JP4730244B2 - Intake device for motorcycle - Google Patents

Description

  The present invention relates to a motorcycle intake device in which a resonator chamber for reducing intake noise is provided in an air cleaner.

  In recent years, fuel injection systems have become widespread as fuel supply devices for motorcycles, replacing conventional carburetor systems. In a fuel injection type fuel supply device, a throttle body is connected between an engine and an air cleaner, and a butterfly valve built in the throttle body is appropriately opened to take in air from an intake device (air cleaner). In addition, an amount of fuel corresponding to the amount of intake air is injected from a fuel injection valve (injector) provided in the throttle body toward the intake port or the like, and a fuel mixture having an appropriate air-fuel ratio is always supplied to the engine.

  Further, when the engine is idling, since the butterfly valve of the throttle body is closed, air is sucked from the bypass passage that bypasses the butterfly valve. An ISC (idle speed control) valve using a solenoid valve or the like is interposed in the bypass passage. By controlling the opening and closing of the ISC valve, an air amount necessary for idling operation is secured.

  As a drawback of such a fuel supply device equipped with a solenoid valve type ISC valve, when the intake negative pressure pulsation coincides with the opening timing of the ISC valve during idling operation, an intake noise of “pocopoco” is generated from the IPS valve. The intake noise is radiated to the outside from the intake port of the intake device (air cleaner), which may cause a problem as annoying noise.

In the prior art, as described in Patent Documents 1 to 3, a chamber-like resonator chamber (resonance chamber) is provided between the air cleaner itself or the air cleaner and the throttle body, and the shape of the resonator chamber and By appropriately setting the volume, a resonance action is caused to cancel out and reduce the intake sound from the ISC valve.
Japanese Patent No. 2670079 Japanese Utility Model Publication No. 63-177656 Japanese Patent No. 2854277

  However, in the air intake device of Patent Document 1, since the resonator chamber is disposed between the air cleaner and other peripheral devices (fuel tank or top cover), there is no sufficient space around the air cleaner. Cannot be adopted. If a resonator chamber is separately provided even though there is not enough space around the air cleaner, the capacity of the air cleaner is reduced and the intake charging efficiency is lowered.

  Further, in the air intake device of Patent Document 2, a resonator chamber is disposed on the downstream side (clean side) with respect to the cleaner element inside the air cleaner. However, it is originally effective to provide a resonator chamber in the air intake passage that is the most upstream part of the air cleaner and the intake air is throttled and the flow velocity is increased. Since a resonator room is provided, the intake noise reduction effect is low.

  Furthermore, in the air intake device of Patent Document 3, a resonator plate is formed by adhering a lid plate to an air cleaner cap, and this resonator chamber is opened to a position where air from the air intake of the air cleaner does not flow directly into the resonator chamber. I am letting. However, since the opening of the resonator chamber is not provided at a position where all the intake air passes, the effect of reducing the intake noise is low.

  The present invention has been made in view of such matters, and it is possible to install a resonator chamber inside the cleaner case without sacrificing the capacity of the air cleaner or increasing the size of the cleaner case, thereby effectively reducing intake noise. Motorcycles that can easily reduce the replacement of the resonator chamber and cleaner element and change the shape of the resonator chamber, improve rigidity around the resonator chamber, and prevent water and foreign matter from entering the resonator chamber. An object is to provide an air intake device.

In order to achieve the above object, the fuel intake device for a motorcycle according to the present invention divides the interior space of the cleaner case into a dirty side and a clean side by a cleaner element, and a separate resonator chamber is arranged in the dirty side. In the motorcycle intake device in which the resonator chamber communicates with an air intake passage for taking outside air into the dirty side from the outside , the cleaner case is formed so as to be divided in the vehicle width direction of the motorcycle. The element has a plate shape and is arranged approximately parallel to the center plane of the vehicle. The dirty side is arranged on the outermost side in the vehicle width direction with respect to the cleaner element, and the resonator chamber can be attached to and detached from the dirty side. And the air intake passage from the outside to the cleaner element. The tube is formed into a tubular shape that enters into the cleaner case, and a branch pipe that branches in a substantially T-shape is provided in the entry section of the air intake passage into the cleaner case, while the resonator chamber is substantially L-shaped. The connecting portion is formed at one end thereof, the volume chamber is formed at the other end side, and the connecting portion is connected to the branch pipe of the air intake passage so that the volume chamber is substantially parallel to the cleaner element . It is characterized by that.

  In the motorcycle fuel intake device according to the present invention, the connecting portion of the resonator chamber is detachably fitted and connected to the branch pipe of the air intake passage, and the volume chamber of the resonator chamber is connected to the dirty side. The cleaner case constituting member to be formed is detachably fixed to the inner side surface by at least one fastening portion.

  Further, the fuel intake device for a motorcycle according to the present invention is characterized in that the resonator chamber is connected to the lower side of the air intake passage, and a drain hole for draining water is formed in the lowest portion of the resonator chamber. To do.

  Furthermore, the motorcycle fuel intake system according to the present invention is characterized in that the resonator chamber is connected to the upper side of the air intake passage.

  According to the motorcycle air intake apparatus of the present invention, the resonator chamber is connected to the air intake passage that connects the air cleaner chamber and the outside, so that intake noise propagating from the air cleaner chamber to the outside is reliably reduced. be able to. In addition, since the resonator chamber is provided in the air cleaner chamber, the capacity of the cleaner case can be secured while avoiding interference with peripheral components. Further, the resonator chamber and the cleaner element can be easily replaced and the shape of the resonator chamber can be easily changed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a left side view of a body frame, an engine, a fuel tank, a fuel supply device, an intake device, etc. of a motorcycle to which an intake device according to the present invention is applied, FIG. 2 is a right side view, and FIG. It is a top view by the III arrow of FIG.

  The body frame 2 of the motorcycle 1 includes a head pipe 3, an upper pipe 4, a lower pipe 5, a pair of left and right center pipes 6, a pair of left and right seat pipes 7 and a seat stay 8, and reinforcing pipes 9, 10 and a number. It is configured with a bridge pipe 11 etc. of the book. An engine 15 is fixed to engine suspension brackets 12, 13, and 14 provided near the lower end of the lower pipe 5 and the middle and lower ends of the center pipe 6. The engine 15 firmly connects the lower pipe 5 and the center pipe 6, and the engine 15 itself also serves as a structural member of the vehicle body frame 2.

  The engine 15 is, for example, a single-cylinder four-cycle air-cooled engine, and a cylinder assembly 17 is installed on the upper surface of the engine case 16 so as to tilt forward. The cylinder assembly 17 has a configuration in which a cylinder block 18, a cylinder head 19, and a head cover 20 are placed on the engine case 16 in this order.

  A front fork that supports a front wheel (not shown) is supported on the head pipe 3 so as to be steerable to the left and right together with a handlebar and the like, and a swing arm that supports a rear wheel (not shown) is provided on an engine suspension bracket 13 provided at an intermediate portion of the center pipe 6. The base part is fastened together with the engine 15 by the engine fixing bolt 23, and the swing arm is supported so as to be swingable up and down.

  A cushion bracket 25 is fixed to the rear end of the upper pipe 4, and an upper end of the rear cushion unit 26 is rotatably connected to the pivot shaft 27. The lower end of the rear cushion unit 26 is connected to the swing arm via a link mechanism (not shown) or the like. Further, a side stand bracket 29 is provided in the vicinity of the joint between the left center pipe 6 and the seat stay 8, and a side stand for parking (not shown) is assembled thereto.

  A fuel tank 31 is laid over the upper pipe 4, and a seating seat (not shown) is placed behind the fuel tank 31 and above the seat pipe 7. Further, an air cleaner 33 that is a main part of the air intake device 32 according to the present invention is provided in a substantially triangular space surrounded by the center pipe 6, the seat pipe 7, and the seat stay 8.

  An intake port 35 is provided at the rear part of the cylinder head 19 of the engine 15, and a tubular throttle body 36 is connected to the intake port 35. An intake pipe 37 protruding forward from the front of the air cleaner 33 is provided at the rear part of the throttle body 36. Connected. The member 38 is a composite type in which a throttle position sensor for detecting the throttle opening, an intake pressure sensor for detecting the intake pressure of the intake passage in the throttle body 36, and an intake air temperature sensor for detecting the intake temperature of the intake passage are integrated. The member 39 is an ISC (idle speed control) valve that adjusts the intake air amount during idling operation, as will be described in detail later. In addition, an air intake passage 41 for sucking outside air is provided on the left side surface of the air cleaner 33.

  The throttle body 36 is provided with a discharge pump type fuel injection device 46. In this fuel injection device 46, a plunger type fuel pump driven by an electromagnetic valve, a fuel injection valve, and a pressure regulator for adjusting fuel pressure are integrated. The fuel injection device 46 is provided in the throttle body 36 in a backward inclined posture, and the fuel injection direction is directed to the inside of the intake port 35.

  On the other hand, an exhaust port 48 is provided at the front of the cylinder head 19, and an exhaust pipe 49 is connected to the exhaust port 48. The exhaust pipe 49 is curved so as to extend forward from the exhaust port 48 and then U-turn rightward. The exhaust pipe 49 extends rearward through the upper right side of the engine case 16 and is connected to an exhaust muffler (not shown). The reason why the exhaust pipe 49 is biased to the right side of the vehicle body is that the rider usually gets on and off from the left side of the motorcycle and pushes it, so that the exhaust muffler that gets hot does not cause the heat damage to the rider. It is to make it.

  On the other hand, a fuel outlet 54 is provided at the bottom of the fuel tank 31 located above the fuel injection device 46, and a vapor inlet 55 is provided in the fuel tank 31 and at a position sufficiently higher than the fuel outlet 54. . The vapor inlet 55 is formed in a strainer shape, for example. A fuel hose 57 is connected to the fuel outlet 54, and the other end is connected to the rear upper part of the fuel filter 58 fixed to the right front portion of the air cleaner 33, for example. A fuel hose 59 extending from the front surface of the fuel filter 58 is connected to the fuel injection device 46.

A return hose 61 extending from the top of the fuel injection device 46 is connected to the return hose 63 via the trifurcated branch 62, and the other end of the return hose 63 is connected to the vapor inlet 55 of the fuel tank 31. Further, another return hose 64 extends from the trifurcated branch 62 and is connected to the fuel filter 58.

  As shown in a schematic configuration diagram in FIG. 4, a fuel supply device 70 includes a throttle body 36, a fuel injection device 46, an ECU 66, and the like. The throttle body 36 is provided with a bypass passage 71 for bypassing the upstream and downstream intake passages, and the aforementioned ISC valve 39 is interposed in the bypass passage 71. The ISC valve 39 is, for example, a solenoid valve. Further, the above-described composite sensor 38 provided in the throttle body 36 detects the opening degree of the throttle valve 73, the intake pressure in the intake passage in the throttle body 36, and the intake air temperature. Further, the engine 15 is provided with an engine rotation speed sensor 73. The ISC valve 39 and the fuel injection device 46 are controlled by the ECU 66.

  The fuel in the fuel tank 31 flows through the fuel outlet 54 → the fuel hose 57 → the fuel filter 58 → the fuel hose 59 and is supplied to the fuel injection device 46. Further, vapor (bubbles) generated when the fuel is pressurized in the fuel pump unit inside the fuel injection device 46 flows from the vapor inlet 55 to the fuel tank through the return hose 61 → the three-branch branch 62 → the return hose 63. Released in 31. Further, the surplus fuel in the fuel injection device 46 flows in the order of return hose 61 → trifurcated branch 62 → return hose 64 → fuel filter 58 → fuel hose 59 and is supplied to the fuel injection device 46 again.

  The ECU 66 sets a fuel injection map set in advance based on information on the throttle opening, intake pressure and intake air temperature input from the composite sensor 38 and information on the engine speed input from the engine speed sensor 73. Accordingly, the fuel is injected into the fuel injection device 46. Further, the ECU 66 opens the ISC valve 39 when the throttle opening is zero (the throttle operation amount is zero), and the engine 15 supplies the air from the bypass passage 71 for the idling operation. In this case, an optimal amount of fuel is injected into the fuel injection device 46. Further, the ECU 66 stops the fuel injection from the fuel injection device 46 and reduces the fuel consumption rate when the throttle opening becomes zero while the motorcycle 1 is traveling (when the engine brake is used).

  The air cleaner 33 is biased to one side in the vehicle width direction, for example, the left side, and is fixed to the vehicle body frame 2. ing. In addition, a rear cushion unit 26 is arranged in parallel to the vehicle center plane C on the inner side (right side) of the air cleaner 33 in the vehicle width direction. is doing.

  6 is a left side view of the air cleaner 33, and FIG. 7 is a plan view of the air cleaner as viewed in the direction of arrow VII in FIG. The air cleaner 33 includes a resin cleaner case 76. The cleaner case 76 includes a case body 77 located on the inner side (right side) in the vehicle width direction, and a case cap 78 located on the outer side (left side) in the vehicle width direction. Is a configuration that can be divided in the vehicle width direction. Further, a separate element cap 79 is provided on the left side surface of the case cap 78 by means of four screws 80 so as to be separable (detachable) in the vehicle width direction. The element cap 79 is formed with a bulging portion 81 that bulges outward (left side) in the vehicle width direction.

  A filter fixing portion 83 for fixing the fuel filter 58 is integrally formed at the upper right of the front portion of the case body 77, and a fixing bracket 84 for fixing the entire air cleaner 33 to the vehicle body frame 2 around the upper surface of the case body 77. , 85 are integrally molded. As shown in FIGS. 3 and 7, the cleaner case 76 is formed in a substantially L shape in plan view, and includes a stepped portion 86 that avoids the rear cushion unit 26. As shown in FIG. 2, a recess 87 that avoids the exhaust pipe 49 is formed in the lower portion of the cleaner case 76. Reference numeral 88 denotes a breather union for connecting the breather hose 89 of the engine 15 shown in FIGS.

  As shown in FIGS. 6 and 7, at the joint between the case cap 78 and the element cap 79, a cleaner element 90 formed in a plate shape from a filterable material such as sponge is formed with respect to the vehicle center plane C. With the cleaner element 90 in between, the internal space of the cleaner case 76 is partitioned into a dirty side 91 on the outer side (left side) in the vehicle width direction and a clean side 92 on the inner side (right side) in the vehicle width direction. Yes. That is, the internal space of the element cap 79 (mainly the bulging portion 81) is the dirty side 91, and the internal space of the case body 77 and the case cap 78 is the clean side 92. The cleaner element 90 can be easily replaced by removing the element cap 79.

  As apparent from FIG. 7, the volume of the dirty side 91 is significantly smaller than the volume of the clean side 92. An intake pipe 37 connected to the throttle body 36 communicates with the clean side 92. On the other hand, the air intake passage 41 for taking in outside air passes through the rear wall 81a of the bulging portion 81 of the element cap 79 and communicates with the interior of the dirty side 91 substantially parallel to the cleaner element 90 and substantially horizontally. A part 81b (see FIG. 6) of the rear wall 81a of the bulging portion 81 is integrally provided in the air intake passage 41. A chamber-like resonator chamber 94 is provided in the dirty side 91.

  FIG. 8 is a right side view of the element cap 79, the air intake passage 41, and the resonator chamber 94 as viewed from the inner side in the vehicle width direction. FIG. 9 is a longitudinal sectional view of the air intake passage 41 and the resonator chamber 94. The air intake passage 41 is formed, for example, in a straight tube shape whose both ends are expanded in a funnel shape, and a branch pipe 95 is provided in the entry section of the air intake passage 41 into the cleaner case 76. The branch pipe 95 extends substantially vertically downward from a substantially middle portion of the entire length of the air intake passage 41 and branches into a substantially T shape.

  On the other hand, the resonator chamber 94 is completely separate from the air intake passage 41, is formed in a substantially L shape, and has a connecting portion 97 on one end side and a volume chamber 98 on the other end side. Then, the connecting portion 97 is removably fitted and connected to the branch pipe 95 of the air intake passage from the lower side in such a posture that the volume chamber 98 is below the air intake passage 41 and substantially parallel to the cleaner element 90. . Therefore, the resonator chamber 94 is disposed in the dirty side 91 as a separate chamber and is detachably connected to the air intake passage 41.

  Further, at least one fastening portion 99 is provided on the volume chamber 98 side of the resonator chamber 94, and the fastening portion 99 forms a dirty side 91 by a fastening member 100 such as a screw, for example, an element here. The cap 79 is detachably fastened to the inner wall surface. When only one fastening portion 99 is provided as in this embodiment, it is desirable to provide it at a position as far as possible from the connecting portion 97. A drain hole 101 for draining water is formed in the lowest part of the resonator chamber 94 (volume chamber 98). On the outer surface of the element cap 79, fitting bosses 102 for fitting side covers (not shown) are provided at three locations.

  In the intake device 32 (air cleaner 33) configured as described above, when the engine 15 is operated, outside air is taken into the dirty side 91 of the air cleaner 33 from the air intake passage 41 by the intake negative pressure of the engine 15, The outside air passes through the cleaner element 90 to remove foreign matters such as dust and then flows to the clean side 92 and is sucked into the engine 15 from the intake pipe 37 through the throttle body 36.

  When the engine 15 is idling, the throttle valve 73 of the throttle body 36 is closed, while the ISC valve 39 is opened and the bypass passage 71 is opened. Air necessary for idling operation is supplied to the engine 15 via the bypass passage 71. Is done. When the idling negative pressure pulsation of the engine 15 and the opening timing of the ISC valve 39 coincide with each other during the idling operation, an irritating intake sound is generated from the ISC valve 39. Although it tries to go outside from the passage 41, it is canceled by the resonance action of the resonator chamber 94 (volume chamber 98) provided in the air intake passage 41 and effectively silenced. The shape and volume of the resonator chamber 94 (volume chamber 98) are set to specifications that attenuate the intake sound of the ISC valve 39 most efficiently.

  The intake device 33 is provided with a completely independent resonator chamber 94 inside the air cleaner 33, so that it avoids interference with peripheral components (for example, the rear cushion unit 26, the exhaust pipe 49, the fuel filter 58, etc.). In addition, it is possible to improve the intake efficiency by securing the capacity of the air cleaner 33 to the maximum.

  In addition, the cleaner case 76 of the air cleaner 33 is formed so as to be divided in the vehicle width direction, the cleaner element 90 is formed in a plate shape, and is disposed substantially parallel to the vehicle center plane C, and the dirty side 91 is disposed in the cleaner element 90. Since the resonator chamber 94 is detachably disposed in the dirty side 91 by being disposed on the outermost side in the vehicle width direction, the cleaner case 76 is made compact in the vehicle width direction, and the cleaner element 90 and the resonator chamber 94 are Exchange can be facilitated.

  In addition, the shape of the resonator chamber 94 can be easily changed in accordance with the intake characteristics of the cleaner element 90, the frequency and volume of the intake sound generated by the ISC valve 39, and the like. In particular, the cleaner element 90 has various specifications as after-parts, which is effective when exchanging the resonator chamber 94 according to the specifications.

  To remove the resonator chamber 94, remove the element cap 79 from the cleaner case 76, remove the fastening member 100 fastened to the inner wall surface of the element cap 79 at the fastening portion 99 on the volume chamber 98 side, and further connect the resonator chamber 94. The resonator chamber 94 can be easily separated from the element cap 79 by removing the portion 97 from the branch pipe 95 of the air intake passage 41. With this mounting structure, the resonator chamber 94 can be fixed to the element cap 79 and the air intake passage 41 with high rigidity, and conversely, the attachment rigidity of the air intake passage 41 to the element cap 79 using the resonator chamber 94 Can be significantly improved. For this reason, there is no possibility that the resonator chamber 94 or the air intake passage 41 rattles in the cleaner case 76 and emits a vibration sound.

  Further, the air intake passage 41 is formed in a straight tube shape that is parallel to the vehicle center plane C like the cleaner element 90, and a branch pipe 95 that branches into a substantially T-shape is provided in the entry section into the cleaner case 76, The resonator chamber 94 is formed in a substantially L shape, a connecting portion 97 is formed on one end thereof, a volume chamber 98 is formed on the other end, and the connecting portion 97 is arranged so that the volume chamber 98 is substantially parallel to the cleaner element 90. Since it is connected to the branch pipe 95 of the air intake passage, the cleaner case 76, particularly the element cap 79 (the bulging portion 81) constituting the dirty side 91 can be made compact in the vehicle width direction. Moreover, since the volume chamber 98 is disposed so as to be substantially parallel to the air intake passage 41, the bulging portion 81 can be made compact in the height direction. Note that even if the volume of the dirty side 91 is smaller than that of the clean side 92, the intake efficiency is less likely to decrease.

  Since the resonator chamber 94 is disposed below the air intake passage 41, it is considered that foreign matter such as moisture and dust contained in the outside air taken in from the air intake passage 41 may enter the volume chamber 98. However, these foreign substances are effectively discharged from the drain hole 101 formed in the lowest part of the volume chamber 98.

  FIG. 5 is a schematic configuration diagram showing a modification in which the installation position of the resonator chamber in the cleaner case 76 of the air cleaner 33 is changed. In this figure, the components other than the intake pipe 103, the air intake passage 104, and the resonator chamber 105 are the same as those shown in FIG. Here, the resonator chamber 105 is provided so as to communicate with the intake pipe 103 instead of the air intake passage 104. Depending on the shape of the cleaner case 76, the intake sound of the ISC valve 39 can be similarly silenced by providing the resonator chamber 105 on the intake pipe 103 side in this way. Whether to take the form of FIG. 4 or FIG. 5 may be selected according to the configuration of the air cleaner and peripheral devices.

  FIG. 10 is a left side view of the air cleaner 33 showing a modification in which the positional relationship between the air intake passage 41 and the resonator chamber 94 shown in FIG. 6 is turned upside down. By connecting the resonator chamber 94 to the upper side of the air intake passage 41 in this way, it is possible to prevent foreign matters such as moisture and dust contained in the outside air taken in from the air intake passage 41 from entering the resonator chamber 94. Therefore, it is not necessary to provide the drain hole 101 shown in FIGS. 8 and 9 in the resonator chamber 94.

  In the present embodiment, the engine 15 is a single cylinder engine, but the configuration according to the present invention can be applied even to a motorcycle equipped with a multi-cylinder engine.

1 is a left side view of a body frame, an engine, a fuel tank, a fuel supply device, an intake device and the like of a motorcycle to which an intake device according to the present invention is applied. The right side view. The top view by the III arrow of FIG. The schematic block diagram of a fuel supply apparatus and an intake device. The schematic block diagram which shows the modification of an intake device. The left view of an air cleaner. The top view of the air cleaner by the VII arrow view of FIG. The right view which looked at the element cap, the air intake passage, and the resonator room from the vehicle width direction inner side. The longitudinal cross-sectional view of an air intake passage and a resonator room. FIG. 7 is a left side view of an air cleaner showing a modified example in which the positional relationship between the air intake passage and the resonator chamber shown in FIG. 6 is turned upside down.

Explanation of symbols

1 Motorcycle 2 Body frame
15 engine
32 Intake device
36 Throttle body
37 Intake pipe
39 ISC valve
41 Air intake passage
76 Cleaner case
77 Case body
78 Case cap
79 Element cap
90 Cleaner element
91 Dirty Side
92 Clean side
94 Resonator room
95 branch pipe
97 Connecting part
98 volume chamber
99 Fastening part
100 Fastening member
101 Drain hole C Vehicle center plane

Claims (4)

The internal space of the cleaner case is partitioned into a dirty side and a clean side by a cleaner element, a separate resonator chamber is provided in the dirty side, and the resonator is placed in the air intake passage that takes outside air into the dirty side from the outside. In a motorcycle intake system having a communication chamber, the cleaner case is formed so as to be split in the vehicle width direction of the motorcycle, and the cleaner element is formed in a plate shape and arranged substantially parallel to the vehicle center plane. The dirty side is disposed on the outermost side in the vehicle width direction with respect to the cleaner element, the resonator chamber is detachably disposed in the dirty side, and the air intake passage is substantially parallel to the cleaner element from the outside. Formed into a tubular shape that rushes into the cleaner case. A branch pipe that branches in a substantially T-shape is provided in the entry section of the passage into the cleaner case. On the other hand, the resonator chamber is formed in a substantially L-shape with a connecting portion at one end and a volume chamber at the other end. An intake device for a motorcycle, wherein the connection portion is connected to a branch pipe of an air intake passage so that the volume chamber is substantially parallel to the cleaner element . The connecting portion of the resonator chamber is detachably fitted and connected to the branch pipe of the air intake passage, and at least one volume chamber of the resonator chamber is provided on the inner surface of the cleaner case constituting member forming the dirty side. The motorcycle intake device according to claim 1, wherein the intake device is detachably fixed by a fastening portion . The intake device for a motorcycle according to claim 1 or 2 , wherein the resonator chamber is connected to a lower side of the air intake passage, and a drain hole for draining water is formed in the lowest portion of the resonator chamber. . The intake device for a motorcycle according to claim 1 or 2 , wherein the resonator chamber is connected to an upper side of the air intake passage .

Images