JPH0567476B2 - - Google Patents

Description

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

(Prior Art) In general, a motorcycle has a pair of left and right main pipes extending obliquely downward from a head tube near the handlebar, and an engine is disposed below these main pipes.

For example, in the motorcycle shown in Japanese Patent Publication No. 56-63570, as is clear from Fig. 1, a suspension spring device S is interposed between the upper end of the engine E and the tip of the rear fork Rf. One end of the shock absorber 12 in S is pivotally connected to the upper end of the engine E, and extends rearward approximately horizontally.

(Problem to be Solved by the Invention) Several exhaust pipes extending from the engine E pass near the buffer 12.
Because the rear wheel Wr swings up and down a lot, the exhaust pipe is equipped with a shock absorber 1 to avoid interference.
It is necessary to place it sufficiently away from 2.

This causes problems such as the width of the vehicle body expanding near the shock absorber 12, and countermeasures are required.

(Means and effects for solving the problems) In order to meet the above requirements, the present invention provides a pair of left and right main pipes extending diagonally downward from the head tube, an engine disposed below these main pipes, and a main pipe. A rear fork is pivoted to the rear of the rear fork so that it can swing up and down, one rear wheel shock absorber is attached to this rear fork, and the upper part of this rear wheel shock absorber is pivoted to the main pipe at a position above the pivot point of the rear fork. In this type of motorcycle, the engine is a V-type engine in which the front cylinder and rear cylinder form a V-shape in side view, and a small-diameter front exhaust pipe, a larger-diameter chamber, and a silencer are connected in this order. The front exhaust pipes are all housed between the left and right main pipes in plan view, and the small-diameter front exhaust pipes extending from the rear cylinders are connected to the rear wheels. It is characterized by bypassing the upper part of the shock absorber and passing between the rear part of the main pipe.

Since there is only one rear wheel shock absorber, for example, if there are three front exhaust pipes, the two from the front cylinders only need to pass through both sides of the rear wheel shock absorber. The single front exhaust pipe from the rear cylinder may be routed around the upper part of the rear wheel shock absorber where the amount of vibration is small. Thereby, even if a plurality of front exhaust pipes are passed between the left and right main pipes, there is no need to increase the interval between the main pipes.

(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 the motorcycle according to the present invention, FIG. 2 is a side view of the same, FIG. 3 is a plan view of a body frame according to the present invention, FIG. 4 is a side view of the same, and FIG. 6 is a front view of the same (only the down tube is shown), and FIG. 6 is a rear view of the same.

The 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. Main pipes 4a, 4 extending rearward from the rear upper part of the tube 3
b, down tube blowers 5, 5 whose rear parts 4c, 4d are curved and extend forward; down tubes 6, 6 whose tips are bent and extended upward and connected to the lower part of the head tube 3;
6 subtubes 7, 7 connecting the intermediate part and the main pipes 4a, 4b intermediate parts, main pipes 4a, 4
Atsupa pipe 8 extending rearward from the middle part of b
a, 8b, and the left Atsupapipe 8a
The rear part of the right main pipe 4a and the rear curved part of the left main pipe 4a are connected by a straight sub-pipe 9, and the rear part of the right side pipe 8b and the rear curved part of the right main pipe 4b are connected so that the middle part thereof has a mountain on the upper side. They are connected by a slightly bent sub-pipe 10.
Note that the joining position of the sub pipe 10 to the right side Atsupah pipe 8b is slightly forward of the joining position of the sub pipe 9 to the left side Atsupah pipe 8a,
As a result, the subpipe 10 is located entirely above the subpipe 9 when viewed from the side as shown in FIG. 4, and there is a gap S between them. In addition, the middle part of the right sub-pipe 10 and the right side atsupapipe 8a
The intermediate portions of the tubes are connected by a subtube 12. In this way, the pair of left and right subpipes 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 subpipe 10, as will be described later.

In addition, there is a cross member 1 between each left and right pipe.
3, 14, 15, 16, and cross plate 1
7, 18, 19, and 20 are installed at respective required positions, and a U-shaped grip 21 is fixed to the rear side of the left upper pipe 8b.

Returning to FIGS. 1 and 2, a front fork 22 is pivotally attached to the head tube 3 at the front of the vehicle body frame 2 via top and bottom bridges 23 and 24, and this front fork 22 is attached to the front wheel at the bottom. 25, and a handle 26 is attached to the top.

On the other hand, a pivot portion 27 for a rear fork 27 is provided at the curved rear portions 4c, 4d of the main pipes 4a, 4b.
A rear fork 27 extending rearward is pivotally connected to this rear fork pivot portion 27a, and the rear fork 27 supports a rear wheel 28 at its rear end. The lower end of the rear wheel shock absorber 30 is supported, and the upper end of the rear wheel shock absorber 30 is supported by a bracket 31 provided at the intermediate portion of the cross member 16, and the rear fork 27 is interposed between this and the vehicle body frame. It is supported by a progressive link type rear wheel shock absorber 32. In addition, the rear wheel shock absorber 30
It is cylindrical and one piece is arranged vertically in the center of the vehicle width direction.

Further, a fuel tank 33 is provided on the main pipes 4a, 4b, and a seat 34 is provided on the top pipes 8a, 8b.

On the other hand, as shown in FIG.
A side V-type engine 35 with two cylinders in the front and one cylinder in the rear is mounted on top. 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, a pair of left and right cylinders 36 and 37 at the front are inclined at an angle close to the front horizontal. Extend to the rear. Specifically, the front exhaust pipes 39a and 40a connected to each cylinder are extended downward and curved rearward, so as to be aligned with the lower surface of the engine 35.
Chambers 39b and 40b, which communicate integrally with the rear portions of the front exhaust pipes 39a and 40a, are respectively located near the middle of both sides of the rear wheel 28.
muffler 39 integrally communicating with the rear ends of b and 40b
c, 40c are arranged, and these silencers 39c, 40c
The rear end is arranged to be approximately 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 3.
The exhaust device 41 is inclined rearward at an angle nearly perpendicular to 6 and 37, and an 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 located behind the cylinder 38, the front exhaust pipe 4
1a is curved so as to be wound from one side of the rear wheel shock absorber 30, that is, the left side in the embodiment, to the other side, that is, the right side, and extends to 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 right sub-pipe 10 of the vehicle body frame 2 is installed at a relatively higher position than the left side, A chamber 41b integrally connected to the end of the chamber 41b is disposed below the subpipe 10 as shown in FIG.
A muffler 41c is connected to the rear end of b.

Note that, as shown in FIG. 2, the front exhaust pipe 41a has a small diameter in order to pass through the upper side of the rear wheel shock absorber 30.

Therefore, the front exhaust pipe 41a of the exhaust device 41 provided in the rear cylinder 38 utilizes the installation space of the rear wheel shock absorber 30 supported by the progressive link mechanism 29, and curves it to wind it. Since the exhaust devices 39, 40, and 41 are extended to the front two cylinders, the equivalent pipe length can be made approximately equal to that of the exhaust devices 39 and 40 provided in the two front cylinders, and the distance in side view from the front end to the rear end can be shortened. The rear ends can be approximately aligned.

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

Incidentally, in principle, it is possible to make either the sub-pipe 9 or 10 higher, but as mentioned above, since the grip 21 is fixed to the upper pipe 8b on the left side, it is desirable to make the sub-pipe 10 on the right side of the vehicle body higher. The reference numeral 42 in the figure is a head pipe 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 includes attaching one rear wheel shock absorber to the rear fork, and pivoting the upper part of this rear wheel shock absorber to the main pipe at a position above the pivot joint of the rear fork. In this motorcycle, the engine is a V-type engine in which the front cylinder and the rear cylinder form a V-shape in side view, and the small-diameter front exhaust pipe extending from the rear cylinder is connected to the upper part of the rear wheel shock absorber. It is characterized by being detoured and passed between the rear part of the main pipe.

Since there is only one rear wheel shock absorber, for example, if there are three front exhaust pipes, the two from the front cylinders only need to pass through both sides of the rear wheel shock absorber. The single front exhaust pipe from the rear cylinder may be routed around the upper part of the rear wheel shock absorber where the amount of vibration is small.

The exhaust pipe from the rear cylinder is allowed to bend or meander in order to match the length of the exhaust pipe from the front cylinder. Therefore, the front exhaust pipe in the center was used as the exhaust pipe from the rear cylinder, bypassing the rear wheel shock absorber.

Thereby, even if a plurality of front exhaust pipes are passed between the left and right main pipes in plan view, there is no need to increase the interval between the main pipes. Therefore, the motorcycle can be made more compact.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an outline of the motorcycle according to the present invention, FIG. 2 is a side view of the same, FIG. 3 is a plan view of a body frame according to the present invention, FIG. 4 is a side view of the same, and FIG. 6 is a front view of the same (only the down tube is shown), and FIG. 6 is a rear view of the same. In the drawings, 1 is a motorcycle, 3 is a head tube, 4a, 4b are main pipes, 16 is a cross member, 27 is a rear fork, 27a is a rear fork pivot joint, 30 is a rear wheel shock absorber, 35 is a V-type engine, 36 is the front left cylinder, 27 is the front right cylinder, 38 is the rear cylinder, 39a, 40a, 41
a is a front exhaust pipe, 39b, 40b, 41b are chambers, and 39c, 40c, 41c are silencers.

Claims (1)

[Scope of Claims] 1. A pair of left and right main pipes are installed diagonally downward rearward from the head tube, an engine is disposed below these main pipes, and a rear fork is pivotally mounted behind the main pipes so as to be able to swing up and down. In this motorcycle, a rear wheel shock absorber is attached to the rear fork, and the upper part of the rear wheel shock absorber is pivotally connected to the main pipe at a position above the pivot point of the rear fork, wherein the engine is connected to a front cylinder. It is a V-type engine in which the rear cylinder and the rear cylinder form a V-shape when viewed from the side, and an exhaust system consisting of a small-diameter front exhaust pipe, a larger-diameter chamber, and a muffler connected in this order is attached to each cylinder. All of the front exhaust pipes are housed between the left and right main pipes in plan view, and the small diameter front exhaust pipe extending from the rear cylinder bypasses the upper part of the rear wheel shock absorber, and A motorcycle characterized by having a main pipe passed between the rear parts.