JPH02130211A - Exhaust device for motor cycle - Google Patents

Abstract

PURPOSE:To make it possible to prevent an exhaust gas from oscillating, while enhancing the assembly ability of an exhaust pipe by arranging a support free intermediate section, vertically in the side part of a vehicle body, and by connecting adjacent exhaust pipes with the use of a coupling member. CONSTITUTION:Exhaust pipes 2 are held, in its intermediate section, in a support free condition, excepting their front and rear end parts 2f, 2e coupled to exhaust ports of an engine 1 and a muffler 3. The intermediate sections of the two exhaust pipes 2, 2 corresponding to the side part of a vehicle body are laid vertically, and accordingly, the width of the vehicle may be prevented from being increased. Further, the intermediate sections of the two exhaust pipes 2, 2 are coupled together with the use of a coupling member 6. With this arrangement, the exhaust pipes 2, 2 bind together so as to give a large rigidity as a whole of the exhaust pipe assembly. Accordingly, it is possible to prevent occurrence of oscillation even though the intermediate section is in a support free condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an exhaust system for a motorcycle equipped with a multi-cylinder engine.

[Prior art]

In motorcycles equipped with multi-cylinder engines, multiple exhaust pipes connect the engine exhaust port to a silencer installed at the rear of the vehicle body. Since the exhaust pipes connected in this way are extremely long,
If only the front and rear end portions are fixed, the intermediate portion will swing, causing problems such as interference with other parts such as the footrest during driving.

However, when the middle part of the exhaust pipe is supported and fixed to the vehicle body, the dimensional errors that inevitably occur during manufacturing make it difficult to assemble the exhaust pipe, and this poor assemblability reduces productivity. Put it away. Particularly, as in the case of a multi-cylinder engine, as the number of exhaust pipes increases, the assembly work becomes more complicated, which exacerbates this problem. In addition, if the middle part of the exhaust pipe is fixed with a support stay, the layout range of the footrest and brake lever placed in the middle of the exhaust pipe will be restricted, and the operating range of the brake lever will be restricted. There is also the problem of

[Problem to be solved by the invention]

The purpose of the present invention is to solve the above-mentioned conventional problems, improve the ease of assembling an exhaust pipe in a multi-cylinder engine, and prevent the exhaust pipe from swinging, and also to avoid restricting the layout of other parts. An object of the present invention is to provide an exhaust system for a motorcycle.

[Means to solve the problem]

To achieve the above object, the present invention provides a motorcycle in which at least two exhaust pipes per side are passed from the exhaust port of a multi-cylinder engine to the side of the vehicle body and connected to a muffler at the rear of the vehicle body. The exhaust pipes are made free of support between the connection to the engine exhaust port and the connection to the muffler, and the free support intermediate parts are placed vertically on the side of the vehicle body, and adjacent exhaust pipes are placed in a free-support state. This feature is characterized in that the two are connected by a hollow connecting member.

〔Example〕

Hereinafter, the present invention will be explained with reference to embodiments shown in the drawings.

Figure 1 shows a motorcycle equipped with the exhaust system of the present invention, where 1 is a parallel two-cylinder engine, 2 is an exhaust pipe provided for each cylinder of engine 1, and 3 is fixed to one side of the rear of the vehicle body. It's a silencer.

The two exhaust pipes 2, 2 each have a front end 2f connected to an engine exhaust port, pass through the side of the vehicle from one side of the vehicle, and connect a rear end 2e to the muffler 3. The intermediate portion is not fixed to the vehicle body by a support stay or the like and is in a free state. That is, each exhaust pipe 2 has a front and rear end 2f at the engine exhaust port and the muffler 3,
2e are simply connected, and the intermediate portion is free from support.

Reference numeral 4 denotes a footrest on which to place one's feet, which is located outside the exhaust pipes 2, 2, and a support arm that goes under the exhaust pipes 2, 2 and is fixed to the vehicle body frame. 5 is a brake lever arranged outside the footrest 4. Exhaust pipes 2 are installed before and after these footrests 4 and brake levers 5.
A protector 7.8 is arranged to cover the outside of the 2.degree. 9 is a tandem footrest.

As shown in detail in FIGS. 2 and 3, the two exhaust pipes 2, 2 are arranged one above the other in the middle portion corresponding to the side portion of the vehicle body, thereby preventing the width of the vehicle body from increasing. Further, the upper and lower exhaust pipes 2.2 are connected to each other at their intermediate portions by a connecting member 6. By connecting the connecting member 6, the exhaust pipes 2 and 2 restrain each other, and the exhaust pipe as a whole exhibits great rigidity, and even though the middle part is free of support, no vibration occurs. ing.

As shown in FIG. 4, the connecting member 6 has a hollow structure made by combining two metal plates in the middle, and this hollow structure connects the insides of the two exhaust pipes 2. I'm trying to communicate.

Furthermore, in the illustrated embodiment, the hollow cross-sectional area of the connecting member 6 is substantially the same as that of the exhaust pipe 2.

That is, the inner diameter Da of the connecting member 6 and the inner diameter De of the exhaust pipe 2
are substantially the same. With the two exhaust pipes 2.2 communicating with each other in this way, the pulsating waves from one exhaust pipe reach the other exhaust pipe, resulting in an increase in engine output due to the so-called pulsating effect. ing.

As described above, the exhaust system installed on the motorcycle simply connects the exhaust pipes 2, 2, which are arranged at least two per side of the vehicle body, to the engine exhaust port and the muffler 3 at the rear of the vehicle body. Since the intermediate portion is free from support, it is possible to easily assemble the engine exhaust port and the muffler by utilizing its appropriate flexure. In addition, since the middle part is free for support and no special support stay is provided between it and the vehicle body, the layout range of other parts such as the footrest and brake lever is restricted, or the operation range of the brake lever is restricted. Never.

In addition, since the two exhaust pipes are arranged one above the other on the side of the vehicle body, the vehicle body width does not need to be increased and the structure can be made compact.

In addition, even if the middle part of the exhaust pipe is left unsupported, the middle part is connected to each other by the connecting member, so
The mutual restraint of the exhaust pipes provides rigidity and prevents vibrations in the middle. Furthermore, since the connecting member has a hollow structure so that the insides of the exhaust pipes communicate with each other, the output of the engine can be improved by the pulsating effect of the exhaust pulsating waves.

〔Effect of the invention〕

As described above, the present invention allows at least two exhaust pipes per side to pass from the exhaust port of a multi-cylinder engine to the side of the vehicle body,
In a motorcycle configured to be connected to a silencer at the rear of the vehicle body, the at least two exhaust pipes are free from support between the connection to the engine exhaust port and the connection to the silencer, and the support is free. The intermediate parts are arranged vertically on the side of the vehicle body, and adjacent exhaust pipes are connected with a hollow connecting member, which improves the ease of assembling the exhaust pipe and prevents the exhaust pipe from swinging out. can do. Furthermore, there is no restriction on the layout or operation range of other parts.

Further, the width of the vehicle body can be made compact while providing a plurality of exhaust pipes.

[Brief explanation of the drawing]

Fig. 1 is a side view of a motorcycle equipped with the exhaust system of the present invention, Fig. 2 is a side view of the exhaust system disposed on one side of the body of the motorcycle, and Fig. 3 is a plan view of the exhaust system. , and FIG. 4 is an enlarged cross-sectional view of a connecting member portion at the intermediate portion of the exhaust pipe of the same exhaust system. 1... Engine, 2... Exhaust pipe, 3... Silencer,
6...Connecting member.

Claims (1)

[Claims] At least 2 per side from the exhaust port of a multi-cylinder engine
In a motorcycle in which an exhaust pipe is passed through the side of the vehicle body and connected to a silencer at the rear of the vehicle body, the at least two
The exhaust pipes of the main body are free from support between the connection to the engine exhaust port and the connection to the muffler, and the free support intermediate portions are arranged vertically on the side of the vehicle body, and the exhaust pipes are adjacent to each other. An exhaust system for a motorcycle that connects the two with a hollow connecting member.