JP6012483B2 - Exhaust device for saddle riding type vehicle - Google Patents

Description

  The present invention relates to an exhaust device for a straddle-type vehicle that suppresses an increase in space and secures a movable range of a front wheel while improving catalytic activity.

In a motorcycle equipped with an internal combustion engine, a plurality of exhaust pipes for exhausting combustion exhaust gas are provided, and a plurality of catalyst devices for purifying exhaust gas are arranged in the exhaust pipe. It is shown.
However, in the one shown in Patent Document 1 below, since the catalyst device that is normally used at a high temperature is disposed below the internal combustion engine, the exhaust gas passing through the piping is cooled while going to the catalyst, and the catalyst device It may take a long time to activate.

Japanese Patent No. 4533756 (FIGS. 1, 7, and 13)

  In view of the above-described prior art, the present invention is a straddle-type vehicle that suppresses an increase in space and can promote early activation of the catalyst device while ensuring a movable range of the front wheels, and can improve catalytic activity. It is an object to provide an exhaust device.

  In order to solve the above-mentioned problem, an invention according to claim 1 is characterized in that an internal combustion engine is supported on a body frame, a front wheel is disposed in front of the internal combustion engine, and a plurality of exhaust pipes are provided at a front portion of the internal combustion engine. In the exhaust device of a saddle-ride type vehicle that is connected and accommodates a primary catalyst device and a secondary catalyst device downstream thereof in the middle of exhaust paths of the plurality of exhaust pipes, the primary catalyst device includes the plurality of exhaust pipes The exhaust device for a saddle-ride type vehicle is characterized in that a part of the exhaust pipe is disposed in front of the crankcase of the internal combustion engine and behind the front wheel in a vehicle width direction.

  According to a second aspect of the present invention, in the exhaust system for a saddle-ride type vehicle according to the first aspect, the plurality of exhaust pipes are connected to a muffler disposed on one side in the vehicle width direction, and The primary catalyst device is housed in a longer exhaust path.

  According to a third aspect of the present invention, in the exhaust device for a saddle-ride type vehicle according to the first or second aspect, the vehicle body frame has a down tube that descends from the head pipe to the lower rear portion. And a lower frame that branches bifurcated from the lower end of the vehicle toward the rear of the vehicle, and the primary catalyst device is disposed between the left and right lower frames in a front view of the vehicle.

  According to a fourth aspect of the present invention, in the exhaust system for a saddle-ride type vehicle according to the third aspect, an oil filter is attached to a front portion and a lower portion of the internal combustion engine. The oil filter is disposed so as to overlap with the oil filter.

  According to a fifth aspect of the present invention, in the exhaust device for a saddle-ride type vehicle according to the fourth aspect, the primary catalyst device is disposed in front of the lower frame in a side view of the vehicle.

According to a sixth aspect of the present invention, in the exhaust system for a saddle riding type vehicle according to any one of the first to fifth aspects, an exhaust pipe including the primary catalyst device among the plurality of exhaust pipes. Is characterized in that an O ₂ sensor is disposed between a connection portion with an internal combustion engine and the primary catalyst device, and the O ₂ sensor is attached to protrude rearward in a side view of the vehicle.

  According to a seventh aspect of the present invention, in the exhaust system for a saddle-ride type vehicle according to any one of the first to sixth aspects, the plurality of exhaust pipes on the downstream side of the primary catalyst device. And a tube bundle portion integrally formed so as to bundle the plurality of exhaust pipes on the upstream side of the collective portion. The secondary catalyst device is provided in the collective portion. Is arranged.

  According to the exhaust system for a saddle-ride type vehicle according to the first aspect of the present invention, the primary catalyst device is moved upstream of the exhaust path in front of the crankcase, and the front and rear wheels are disposed behind the front wheels while restricting the vertical and longitudinal spaces. Therefore, it is possible to transmit exhaust heat to the primary catalyst device through a short exhaust path to promote early activation of the primary catalyst device and to secure the movable range of the front wheels.

  According to the invention of claim 2, in addition to the effect of the invention of claim 1, the primary catalyst device is accommodated in a part of the plurality of exhaust pipes having a longer path, that is, a part of the exhaust pipe far from the muffler. Therefore, the primary catalyst device is provided in the exhaust pipe routed from the exhaust port far from the muffler of the internal combustion engine to the muffler side, and heat is applied to the primary catalyst device before the exhaust heat cools down in a short exhaust path. Communicating can promote early activation.

  According to the invention of claim 3, in addition to the effect of the invention of claim 1 or claim 2, the primary catalyst device is disposed between the bifurcated lower frames at the vehicle width direction position. The device can be arranged close to the internal combustion engine, and the movable range of the front wheels can be further ensured.

  According to the invention of claim 4, in addition to the effect of the invention of claim 3, the oil filter located behind is protected by the primary catalyst device and the exhaust pipe provided with the primary catalyst device. Further, since the primary catalyst device is disposed between the bifurcated lower frame at the position in the vehicle width direction, the oil filter is also protected on the left and right by the lower frame.

  According to the invention of claim 5, in addition to the effect of the invention of claim 4, between the oil filter attached to the lower part of the internal combustion engine and the exhaust pipe provided in front of the lower frame and provided with the primary catalyst device. The space for inserting the oil filter replacement tool can be secured, and the oil filter can be replaced without having to remove the exhaust pipe.

According to the invention of claim 6, in addition to the effect of the invention of any one of claims 1 to 5, since the O ₂ sensor is mounted so as to protrude rearward in a vehicle side view, the primary catalyst device The movable range of the front wheels can be further secured in front of the exhaust pipe provided with

  According to the invention of claim 7, in addition to the effect of the invention of any one of claims 1 to 6, a plurality of exhaust pipes are integrally formed in the tube bundle portion downstream of the primary catalyst device. Therefore, the heat of the primary catalyst device can be transmitted to the other exhaust pipe, and the exhaust gas in the other exhaust pipe can be heated in advance, so that the exhaust gas purification in the secondary catalyst device in the collecting section can be promoted.

1 is a right side view of a motorcycle including an exhaust device for a saddle riding type vehicle according to an embodiment of the present invention, with a cover and the like removed. 1 is a left side view of a body frame and an internal combustion engine in a motorcycle according to an embodiment. FIG. 3 is a front view of a body frame and an internal combustion engine of the motorcycle as viewed in the direction of arrows III-III in FIG. 2.

A straddle-type vehicle exhaust device according to an embodiment of the present invention will be described with reference to FIGS.
In the description and claims of the present specification, the directions such as front, rear, left, right, up, down, etc. refer to a vehicle (saddle type vehicle) in a state where the exhaust device of the saddle type vehicle according to the present embodiment is mounted on the saddle type vehicle. ).
In the figure, arrow FR indicates the front of the vehicle, LH indicates the left side of the vehicle, RH indicates the right side of the vehicle, and UP indicates the upper side of the vehicle.
In the present embodiment, the saddle riding type vehicle is a motorcycle.

  FIG. 1 is a right side view of the motorcycle 1 according to an embodiment of the present invention with the cover and the like removed. The body frame 2 of the motorcycle 1 includes a head pipe 20, a pair of left and right main frames 21 extending obliquely rearward from the head pipe 20, and a pair of left and right center frames 22 extending downward from the rear end of the main frame 21. And a single down tube 23 extending downward and downward from the head pipe 20 at a steep angle, connected to the lower end 23a of the down tube 23, bifurcated in a bifurcated manner, and then lowered through the curved portion 24a. And a pair of left and right lower frames 24 connected to the lower ends of the pair of left and right center frames 22 and a seat stay 25 extending slightly upward from the upper and lower portions of the center frame 22.

A front fork 12 that supports the front wheel 11 is supported on the head pipe 20 so as to be steerable, and a steering handle 13 is connected to the front fork 12.
The front fork 12 incorporates a spring and a damper (not shown) and expands and contracts in the axial direction to give a movable range of a certain stroke to the front wheel 11 in addition to turning by steering.

  A rear fork 15 that supports the rear wheel 14 is supported so as to be able to swing up and down with a pivot portion 26 at the lower portion of the center frame 22 as a fulcrum. A link is provided between the upper portion of the center frame 22 and the rear fork 15. A rear cushion unit (not shown) is provided via the mechanism 16.

  The internal combustion engine 3 of the present embodiment includes a transmission 5 integrally in the rear part of the crankcase 30 to constitute a so-called “power unit”, and the crankshaft 31 has its axis X as the center of the motorcycle 1. 1 is a water-cooled in-line two-cylinder four-stroke cycle internal combustion engine that is oriented in the vehicle width direction, that is, the left-right direction and is mounted on the motorcycle 1.

  The internal combustion engine 3 is supported by the down tube 23, the lower frame 24, and the center frame 22 behind the front wheel 11, and the power of the internal combustion engine 3 is output sprocket 51 and rear wheels of the transmission 5 incorporated in the internal combustion engine 3. It is transmitted to the rear wheel 14 via the drive chain 17. A fuel tank 18 is mounted on the left and right main frames 21 so as to be positioned above the internal combustion engine 3, and a tandem seat 19 for drivers and passengers is mounted on the center frame 22 and the seat stay 25. It has been.

FIG. 2 shows a left side view of the body frame 2 and the internal combustion engine 3 in the motorcycle 1.
As shown in FIG. 2, the internal combustion engine 3 has a cylinder block 33 integrally formed with a forward tilt at a front upper portion of a crankcase 30, and a cylinder head 34 fastened to the upper portion of the cylinder block 33. A cylinder head cover 35 fastened to the top of the head 34 covers the cylinder head 34.
In the cylinder block 33, two cylinder bores (not shown) with the cylinder shaft tilted forward are arranged in the vehicle body width direction, and slidably fit into the cylinder bores 31 on the crankshaft 31 oriented in the vehicle width direction. A piston (not shown) is connected via a connecting rod.

An intake system (not shown) is connected to the intake port 36 of each cylinder bore at the rear of the cylinder head 34, and an exhaust pipe 8L for the left port is connected to each exhaust port 37 of each cylinder bore at the front of the cylinder head 34. The exhaust pipe 8R of the port is connected, and the left and right port side exhaust pipes 8L, 8R are connected to the pipe bundle part 82 integrally formed on the lower right side of the crankcase 30, and the pipe bundle part 82 collects both the exhaust pipes 8L, 8R together. And a muffler 80 (see FIG. 1) disposed on the right side of the vehicle, specifically, on the upper right side of the rear wheel 14 , via an integrated collecting portion 81 to be joined together.

  As shown in FIG. 2, the internal combustion engine 3 is distributed left and right on the front lower front surface of the crankcase 30 so as to protrude forward, and the left engine hanger 61 </ b> L integrally formed with the crankcase 30, 61R, a left second engine hanger 62L and a right second engine hanger 62R that are formed integrally with the crankcase 30 and project forward from the front upper portion of the crankcase 30, that is, the front upper portion of the cylinder block 33. And a left third engine hanger 63L and a right third engine hanger 63R that are formed integrally with the crankcase 30 so as to protrude upward and to the left and right of the rear upper part of the crankcase 30.

On the other hand, left hanger bracket 27L and right hanger bracket 27R extending toward the inside of the curved portion 24a are welded and fixed to the vehicle body frame 2 at the curved portions 24a of the left and right lower frames 24.
Near the lower end of the down tube 23, a left second hanger bracket 28L and a right second hanger bracket 28R that extend rearward are fastened to the left and right.
A left third hanger bracket 29L and a right third hanger bracket 29R extending forward are welded and fixed to the upper portions of the left and right center frames.

  The left and right engine hangers 61L and 61R are fastened to the left and right hanger brackets 27L and 27R on the vehicle body frame 2 side, and the left and right second engine hangers 62L and 62R are connected to the left and right sides on the vehicle body frame 2 side. The left and right third engine hangers 63L and 63R are fastened to the second hanger brackets 28L and 28R. The left and right third hanger brackets 29L and 29R are fastened to the left and right third hanger brackets 29L and 29R. Mounted and fixed.

  Here, as shown in FIG. 3 which is a front view of the body frame 2 and the internal combustion engine 3 of the motorcycle 1 when the state of FIG. 2 is viewed from the front of the vehicle, and with reference to FIG. In the vehicle body frame 2, the down tube 23 descends downward from the head pipe 20 at a steep angle. Yes.

The left and right exhaust pipes 8L and 8R connected to the exhaust port 37 of each cylinder bore extend downward in front of the down tube 23 (see FIGS. 1 and 2) and are below the branch portion 24b of the lower frame 24. , The exhaust pipe 8L of the left port is forward (B in FIG. 1) and closer to the lower side than the crankcase 30 and behind the movable range (A in FIG. 1) of the front wheel 11 (A ′ in FIG. 1). It is bent from the left side to the right side, and is then connected to a tube bundle portion 82 that is formed side by side with the exhaust pipe 8R of the right port and around the lower right side of the crankcase 30 so that the exhaust pipes 8L and 8R are integrally formed. .
The tube bundle portion 82 is connected to an integral collecting portion 81 where the exhaust pipes 8L and 8R are joined together, and is connected to a muffler 80 disposed on the upper right side of the rear wheel 14 .

Inside the portion 8La (between A ′ and B in FIG. 1) of the left port exhaust pipe 8L that is bent from the left side to the right side in the vehicle width direction, a primary catalyst device 9A having an exhaust gas purifying catalyst is installed in the vehicle. The exhaust gas is disposed in the width direction, purifies the exhaust gas flowing through the exhaust pipe 8L, and heats the exhaust gas by a catalytic reaction.
Accordingly, the primary catalyst device 9A is disposed in front of the crankcase 30 and in front of the lower end portion 23a of the down tube 23 (see FIG. 2), and is disposed between the left and right lower frames 24 in a vehicle front view (see FIG. 2). (See FIG. 3).

An oil filter 4 is attached to the front and lower portion of the crankcase 30 of the internal combustion engine 3 between the left and right engine hangers 61L and 61R, and an exhaust pipe connected to the left exhaust port 37 is attached. 8L and the primary catalyst device 9A provided therein are located in front of the oil filter 4, and the primary catalyst device 9A and the oil filter 4 overlap each other when the vehicle is viewed from the front (see FIG. 3).
Therefore, a space for inserting an oil filter replacement tool between the oil filter 4 attached to the lower part of the internal combustion engine 3 and the exhaust pipe 8L provided with the primary catalyst device 9A located in front of the left and right lower frames 24. The oil filter 4 can be replaced without having to remove the exhaust pipe 8L.

As shown in the figure, in the exhaust pipe 8L provided with the primary catalyst device 9A, exhaust gas for operation control is provided between the exhaust port 37 and the primary catalyst device 9A, which are connected to the internal combustion engine 2. An O ₂ sensor 38 for detecting the air-fuel ratio from the component is disposed, and the O ₂ sensor 38 is mounted so as to protrude rearward in a side view of the vehicle, and the movable range A of the front wheel in front of the exhaust pipe 8L is It is more fully secured without being hindered.

As shown in FIG. 1, the exhaust pipe 8L on the downstream side of the primary catalyst device 9A and the exhaust pipe 8R connected to the right exhaust port 37 are arranged side by side on the right side of the lower part of the crankcase 30. Connected to the integrally formed tube bundle portion 82, the tube bundle portion 82 is connected near the lower end of the center frame 22 on the right side to an integrated collection portion 81 that joins both the exhaust pipes 8L and 8R together. Is provided with a secondary catalyst device 9B.
Therefore, the exhaust gas that has passed through the primary catalyst device 9A from the exhaust pipe 8L on the left port and the exhaust gas from the exhaust pipe 8R on the right port both flow into the gathering portion 81, merge, and are mixed to form the secondary catalyst device 9B. Purified by.

At that time, the integrally formed tube bundle portion 82 can transfer the heat of the primary catalyst device 9A in the exhaust pipe 8L of the left port to the exhaust pipe 8R of the right port so that the exhaust of the exhaust pipe 8R can be preheated. The purification of the exhaust gas in the secondary catalyst device 9B in the collecting portion 81 can be promoted.
The purified exhaust gas is sent to the muffler 80 connected to the downstream side of the collecting portion 81 and then exhausted.

  As described above, in the exhaust system for a saddle-ride type vehicle according to the present embodiment, the exhaust gas temperature of the left-side port exhaust pipe 8L, which is a part of the plurality of exhaust pipes 8L, 8R, is increased by catalytic reaction. The secondary catalyst device 9B for providing the main exhaust gas purification action is provided with a plurality of exhaust pipes 8L and 8R on the downstream side of the primary catalyst device 9A. It is provided in the gathering portion 81 formed integrally.

Accordingly, when the temperature of the secondary catalyst device 9B is not sufficiently increased and the activity of the catalyst is not increased, such as when the internal combustion engine 3 is started, first, the exhaust gas of the internal combustion engine 3 is partially exhausted from the exhaust pipe 8L. The primary catalyst device 9A provided at a position close to the exhaust port 37 is first heated and activated early, and the downstream secondary catalyst device 9B is exhausted by the exhaust gas heated by the catalytic reaction in the primary catalyst device 9A. However, it is heated, and its catalytic activity can be rapidly increased.
At that time, in the integrally formed tube bundle portion 82 , the heat generated by the primary catalyst device 9A in the exhaust pipe 8L of the left port is transmitted to the exhaust pipe 8R of the right port, and the exhaust of the exhaust pipe 8R can be preheated. Therefore, it is possible to promote the heating of the secondary catalyst device 9B in the collecting portion 81 and the catalyst activity increase.

If the primary catalyst device 9A is provided in both the exhaust pipes 8L and 8R, the exhaust gas is always sent to the secondary catalyst device 9B after passing through the primary catalyst device 9A. As in the embodiment, since the other exhaust pipe 8R is not provided with the primary catalyst device 9A, there is no increase in exhaust resistance, and the entire exhaust pipe 8L, 8R is used for exhaust gas heating at the time of startup or the like. The influence on the exhaust efficiency due to the provision of the primary catalyst device is suppressed.
Since the exhaust gas purification is performed by the secondary catalyst device 9B which is the main exhaust gas purification catalyst, the primary catalyst device 9A mainly for the purpose of heating the exhaust gas and increasing the catalyst activity is provided in some exhaust pipes 8L. It is effective enough.

  Further, the primary catalyst device 9A has an exhaust pipe 8L on the left port arranged on the far side of the muffler 80 and the secondary catalyst device 9B of the collecting portion 81, that is, an exhaust pipe having a longer path among the plurality of exhaust pipes 8L and 8R. 8L is accommodated in this manner, so that a location 8La that is bent from the left side to the right side in the vehicle width direction of the exhaust pipe 8L and is oriented in the vehicle width direction can be used as a location where the primary catalyst device 9A is disposed. Early activation is achieved by transferring heat to the primary catalyst device 9A before the exhaust heat cools down, and the primary catalyst device 9A is disposed in the exhaust pipe 8L so as to lie in the width direction of the vehicle. The length in the vehicle length direction is compact.

The characteristics of the exhaust system of the saddle riding type vehicle according to the present embodiment will be described below in a lump.
That is, the internal combustion engine 3 is supported by the vehicle body frame 2, the front wheel 11 is disposed in front of the internal combustion engine 3, the left and right exhaust pipes 8L and 8R are connected to the front portion of the internal combustion engine 3, and the left and right exhaust pipes 8L , 8R in the exhaust system of the saddle-ride type vehicle that accommodates the primary catalyst device 9A and the downstream secondary catalyst device 8B in the middle of the exhaust path, the primary catalyst device 9A is provided on the left side of the left and right exhaust pipes 8L, 8R. In the exhaust pipe 8L, the exhaust pipe 8L is disposed in front of the crankcase 30 of the internal combustion engine 3 and rearward of the front wheel 11 in a vehicle width direction.

  Therefore, the primary catalyst device 9L can be arranged so as to avoid the movable range of the front wheel 11 behind the front wheel 11 while placing the primary catalyst device 9L upstream of the exhaust path in front of the crankcase 30 while restraining the vertical vertical space. The exhaust heat is transmitted to the primary catalyst device 9A through a short exhaust path to promote early activation of the primary catalyst device 9A, and the movable range of the front wheels 11 can be secured.

  The left and right exhaust pipes 8L and 8R are connected to a muffler 80 disposed on the right side in the vehicle width direction, and the primary catalyst device is connected to the left exhaust pipe 8L having a longer path between the left and right exhaust pipes 8L and 8R. 9L is accommodated, that is, because it is accommodated in the left exhaust pipe 8L that is far from the muffler 80, the primary catalyst device 9L is connected to the muffler 80 side from the exhaust port 37 that is far from the muffler 80 of the internal combustion engine 3. By providing heat to the primary catalyst device 9A before the exhaust heat is cooled in a short exhaust path, early activation of the primary catalyst device 9A can be promoted.

  The vehicle body frame 2 has a down tube 23 that descends downward from the head pipe 20 and a lower frame 24 that bifurcates from the lower end portion 23a of the down tube 23 toward the rear of the vehicle. Since the device 9A is disposed between the left and right lower frames 24 when the vehicle is viewed from the front, the primary catalyst device 9A can be disposed close to the internal combustion engine 3 to further ensure the movable range of the front wheels 11. it can.

  Further, the oil filter 4 is attached to the front part and the lower part of the internal combustion engine 3, and the primary catalyst device 9A and the oil filter 4 are arranged so as to overlap each other when viewed from the front of the vehicle. Further, the oil filter 4 located behind is protected by the exhaust pipe 8L, and the primary catalyst device 9A is disposed between the bifurcated lower frame 24 at the position in the vehicle width direction. The oil filter 4 is protected on the left and right.

  Further, since the primary catalyst device 9A is disposed in front of the lower frame 24 in a side view of the vehicle, the oil filter 4 attached to the lower part of the internal combustion engine 3 and the primary catalyst device 9A positioned in front of the lower frame 24 are arranged. A space for inserting an oil filter replacement tool can be secured between the provided exhaust pipe 8L and the oil filter 4 can be replaced without having to remove the exhaust pipe 8L.

Of the left and right exhaust pipes 8L and 8R, the exhaust pipe 8L provided with the primary catalyst device 9A is provided with an O ₂ sensor 38 between the exhaust port 37 which is a connecting portion with the internal combustion engine 3 and the primary catalyst device 8L. In addition, since the O ₂ sensor 38 is mounted so as to protrude rearward in a side view of the vehicle, the movable range of the front wheel 11 in front of the exhaust pipe 8L provided with the primary catalyst device 9A can be further secured.

  The left and right port exhaust pipes 8L and 8R are provided downstream of the primary catalyst device 9A with a collecting portion 81 that joins both the exhaust pipes 8L and 8R together. Since the tube bundle part integrally formed so as to bundle 8R is provided, the heat of the primary catalyst device 9A of the exhaust pipe 8L of the left port is transmitted to the exhaust pipe 8R of the right port, and the exhaust gas of the exhaust pipe 8R is transferred. Since it can be heated in advance, the purification of the exhaust gas in the secondary catalyst device 9B in the collecting portion 81 can be promoted.

Although one embodiment of the present invention has been described above, the aspect of the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention includes those implemented in various aspects within the scope of the gist of the present invention.
For example, the straddle-type vehicle of the present invention is not limited to the motorcycle according to the embodiment, but includes small three-wheel and four-wheel buggy cars, and the internal combustion engine may be any type of air cooling, water cooling, and the number of cylinders.
The plurality of exhaust pipes are a plurality of exhaust pipes that are respectively connected to a plurality of (two) exhaust ports provided for the same bore when the internal combustion engine is a single cylinder unlike the present embodiment. Moreover, the effect of the said embodiment can be show | played similarly.
Moreover, although the arrangement | positioning on either side of each apparatus was specifically described and illustrated to the thing of illustration for convenience of explanation, the thing of the arrangement | positioning left-right reverse to what is shown to the said embodiment is also contained in this invention.

DESCRIPTION OF SYMBOLS 1 ... Motorcycle ("saddle-type vehicle" of this invention), 3 ... Internal combustion engine, 4 ... Oil filter, 5 ... Transmission, 8L ... Exhaust pipe (of left port), 8La ... Bending part, 8R ... ( Exhaust pipe (at right port), 9A ... primary catalyst device, 9B ... secondary catalyst device, 11 ... front wheel, 20 ... head pipe, 21 ... main frame, 22 ... center frame, 23 ... down tube, 23a ... lower end, 24 ... Lower frame, 24b ... Branch part, 25 ... Seat stay, 26 ... Pivot part, 30 ... Crankcase, 31 ... Crankshaft, 33 ... Cylinder block, 34 ... Cylinder head, 36 ... Intake port, 37 ... Exhaust port, 38 ... O ₂ sensor, 51 ... output sprocket 80 ... muffler, 81 ... collective unit, 82 ... tube bundle unit

Claims (7)

An internal combustion engine (3) is supported on the body frame (2), and a front wheel (11) is disposed in front of the internal combustion engine (3).
A plurality of exhaust pipes (8L, 8R) are connected to the front portion of the internal combustion engine (3), and the primary catalyst device (9A) and its downstream side are located in the middle of the exhaust paths of the plurality of exhaust pipes (8L, 8R). In the exhaust device of the saddle-ride type vehicle (1) that accommodates the secondary catalyst device (9B),
The primary catalyst device (9A) includes the front wheels (8L, 8R) in front of the crankcase (30) of the internal combustion engine (3) in a part of the exhaust pipes (8L, 8R). 11) An exhaust system for a saddle-ride type vehicle, which is disposed behind the vehicle in the vehicle width direction.   The plurality of exhaust pipes (8L, 8R) are connected to a muffler (80) arranged on one side in the vehicle width direction and have a longer path among the plurality of exhaust pipes (8L, 8R) ( The exhaust device for a saddle-ride type vehicle according to claim 1, wherein the primary catalyst device (9A) is accommodated in 8L).   The vehicle body frame (2) has a down tube (23) descending from the head pipe (20) to the lower rear part, and bifurcated from the lower end (23a) of the down tube (23) to the rear of the vehicle. 3. The lower catalyst frame according to claim 1 or 2, further comprising a lower frame (24) toward the front, wherein the primary catalyst device (9A) is disposed between the left and right lower frames (24) in a vehicle front view. The exhaust system of the saddle riding type vehicle as described.   An oil filter (4) is attached to the front and bottom of the internal combustion engine (3), and the primary catalyst device (9A) and the oil filter (4) are arranged so as to overlap each other when viewed from the front of the vehicle. The exhaust device for a saddle-ride type vehicle according to claim 3. The exhaust system for a saddle-ride type vehicle according to claim 4, wherein the primary catalyst device (9A) is disposed in front of the lower frame (24) in a side view of the vehicle . Among the plurality of exhaust pipes (8L, 8R), the exhaust pipe (8L) including the primary catalyst device (9A) includes a connection portion (37) to the internal combustion engine (3) and the primary catalyst device (9A). The O ₂ sensor (38) is disposed between the O ₂ sensors (38), and the O ₂ sensor (38) is attached to protrude rearward in a side view of the vehicle. The exhaust system of the saddle riding type vehicle as described. The plurality of exhaust pipes (8L, 8R) are provided downstream of the primary catalyst device (9A) with a collection part (81) for collectively joining the plurality of exhaust pipes (8L, 8R). A tube bundle portion (82) integrally formed so as to bundle the plurality of exhaust pipes (8L, 8R) on the upstream side over (81);
The exhaust device for a saddle-ride type vehicle according to any one of claims 1 to 6, wherein the secondary catalyst device (9B) is disposed in the collecting portion (81).

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