JPH046397Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an exhaust pipe device for a motorcycle.

(Prior art) In the exhaust pipe of a motorcycle, in an engine that is V-shaped in side view and has cylinders at the front and rear, the layout of the exhaust pipe for the front cylinder and the exhaust pipe for the rear cylinder is such that the front one hangs down and the rear cylinder exhaust pipe is placed at the rear. In addition, the rear part may be suspended, for example, by extending all the way to the rear, and the front part, or the rear part, or the left and right parts may be merged and guided to the muffler, or the front and rear parts may be connected to a collection chamber. They merge and lead to the muffler.

(Problem to be solved by the invention) In the above type, in which the front and rear exhaust pipes merge into the collecting chamber, the front part hangs down from the front cylinder and extends rearward to lead to the collecting chamber. The rear exhaust pipe is undesirable because it hangs down from the rear cylinder and has a chamber directly below it, resulting in a large difference in length between the front and rear exhaust pipes.

The present invention has been made to solve the above-mentioned technical problems, and its purpose is to provide an exhaust pipe device for a motorcycle that makes the lengths of the exhaust pipes of the front and rear cylinders substantially equal and is favorable in terms of engine performance.

(Means for solving the problems) The means for solving the above problems are as follows:
The first half of the exhaust pipe of the front cylinder is bent downward and in front of the cylinder, and the second half is extended rearward so as to face the bottom of the engine, and is connected to a collecting chamber arranged below or below the rear of the engine. At the same time, the first half of the exhaust pipe of the rear cylinder is bent and hangs downwardly behind the cylinder, and the second half is once bent forward and then changed direction toward the rear within a substantially plane plane;
The first half of the exhaust pipe of the front cylinder is connected in communication with the collecting chamber approximately parallel to the rear end thereof, and the collecting chamber is connected in communication with a muffler provided at the rear.

(Effects of the above means) According to the above means, the length of the exhaust pipe can be increased by bending the rear half of the exhaust pipe for the rear cylinder within a plane, and the lengths of the front and rear exhaust pipes can be made substantially equal.

(Embodiment) Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic side view of a motorcycle 1, which supports a front fork 5 which supports a front wheel 4 via a head tube 3 at the front end of a frame 2, and 6 is a handle. An engine 7 is mounted on the front lower part of the frame 2, a fuel tank 8 is mounted on the upper part, and a seat 10 is arranged on a seat rail 9 extending rearward from the middle part of the frame 2. A rear fork 12 supporting the rear wheel 11 is pivotably extended from the lower rear end of the rear fork 1.
A rear action unit 14 is interposed between the frame 2 and the frame 2 via a link mechanism 13.

The rear fork 12 is of an integral cantilever type, and the base 12a is bifurcated 12b, 12b, as shown in FIG. Middle part to rear part 12
c is formed of one piece, the rear axle 15 is rotatably horizontally supported on the end portion 12d, the rear wheel 11 is supported at one extending end 15a of the axle 15, and the other extending end 1
Attach and support the sprocket 16 to 5b, and connect the chain 1
7 to a drive sprocket 18 disposed on the side surface of a transmission case 701 at the rear lower part of the engine 7 to drive the rear wheels 11.

In this embodiment, the engine 7 is a four-cylinder water-cooled engine with two cylinders at the front and two cylinders at the rear, which is V-shaped when viewed from the side, and a carburetor 704 is disposed between the front and rear cylinders 702 and 703.

To explain the exhaust system, the exhaust pipes are as shown in FIGS. 3 and 4, and there are two front exhaust pipes 1 extending forward and downward from the left and right cylinder heads of the front cylinder 702.
The front parts 191, 201 of the engines 9, 20 are extended, and the rear parts 192, 202 of these are closely aligned and extended under the engine 7, and the rear ends 193, 203 are connected to the transmission case 701 of the engine 7. It is communicated and connected to connecting pipe portions 211 and 212 provided on the left half front surface of the collecting chamber 21 disposed on the left side of the lower rear or lower rear. By the way, as shown in FIG. 4, the left exhaust pipe 19 has its front half bent to the right, and bent to the left in an inverted V-shape a in plan view, so as to have approximately the same length as the right exhaust pipe 20. Two rear exhaust pipes 22 extend backward and downward from the left and right cylinder heads of the rear cylinder 703,
23 is hung down, the front half parts 221, 231 are hung down, and the rear parts 222, 223 are guided below the transmission case of the engine 7, and are opened forward and backward in a U-shape in plan view, and both sides are opened in substantially the same plane. The rear parts 223 and 233 are bent so as to substantially overlap each other, and have a substantially inverted L shape when viewed from the side, and the rear parts 223 and 233 are communicatively connected to the connection part 213 on the front right half of the collection chamber 21 described above. Therefore, the rear exhaust pipes 22 and 23 have an appearance similar to that of a coiled snake. In this way, the length of the rear exhaust pipes 22, 23 is increased, and the bent portions face the lower part of the rear of the engine, so that they do not interfere with the rear link mechanism 13.

An exhaust outlet pipe 214 is provided at the rear of the collecting chamber 21.
is integrally extended, and a joint 2 is attached to the rear end of this.
4. Fit the front end 27a of the exhaust guide pipe 27 of the muffler 26 through the packing 25, and attach the L-shaped band 2.
8 and hold and tighten. In the embodiment, the exhaust guide pipe 27 has a front portion 27b in plan view as shown in FIGS. 3 and 4.
is bent into an inverted L shape, faces in front of the tire of the rear wheel 11, extends outward across the tire on the opposite side from the drive mechanism, and slopes the rear part 27c rearward and upward. Connect muffler 26 and muffler 2
6 is located close to the middle or upper part of the side surface of the rear wheel 11 opposite to the drive mechanism 16, as shown in FIG.
The rear part 27c of the guide tube 27 faces the side of the tire,
In the embodiment, the band 28 is loosened to swing the muffler 26, and the muffler 26 is spaced apart from the outside of the rear wheel to facilitate removal of the rear wheel.

(Effect of the invention) As is clear from the above, according to the invention, the side view V
In this type of multi-cylinder engine, the exhaust pipe for the rear cylinder is bent so as to face the lower part of the rear part of the engine within a substantially plane plane, so that the length of the exhaust pipe can be increased to make it approximately the same length as the front exhaust pipe. , and the above can be planned without interfering with equipment or mechanisms disposed at the rear of the engine.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is a schematic side view of the motorcycle, Fig. 2 is a side view of the frame, Fig. 3 is a side view of the exhaust system, and Fig. 4 is a plan view of the same. , FIG. 5 is an exploded perspective view of the same. In addition, 1 in the drawing is a motorcycle, 7 is an engine, 1
9 and 20 are front exhaust pipes, 21 is a collecting chamber, 2
2 and 23 are rear exhaust pipes, and 26 is a muffler.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a motorcycle equipped with a V-type engine when viewed from the side, the front half of the exhaust pipe of the front cylinder is bent downward and in front of the cylinder, and the rear half is connected to the engine. facing downward and extending rearward, communicating and connecting to a collection chamber disposed at the lower rear of the engine or at the lower rear of the engine, and having the front half of the exhaust pipe of the rear cylinder bent and hanging downward to the rear of the cylinder; The rear half is once bent forward and then turned rearward within a substantially flat plane, and is connected to the collecting chamber approximately parallel to the rear end of the front half of the exhaust pipe of the front cylinder, and is connected to the collecting chamber. An exhaust pipe device for a motorcycle, characterized in that the exhaust pipe is connected to a muffler provided at the rear. (2) The latter part of the exhaust pipe for the rear cylinder faces the rear lower part of the engine.
2. Motorcycle exhaust pipe device.