JPH0585400B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an exhaust pipe arrangement structure in a motorcycle equipped with a body frame.

Prior Art In a motorcycle, a cowling made of a light alloy or the like is formed into a streamlined shell, the front end of which is fixed to a head pipe, and extends rearward and downward from the front end to form a part of the vehicle body. There was one in which the engine was inserted from the rear and fixed with several bolts, and an exhaust pipe was extended rearward from the rear end of the cowling (see Japanese Patent Laid-Open No. 56-63570).

Problems to be Solved by the Invention In the above-mentioned conventional motorcycle, the member that fixes and supports the engine is a shell-shaped cowling, so its supporting strength and rigidity are not necessarily sufficient to withstand large impact loads, etc. Therefore, the exhaust pipe at the rear of the engine was not completely protected from external loads.

Means and Effects for Solving the Problems The present invention relates to an improvement of a motorcycle that overcomes such difficulties, and includes a pair of left and right center pillars that extend diagonally downward from the head pipe in a substantially straight line when viewed from the side. , a pair of left and right seat rails each extending rearward from the top of the center pillar;
A pair of left and right back stays are provided that rise upward from the rear part of the center pillar and are coupled to the seat rails, respectively, and an engine support member is provided vertically below approximately the center of the pair of left and right center pillars, and the engine support member is oriented upwardly and forwardly. The upper part of the engine, which has an exhaust port formed on the back side in the direction of cylinder movement, is attached to the engine support member, and the exhaust pipe connected to the exhaust port at the rear of the engine support member is connected between the pair of left and right center pillars and the backstay. The exhaust pipe is extended rearward through the exhaust pipe, and a silencer provided at the rear of the exhaust pipe is housed in the rear cowl.

Since the present invention is configured as described above,
The exhaust pipe connected to the engine's exhaust port can be extended rearward by passing between a pair of left and right center pillars and a pair of left and right backstays without being obstructed by the engine support member above the engine. By surrounding the exhaust pipe with a pair of high-strength left and right center pillars and a backstay, the exhaust pipe can be more effectively protected against external loads.

Further, in the present invention, since the upper part of the engine is supported by the engine support member, the engine is not supported intensively in one place, but can be supported in a distributed manner at a plurality of places, and the engine is lightweight and has high strength and rigidity. It can constitute the body of a motorcycle.

Furthermore, in the present invention, since the exhaust pipes are arranged inside the pair of left and right backstays, the rider does not approach the exhaust pipes when seated, so riding comfort is maintained well, and the exhaust pipes can be used more effectively. protected.

Furthermore, since the exhaust pipe extending rearward from the engine is substantially straight, exhaust resistance is low and output can be improved.

Moreover, in the present invention, since the silencer is also housed in the rear cowl, maneuverability of the vehicle is improved and air resistance is reduced.

Example Examples will be described with reference to the drawings.

Reference numeral 1 denotes a motorcycle, and the front ends of a pair of left and right center pillars 3 are fixed to the upper end of a head pipe 2. The center pillars 3 extend diagonally downward in a substantially straight line from the fixed part of the head pipe 2, and extend from the fixed part to the upper end of the head pipe 2. An under pipe 4 extends obliquely downward to the horizontal rear and is formed integrally with the center pillar 3, thereby forming a triangular vehicle body main frame 21.

Further, a pair of reinforcing stays 5 are provided from the lower end of the head pipe 2 to the approximate center of the center pillar 3, and a pair of seat rails 7 is provided rearward from the joint 6 between the center pillar 3 and the reinforcing stay 5. An engine support member 8 is provided vertically below the engine. In addition, 9 is the seat rail 7
10 is a back stay that connects the substantially central part of the center pillar 3 to the lower part of the center pillar 3, and 10 is a horizontal rod that connects the left and right main frames 21.

The vehicle body frame is formed as described above, the engine 11 is carried into the left and right main frames 21, the upper cylinder head portion 12 is attached to the lower end of the engine support member 11 via screws, etc. The front, lower, and rear parts of the mounting brackets 11 are also integrally fixed to the main frame 21, respectively.
It is fixed by.

At the rear of the main frame 21, a rear arm 15, to which a rear wheel 14 is pivotally attached, is supported so as to be vertically swingable as is well known.

The left and right exhaust pipes 16 are connected to an exhaust port 17 located behind the engine mounting portion of the engine support member 8 described above, pass between the pair of center pillars 3, and are disposed inside the backstay 9. At the same time, it is curved to the level of the seat rail 7, and is curved toward the center of the vehicle body at a position immediately after the rear end of the seat rail 7, and beyond the vehicle center line, the exhaust pipe extends to both the left and right sides of the rear wheel 14.
They cross at the top and are connected to a pair of left and right silencers 18. The silencer 18 is a rear cowling 20 that bulges above the front seat 19.
It is arranged at a position rearward from directly above the rear wheel 14 inside the rear wheel 14 .

[Brief explanation of the drawing]

FIG. 1 is a side view of a motorcycle equipped with an exhaust pipe arrangement structure according to the present invention, and FIG. 2 is a plan view thereof. 1...Motorcycle, 2...Headpipe, 3...
...Center pillar, 4...Under pipe, 5...
...stay, 6...joint, 7...seat rail,
8...Engine support member, 9...Backstay,
10...Horizontal rod, 11...Engine, 12...Cylinder head part, 13...Mounting bracket, 14...
Rear wheel, 15... Rear arm, 16... Exhaust pipe, 17... Exhaust port, 18... Silencer, 19... Seat, 20... Rear cowling,
21...Car body main frame.

Claims (1)

[Claims] 1 A pair of left and right center pillars extending diagonally downward from the head pipe in a substantially straight line when viewed from the side, a pair of left and right seat rails extending rearward from the top of the center pillar, and a pair of left and right seat rails extending upward from the rear of the center pillar. A pair of left and right backstays are respectively connected to the seat rails, and an engine support member is provided vertically below approximately the center of the pair of left and right center pillars, and an exhaust gas is provided on the rear surface of the cylinder facing forward and upward in the direction of travel. The upper part of the engine in which the port is formed is attached to the engine support member, and the exhaust pipe connected to the exhaust port at the rear of the engine support member is passed between the pair of left and right center pillars and the backstay to extend rearward. An exhaust pipe arrangement structure for a motorcycle, characterized in that a silencer provided at the rear of the exhaust pipe is housed in a rear cowl.