JPH03266788A - Motorcycle - Google Patents

Abstract

PURPOSE:To make it easy to arrange exhaust pipes by pivotally attaching the upper end of a rear wheel buffer to a cross member provided above the rear fork pivotally attached portion of main pipes, and extending one of exhaust pipes between the pivotally attached portion and the rear end of one main pipe, and extending the other exhaust pipe beneath a rear frame. CONSTITUTION:A cross member 16 is horizontally installed above the rear fork pivotally attaching point 27a of main pipes 4a, 4b and the upper end of a rear wheel buffer 30 is attached to the cross member 16 and set in the vertical direction. The exhaust pipes 39, 40 of front cylinders 36, 37 are curved rearward while being extended downward and are extended along the lower face of an engine 35 and the chambers 39b, 40b of the exhaust pipes 39, 40 are located near the center of both side portions of a rear wheel 28. The exhaust pipe 41a of the rear cylinder 38 is curved when wound around the side of the rear wheel buffer 30 and is extended along a rear frame 11 from between the main pipes 4a, 4b. By this constitution the sudden curve of each exhaust pipe is removed so that the exhaust efficiency of a motorcycle is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a motorcycle in which an exhaust system can be effectively installed.

(Prior Art) Generally, the body frame of a motorcycle is composed of a pair of left and right frames in order to mount an engine, a fuel tank, a seat, etc., and to ensure strength.

For example, in the motorcycle shown in Japanese Utility Model Publication No. 52-53098, various auxiliary devices are built into the vehicle body, and the rear suspensions 15 and 15 are arranged in two groups on the left and right when viewed from the rear (FIG. 3).

(Problem to be solved by the invention) By the way, in high-performance motorcycles such as race cars, in order to increase exhaust efficiency and ensure maximum engine output, the exhaust system connected to the cylinder is made as straight as possible. Therefore, the layout of the exhaust system is an extremely important requirement.

However, in the motorcycle of Utility Model Publication No. 52-53098 mentioned above, the exhaust pipe bypasses the outside of the rear suspension while avoiding interference with the left and right frames, and the exhaust pipe only occupies a large amount of the rear side of the vehicle body. First, the exhaust pipe itself has a shape with a large bend, and there are disadvantages such as not being able to maximize engine output.

(Means and effects for solving the problem) In order to solve the problem, the present invention extends a pair of left and right main pipes diagonally downward from the head tube, and the engine is arranged below these main pipes. In addition, in a motorcycle in which a rear fork is pivotally attached to the rear part of the main pipe, a rear frame is extended rearward from the rear part of the main pipe, and a seat is supported by this rear frame, the rear fork pivot of the main pipe is provided. A cross member is horizontally extended above the mounting part, and the upper part of a rear wheel shock absorber is pivotally connected to the middle part of the cross member, and at the same time as the rear wheel shock absorber is lowered, at least one A main exhaust pipe is made to pass near the rear wheel shock absorber and between the rear part of the main pipe, and further, at least one exhaust pipe is made to extend below the rear frame. .

(Example) Hereinafter, preferred examples that further embody the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing an outline of a motorcycle according to the present invention;
Fig. 2 is a side view of the same, Fig. 3 is a plan view of the vehicle body frame according to the present invention, Fig. 4 is a side view of the same, Fig. 5 is a front view of the same (only the down tube is shown), and Fig. 6 is a rear view of the same. It is a diagram.

A motorcycle designated by the reference numeral 1 as shown in FIGS. 1 and 2 has a body frame 2, and this body frame 2 has a head tube 3 disposed in the front part as shown in FIGS. 3 to 6. A main pipe 4a is provided and extends rearward from the rear upper part of the tube 3.

4b, a down tube lower 5, 5 whose rear parts 4c, 4d are curved and extended forward; a down tube 6.6 whose tip is bent and extended upward and connected to the lower part of the herad tube 3; 6.6 A sub tube 7.7 connecting the middle part and the middle part of the main pipes 4a, 4b, upper vibes 8a, 8b extending rearward from the middle part of the main pipes 4a, 4b, and an upper vibe 8 on the left side.
The rear part of a and the rear curved part of the left main pipe 4a are connected by a linear sub-vibe 9, and the upper part of the middle part of the rear part of the right upper vibe 8b and the rear curved part of the right main pipe 4b forms a mountain. They are connected by a sub-vibrator 10 that is slightly bent. These upper vibes 8a, 8b
The sub-vibs 9 and 10 constitute a rear frame 11 that supports the seat 34. Note that the joining position of the sub-vibe 10 to the right upper vibe 8b is slightly forward of the joining position of the sub-vibe 9 to the left-side upper vibe 8a, and as a result, the sub-vibe 10 is
When viewed from the side as shown in Figure S4, they are located entirely above, and there is a gap S between them. Also, the sub-vibrator 1 on the right
The middle part of the upper vibe 8a on the right side and the middle part of the upper vibe 8a on the right side are connected by a sub tube 12. In this way, the left and right pair of sub-vibes 9 and 10 are configured asymmetrically, and the reason for this is that an exhaust device from the rear cylinder is disposed below the right sub-vibe 10, as will be described later.

In addition, there are cross members 13, 14 between each left and right vibrator,
15.18, also cross plate 17°18, 19.2
0 is installed at each required position, and a U-shaped grip 21 is fixed to the rear side of the left upper vibe 8b.

Then, returning to FIGS. 1 and 2, the vehicle body frame 2
A front fork 22 is pivotally attached to the Herad tube 3 of R1 via both top and bottom bridges 23 and 24, the front fork 22 supports a front wheel 25 at its lower part, and a handle 26 is attached to its upper part.

On the other hand, the curved rear portions 4c, 4 of the main pipes 4a, 4b
A pivot part 27a for the rear fork 27 is provided at the rear fork part 27a, and the rear fork 27 is pivotally attached to the rear fork pivot part 27a. The front part of the fork 27 supports the lower end of the rear wheel shock absorber 30 via the progressive link mechanism 29, and the upper end of the rear wheel shock absorber 30 is supported by a bracket 31 provided at the middle part of the cross member 16. As a result, the rear fork 27 is supported by a progressive link type rear wheel M shock device 32 interposed between the rear fork 27 and the vehicle body frame. In both types, one rear wheel shock absorber 30 is disposed vertically at the center in the vehicle width direction.

Further, a fuel tank 33 is attached to the main pipes 4a, 4b, and a seat 34 is attached to the rear frame 11, which is made up of upper vibes 8a, 8b and sub-vibes 9, 10.

On the other hand, as shown in FIG. 2, a side V-type engine 35 with two cylinders in the front and one cylinder in the rear is mounted on the down tube lower 5.5. This engine 35 includes a pair of left and right cylinders 36 and 37 at the front, and one cylinder 38 at a position intermediate between the cylinders 36 and 37 at the rear.

In this engine 35, first, the front left and right pair of cylinders 36 and 37 are inclined at an angle close to the front horizontal direction, and the left and right pair of exhaust devices 39 and 40 extend from the lower side of each cylinder 36 and 37. Extend to the rear. Specifically, the front exhaust pipes 39a and 40g connected to each cylinder are extended downward and curved rearward, so that the front exhaust pipes 39a and 40g are curved rearward to follow the lower surface of the engine 35, and a chamber is integrally communicated with the rear part of the front exhaust pipes 39a and 40a. 39b and 40b are respectively located near the middle of both measuring parts of the rear wheel 28, furthermore, silencers 39c and 40c are arranged which communicate integrally with the rear ends of the chambers 39b and 40b,
The rear end of this muffler 39C3400 is arranged so as to be substantially aligned with the rear end of the vehicle body frame 2.

On the other hand, the rear cylinder 38 is similar to the front cylinder 36.37.
The exhaust device 41 is inclined rearward at an angle nearly perpendicular to the rear circumferential side, and the exhaust device 41 is provided rearwardly from the rear peripheral side. Since the cylinder 38 is located at the center in the vehicle width direction, the front exhaust pipe 41a connected to the cylinder 38 is arranged substantially horizontally at the rear. Since the rear wheel shock absorber 30 is present behind the cylinder 38, the front exhaust pipe 41a extends from one side of the rear wheel N1aj device 30, that is, the left side in the embodiment, to the other side, that is, the right side. Curve it so that it wraps around the area and reach the rear.

As is clear from FIG. 1, the front exhaust pipe 41a bypasses the rear wheel shock absorber 30 when viewed from the plane. As shown in the figure, the rear end of the curved front exhaust pipe 41a reaches the right side of the vehicle body, but since the sub-vibrator 10 on the right side of the vehicle body frame 2 is provided at a relatively higher position than that on the left side, the rear end of the front exhaust pipe 41a is curved as shown in the figure. A chamber 41b integrally connected to the end thereof is disposed below the sub-vibe 10 as shown in FIG.
A muffler 41c is connected to the rear end of the muffler 41c.

Therefore, the front exhaust pipe 41a of the exhaust device 41 provided in the rear cylinder 3B utilizes the installation space of the rear wheel A component 30 supported by the progress printer mechanism 29, and is curved to wind it. Since the exhaust devices 39,40. and 41 can be substantially aligned.

Furthermore, since the pair of left and right sub-vibrators 9 and 10 are configured asymmetrically, a space for disposing the exhaust device 41 can be effectively secured.

By the way, in principle it is fine to set either sub-vibe 9 or 10 higher, but as mentioned above, the left upper vibe 8
Since the grip 21 is fixedly installed on the part b, it is desirable to raise the sub-vibrator 10 on the right side of the vehicle body. The reference numeral 42 in the figure is a head vibe gusset.

It should be noted that the present invention allows arbitrary changes in the embodiments, such as the shape of details, etc., without departing from the gist of the invention.

(Effects of the Invention) As described above, the present invention allows one exhaust pipe to pass between the left and right main pipes and near the fallen rear wheel halide. The exhaust pipes of high-performance motorcycles such as cars can be easily arranged. In other words, the sharp bend in the exhaust pipe found in conventional motorcycles has been eliminated, and the exhaust pipe can now extend in a nearly straight line, reducing exhaust resistance and improving engine output. I can do it.

Furthermore, since the exhaust pipe is passed between the main pipes, an excellent vehicle body layout can be obtained, such as even if the exhaust pipe is placed close to under the seat, it will not be touched from the outside.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an outline of a motorcycle according to the present invention;
Fig. 2 is a side view of the same, Fig. 3 is a plan view of the vehicle body frame according to the present invention, Fig. 4 is a side view of the same, Fig. 5 is a front view of the same (only the down tube is shown), and Fig. 6 is a rear view of the same. figure. In the drawings, 1 is a motorcycle, 4a and 4b are main pipes, 4c and 4d are rear parts of the main pipes, 11 is a rear frame, 16 is a cross member, 27 is a rear fork, and 27a
30 is a rear wheel shock absorber, 34 is a seat, 35 is an engine, and 41a is an exhaust pipe. Figure 6

Claims (1)

[Claims] A pair of left and right main pipes extends diagonally downward rearward from the head tube, an engine is disposed below these main pipes, and a rear fork is pivotally attached to the rear part of the main pipes. In a motorcycle in which a rear frame is extended rearward from the rear of the pipe and the seat is supported by this rear frame, a cross member is horizontally extended above the rear fork pivot portion of the main pipe, and the cross member is An upper part of a rear wheel shock absorber is pivotally attached to the intermediate portion, and the rear wheel shock absorber is lowered, and at least one of the rear wheel shock absorbers extends from the engine.
A main exhaust pipe is made to pass near the rear wheel shock absorber and between the rear part of the main pipe, and further, at least one exhaust pipe is made to extend below the rear frame. Motorcycle.