6b, and as a result, the surroundings of the muffler 6b. Can prevent overheating.

In the above embodiment, the outside air introducing pipe 5b was opened above the connecting pipe 5a, but this introducing pipe 5b does not necessarily have to be opened at this position, and is connected to, for example, the main pipe,
External air may be introduced through the pipe.

〔The invention's effect〕

As described above, according to the intake / exhaust structure for a saddle-ride type vehicle for running on uneven terrain according to the present invention, the outside air introduction pipe having a width narrower than that of the outside air introduction pipe is provided in the upper bulging portion of the acrina main body having a width narrower than the seat rail interval. A pair of left and right exhaust pipes are connected to each other, and the side portion of the air cleaner body overlaps with the vicinity of the lower part of the seat rail, and the side portion of the outside air introduction pipe is narrower than the space between the side portions of the air cleaner body. , Furthermore, since at least one of the exhaust pipes is arranged so as to partially overlap with the connecting pipe, it is possible to narrow the width of the exhaust pipes while ensuring a sufficient air cleaner capacity in a two-cylinder, two-carburetor engine. This has the effect of narrowing the vehicle width and improving the riding posture.

Further, since the outside air introduction pipe is extended obliquely upward and the front end opening is located in the space surrounded by the rear part of the fuel tank and the seat front part and higher than the exhaust pipe, water is sucked from the outside air introduction pipe. It is possible to prevent the above, and to suppress the inhalation of the air whose temperature has risen.

[Brief description of drawings]

1 to 5 are views for explaining an intake / exhaust structure according to an embodiment of the present invention. FIG. 1 is a plan view around the air cleaner, FIG. 2 is a side view thereof, and FIG. Thereafter, a plan view of the fender device portion, FIG. 4 is a side view of a saddle riding type vehicle for traveling on uneven terrain, and FIG. 5 is a plan view thereof. In the figure, 1 is a saddle-ride type vehicle for running on uneven terrain, 2 is a body frame, 3 is an engine, 4 is a carburetor, 5 is an air cleaner body, 5a is a connecting pipe, 5b is an outside air introducing pipe, and 6c is a conducting pipe (exhaust pipe). Tube).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-89187 (JP, A) real-open Sho-58-82420 (JP, U) real-open Sho-60-158921 (JP, U) real-open Sho-60- 49020 (JP, U) Actual opening Sho 56-118193 (JP, U) Actual opening Sho 60-36325 (JP, U) Actual opening Sho 60-161618 (JP, U)

Claims (1)

[Claims] 1. A saddle-type seat is mounted on a pair of left and right seat rails located at an upper rear portion of a body frame, and the saddle-type seats are arranged substantially at the center of the body frame in the front-rear direction in the vehicle width direction.
In a saddle riding type vehicle for running on rough terrain in which an engine having two cylinders is mounted and two carburetors arranged in the vehicle width direction are connected to the engine, a mixture for combustion is introduced into the engine through the carburetor. Along with the intake / exhaust structure in which exhaust gas from the engine is exhausted toward the rear of the vehicle by two exhaust pipes along both sides of the vehicle body frame at a high place near the seat, the seat is substantially centered in the front-rear direction. A narrow air cleaner body having a shorter vehicle width direction length than the front-rear direction length is disposed below the portion and behind the carburetor, and the air cleaner body and the two carburetors are arranged in the vehicle width direction. The air cleaner body is connected by two connecting pipes located below the front part of the seat, and the upper portion of the air cleaner body is narrower than the space between the pair of left and right seat rails, and the left and right seat rails are substantially separated from each other. The outside air introducing pipe having a width narrower than that of the bulging portion is connected to the front end of the bulging portion so as to be located above the connecting pipe, and the two exhaust pipes are connected to the air cleaner. At the side position of the main body, it overlaps in the vicinity of the lower part of the seat rail in a plan view, and at the side position of the outside air introduction pipe, the width is narrower than the mutual interval at the side part of the air cleaner main body and at least a part thereof is seen in a plan view. The outside air introduction pipe is extended obliquely upward to the vehicle front side, and the front end opening thereof is in the space formed by the rear part of the fuel tank and the front part of the seat and the exhaust pipe. An intake / exhaust structure for a saddle type vehicle for traveling on uneven terrain, which is characterized by being placed at a higher place.