Motorcycle

By designing the motorcycle frame so that the exhaust pipe passes through the lower frame rods along the length of the frame, the problem of poor exhaust flow is solved, achieving both smooth exhaust and a compact frame structure.

CN224311895UActive Publication Date: 2026-06-02ZHEJIANG CFMOTO POWER CO LTD

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
ZHEJIANG CFMOTO POWER CO LTD
Filing Date
2025-06-11
Publication Date
2026-06-02

AI Technical Summary

Technical Problem

The exhaust pipes of existing motorcycles have poor exhaust flow due to the centrally located exhaust outlet. The front pipe also blocks the exhaust outlet, requiring the exhaust pipe to bend around the front pipe, which affects the smoothness of exhaust flow.

Method used

Design a motorcycle frame structure in which the exhaust pipe passes between two lower frame rods along the length of the frame, avoiding being routed around the upper or lower frame rods. The part of the exhaust pipe that connects to the engine extends along the length of the frame to improve exhaust flow.

Benefits of technology

It improves the exhaust pipe's exhaust flow, reduces the space occupied by the exhaust pipe in the width direction of the frame, and enhances the frame's structural compactness.

✦ Generated by Eureka AI based on patent content.

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Abstract

The application discloses a motorcycle, which comprises a frame, a body cover, a walking system and a power system, the frame comprises a front frame and a rear frame fixedly connected, the body cover at least partially covers the front frame and the rear frame, the walking system comprises front wheels and rear wheels, the power system comprises an engine and an exhaust pipe, the engine is supported by the front frame and provides power for the rear wheels, the engine is provided with an exhaust port, the exhaust port is connected with the exhaust pipe, an engine accommodating space is formed in the front frame, the engine is installed in the engine accommodating space, the front frame comprises a front connecting frame body, the front connecting frame body is located at the front side of the engine accommodating space, the front connecting frame body comprises one upper frame rod and two lower frame rods, the upper ends of the two lower frame rods are fixed to the upper frame rod, the two lower frame rods are respectively located at the left and right sides of the exhaust port when viewed from front to back, and the exhaust pipe passes through between the two lower frame rods along the length direction of the frame. Through the above arrangement, the exhaust smoothness of the exhaust pipe can be improved.
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Description

Technical Field

[0001] This application relates to the field of two-wheeled vehicle technology, and in particular to a motorcycle. Background Technology

[0002] Motorcycles are a common and widely used mode of transportation. A motorcycle typically consists of a frame, running gear, power system, and suspension system. The frame supports these three systems. However, most existing motorcycle frames are single-beam frames, which include the head tube. The head tube is generally centered along the width of the frame. For engines with a forward-facing exhaust, the exhaust outlet is also usually centered along the width of the frame. This causes the head tube to often obstruct the front of the exhaust outlet, requiring the exhaust pipe to bend appropriately to bypass it. This design results in less than ideal exhaust flow. Utility Model Content

[0003] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide a motorcycle with a high degree of exhaust smoothness of its exhaust pipe.

[0004] To achieve the above objectives, this application adopts the following technical solution:

[0005] A motorcycle includes a frame, body panels, a running gear system, and a power system. The frame includes a front frame and a rear frame fixedly connected, and the body panels at least partially cover the front and rear frames. The running gear includes a front wheel and a rear wheel, with the front wheel at least partially located under the front frame and the rear wheel at least partially located under the rear frame. The power system includes an engine and an exhaust pipe. The engine is supported by the front frame and provides power to the rear wheel. The engine has an exhaust port connected to the exhaust pipe. An engine housing space is formed within the front frame, and the engine is mounted within the engine housing space. The front frame includes a front connecting frame located in front of the engine housing space. The front connecting frame includes an upper frame rod and two lower frame rods, with the upper ends of the two lower frame rods fixed to the upper frame rod. Viewed from front to back, the two lower frame rods are located on the left and right sides of the exhaust port, respectively. The exhaust pipe passes between the two lower frame rods along the length of the frame.

[0006] Furthermore, the wheelbase of the motorcycle ranges from 1270mm to 1560mm, the connection point between the upper frame and the two lower frame members is defined as the fork, and the minimum distance between the uppermost point of the exhaust port and the midpoint of the fork along its own height direction is between 50mm and 80mm.

[0007] Furthermore, a reference plane is defined that is perpendicular to the height direction of the frame and passes through the lowest point of the front wheel. The minimum distance between the midpoint of the fork and the reference plane along the height direction of the frame is 600mm to 700mm.

[0008] Furthermore, the front frame includes a front lower frame body located below the engine housing space. The front lower frame body is connected to the lower end of the lower frame rod. The front lower frame body includes at least one set of front lower tubes. Each set of front lower tubes includes multiple straight beams and at least one bent portion. The straight beams and bent portions are arranged alternately from front to back. The straight beams and bent portions form the boundary of the engine housing space. The front end of the straight beam is not lower than its rear end, and the front end of the bent portion is higher than its rear end.

[0009] Furthermore, the bending section is provided with at least two bending sections, including a first bending section and a second bending section. The first bending section is located in front of the second bending section. The straight beam section includes a first straight beam section and a second straight beam section. The first straight beam section is located in front of the second straight beam section. The first bending section is connected between the lower frame rod and the first straight beam section, and the second bending section is connected between the first straight beam section and the second straight beam section.

[0010] Furthermore, the front lower frame includes two sets of front lower tubes, which are arranged along the width of the frame. The front lower frame also includes a shock-absorbing crossbeam, with two front lower tubes fixedly connected to both ends of the shock-absorbing crossbeam. The engine is supported by the front lower tubes and connected to them.

[0011] Furthermore, a front mounting component and a rear mounting component are fixed on the front lower frame, the engine is mounted on the front mounting component and the rear mounting component, and the shock absorber crossbeam is located between the front mounting component and the rear mounting component along the length of the frame.

[0012] Furthermore, the front frame also includes a rear connecting frame, which is located behind the engine housing and connected to the rear frame. A positioning connector is connected to the rear connecting frame and is connected to the engine to at least limit the position of the engine within the engine housing along the length of the frame. The power system also includes a first bolt and at least two second bolts. The diameter of the first bolt is larger than the diameter of the second bolts. The first bolt is used to connect the positioning connector to the engine. A portion of the second bolts is used to connect the front mounting to the engine, and another portion of the second bolts is used to connect the rear mounting to the engine.

[0013] Furthermore, the front frame includes a side support beam and a front upper frame. The front upper frame is located above the engine housing space. The front end of the side support beam is connected to the front connecting frame, and the rear end of the side support beam is connected to the front upper frame. The connection point between the side support beam and the front connecting frame is defined as the connection part, which is located above the fork. Along the height direction of the frame, the minimum distance between the lowest point of the connection part and the midpoint of the fork along its own height direction ranges from 100mm to 140mm.

[0014] Furthermore, the motorcycle also includes a radiator, with a first heat dissipation connector mounted on the lower frame and a second heat dissipation connector mounted on the upper frame. The radiator is mounted on the two lower frame frames via the first heat dissipation connector and is also mounted on the upper frame via the second heat dissipation connector.

[0015] The aforementioned motorcycle eliminates the need for the exhaust pipe to be routed around the upper or lower frame rods by passing the exhaust pipe between the two lower frame rods along the length of the frame. This reduces the space occupied by the exhaust pipe in the width direction of the frame, improving the structural compactness of the frame. At the same time, the part of the exhaust pipe that connects to the engine extends almost along the length of the frame, allowing the exhaust pipe to more smoothly deliver the exhaust gases from the engine to the outside, thus improving the exhaust flow. Attached Figure Description

[0016] Figure 1 This is a structural diagram of a motorcycle provided in an embodiment of this application.

[0017] Figure 2 This is an installation diagram of the electrical system of a motorcycle provided in an embodiment of this application.

[0018] Figure 3 This is an installation diagram of a low-voltage battery for a motorcycle provided in an embodiment of this application.

[0019] Figure 4 This is a structural diagram of the first mounting front and mounting rear of a motorcycle provided in an embodiment of this application.

[0020] Figure 5 This is a structural diagram of a second type of mounting front and rear section of a motorcycle provided in an embodiment of this application.

[0021] Figure 6 This is a structural diagram of the motorcycle frame provided in an embodiment of this application.

[0022] Figure 7 This is a diagram showing the installation structure of the power system and frame of a motorcycle provided in an embodiment of this application.

[0023] Figure 8 Examples of this application Figure 7 Structural installation diagram at point A.

[0024] Figure 9 This is a schematic diagram of the front wheel and frame of a motorcycle provided in an embodiment of this application.

[0025] Figure 10 The image shows the effect of the first finite element analysis of the motorcycle provided in the embodiment of this application.

[0026] Figure 11The diagram shows the effect of a second finite element analysis of a motorcycle provided in an embodiment of this application.

[0027] Figure 12 The diagram shows the effect of a third finite element analysis of a motorcycle provided in the embodiments of this application.

[0028] Figure 13 Examples of this application Figure 9 The structural diagram at point B in the middle.

[0029] Figure 14 This is a diagram showing the installation structure of the front connecting part and the front wheel of a motorcycle provided in an embodiment of this application.

[0030] Figure 15 This is a diagram showing the installation structure of the through-part and rear connection part of a motorcycle provided in an embodiment of this application.

[0031] Figure 16 This is a structural diagram of the motorcycle frame, fuel tank, and shock absorber provided in an embodiment of this application. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0033] Motorcycles include street bikes, touring bikes, and off-road bikes.

[0034] like Figure 1 and Figure 2 As shown, this application provides a motorcycle 100, which is described using an off-road motorcycle as an example.

[0035] The motorcycle 100 includes a frame 11, body panels 12, a running system 13, a power system 14, an electrical system 15, and a low-voltage battery 16.

[0036] For ease of expression, the definitions in this application are as follows: Figure 1 The directions shown are front, back, left, right, up, and down. The front-back direction refers to the length of the motorcycle frame 11, the left-right direction refers to the width of the motorcycle frame 11, and the up-down direction refers to the height of the motorcycle frame 11. In this embodiment, the front, back, left, right, up, and down directions are based on the motorcycle 100 traveling on a level surface, not on a sloping surface.

[0037] The frame 11 serves as the basic framework of the motorcycle 100, supporting the body panel 12, running system 13, power system 14, electrical system 15, and low-voltage battery 16. The body panel 12 at least partially covers and connects to the frame 11, protecting the internal components of the motorcycle 100. The running system 13 is at least partially located beneath the frame 11. The electrical system 15, supported by the frame 11, controls the operation of the motorcycle 100. The low-voltage battery 16, also supported by the frame 11, supplies power to the electrical system 15.

[0038] Specifically, the running gear 13 includes a front wheel 131 and a rear wheel 132. The frame 11 includes a front frame 111 and a rear frame 112 fixedly connected together. The front wheel 131 is connected to the front frame 111, and the rear wheel 132 is connected to the rear frame 112. The front wheel 131 is at least partially located below the front frame 111, and the rear wheel 132 is at least partially located below the rear frame 112. More specifically, a front suspension is connected to the front frame 111, and the front wheel 131 is connected to the front frame 111 via the front suspension. A rear suspension is connected to the rear frame 112, and the rear wheel 132 is connected to the rear frame 112 via the rear suspension.

[0039] The body panel 12 at least partially covers the front frame 111 and the rear frame 112.

[0040] The power system 14 is supported by the front frame 111 and provides power to the running gear 13. The power system 14 can be connected to the front wheel 131 or to both the front wheel 131 and the rear wheel 132.

[0041] like Figure 2 As shown, in one embodiment, the electrical system 15 includes a start relay 151, an on-board diagnostic unit 152, and an electronic control unit 153. The start relay 151 can start the motorcycle 100, enabling it to begin operation. The on-board diagnostic unit 152 can monitor for abnormalities in components such as the power system 14 in real time. The electronic control unit 153, acting as the controller of the motorcycle 100, can control the normal operation of the motorcycle 100.

[0042] Specifically, the low-voltage battery 16 is electrically connected to the start relay 151, the on-board diagnostic unit 152, and the electronic control unit 153, thereby enabling the low-voltage battery 16 to provide power to the start relay 151, the on-board diagnostic unit 152, and the electronic control unit 153.

[0043] More specifically, the rear frame 112 includes two rear frame assemblies 1121 and a mounting base 1122. The two rear frame assemblies 1121 are arranged along the width direction of the frame 11, and the mounting base 1122 is installed between the two rear frame assemblies 1121. The two rear frame assemblies 1121 and the mounting base 1122 together form a mounting space, which is located above the mounting base 1122. The low-voltage battery 16, the starter relay 151, the on-board diagnostic unit 152, and the electronic control unit 153 are installed within the mounting space.

[0044] Through the above arrangement, the starting relay 151, on-board automatic diagnostic unit 152, electronic control unit 153, and low-voltage battery 16 are integrated into the mounting base 1122, placing these electrical components within the mounting space. This concentrates the space occupied by these components within the mounting space, facilitating centralized management and improving the space utilization of the motorcycle 100. Simultaneously, the mounting space is located above the mounting base 1122, allowing the electrical system 15 and low-voltage battery 16 within the mounting space to be protected by the frame 11 and body panels 12. This prevents interference from the external environment, extending the service life of the electrical system 15 and low-voltage battery 16.

[0045] like Figure 2 and Figure 3As shown, the low-voltage battery 16 extends along a predetermined direction 101, which is perpendicular to the width direction of the frame 11, and the angle α formed by the predetermined direction 101 and the horizontal plane 102 ranges from 15° to 20°. Specifically, the angle α formed by the predetermined direction 101 and the horizontal plane 102 ranges from 16° to 19°. More specifically, the angle α formed by the predetermined direction 101 and the horizontal plane 102 ranges from 17° to 18°. The low-voltage battery 16 has a centerline parallel to the predetermined direction 101. The low-voltage battery 16 includes an upper end 161 and a lower end 162 distributed along the predetermined direction 101. The upper end 161 is equipped with an electrode connector 1611 for connecting to an external circuit, and the lower end 162 is the base of the low-voltage battery 16. By arranging the low-voltage battery 16 within the installation space according to the aforementioned angle range, it is possible to avoid excessive installation angle of the low-voltage battery 16, which would result in excessive space occupation by the low-voltage battery 16 in the height direction of the frame 11, thereby improving the structural compactness of the rear frame 112. Simultaneously, it also avoids excessive installation angle of the low-voltage battery 16, which could affect the electrolyte flow and thus prevent safety issues, thereby improving the operational safety of the low-voltage battery 16 and facilitating its normal operation. The starting relay 151 is located behind the low-voltage battery 16, with its upper end 161 at least partially located behind the lower end 162, so that the electrode connector 1611 is located behind the low-voltage battery 16, and the electrode connector 1611 is electrically connected to the starting relay 151. With the above arrangement, the electrode connector 1611 is positioned close to the starter relay 151, which shortens the distance between the electrode connector 1611 and the starter relay 151. This simplifies the wiring complexity between the electrode connector 1611 and the starter relay 151 and reduces the length of the wire between them. This reduces the space occupied by the wire between the low-voltage battery 16 and the starter relay 151, thereby improving the space utilization and structural compactness of the motorcycle 100.

[0046] The rear frame 112 also includes a crossbeam 1123 mounted between the two rear frame assemblies 1121. The crossbeam 1123 is at least partially located above the connection between the electrode connector 1611 and the starter relay 151, and when viewed from the height of the frame 11, the crossbeam 1123 at least partially overlaps with the connection. The electrical system 15 also includes a wiring harness assembly 154, which is at least partially located below the crossbeam 1123. With this configuration, external forces can be absorbed and transmitted to the two rear frame assemblies 1121 through the crossbeam 1123, preventing external forces from directly acting on the connection between the electrode connector 1611 and the starter relay 151. This protects the connection between the electrode connector 1611 and the starter relay 151, improving the stability of the connection and enhancing the safety of the low-voltage battery 16 and the starter relay 151.

[0047] like Figure 1 and Figure 2 As shown, the motorcycle 100 also includes a seat 17, which is at least partially connected to the rear frame 112 and covers the mounting space. Viewed from the height of the frame 11, the seat 17 at least partially overlaps with the rear frame 112. Specifically, the crossbeam 1123 at least partially protrudes upward to form a support portion 1123a, which connects to or abuts against, so that the support portion 1123a supports the seat 17, thereby improving the stability of the seat 17 during use. Furthermore, both ends of the crossbeam 1123 along the width direction of the frame 11 are lower than the lower surface of the support portion 1123a to increase the space below the support portion 1123a, thus facilitating the placement of a larger low-voltage battery 16.

[0048] As an optional implementation, the support 1123a is equipped with an unlocking element 1123b for unlocking the seat cushion 17, allowing the seat cushion 17 to connect to or separate from the support 1123a, thereby enabling the seat cushion 17 to open or close. Alternatively, the unlocking element 1123b is connected to a cable, with a lock connected to the end of the cable away from the unlocking element 1123b. The user can insert a key into the lock and turn it, causing the cable to control the unlocking element 1123b to unlock the seat cushion 17, allowing the seat cushion 17 to separate from the support 1123a.

[0049] The mounting base 1122 has a mounting groove structure 1122a, which includes four side walls and a bottom surface. The bottom surface and the four side walls surround a battery cavity, in which the low-voltage battery 16 is installed. This arrangement allows the low-voltage battery 16 to be stably fixed on the mounting base 1122, reducing the shaking of the low-voltage battery 16 during motorcycle 100 operation and improving its stability on the mounting base 1122. The four side walls and the bottom surface of the battery cavity are in close contact with the low-voltage battery 16, ensuring its stable installation within the battery cavity.

[0050] In this application, the mounting base 1122 can be substantially plate-shaped to increase the contact area between the low-voltage battery 16 and the mounting base 1122, and to increase the contact area between a portion of the electrical system 15 and the mounting base 1122, thereby improving the stability of the low-voltage battery 16 and a portion of the electrical system 15 on the mounting base 1122. The mounting groove structure 1122a can be formed by a downward recess in the plate-shaped mounting base 1122.

[0051] It should be noted that the mounting base 1122 can be of other shapes, and this application does not impose any restrictions, as long as the low-voltage battery 16 and part of the electrical system 15 can be installed on the mounting base 1122.

[0052] like Figure 2 and Figure 4 As shown, since the electronic control unit 153 needs to be mounted on a mounting surface with a small tilt angle to improve the control accuracy of the electronic control unit 153, in one embodiment, the mounting base 1122 includes a mounting front portion 1122b, a mounting middle portion 1122c, and a mounting rear portion 1122d connected in sequence. The upper surface of the mounting front portion 1122b is substantially flat, the upper surface of the mounting rear portion 1122d is substantially flat, and the angle β between the upper surface of the mounting rear portion 1122d and the horizontal plane 102 is smaller than the angle θ between the upper surface of the mounting front portion 1122b and the horizontal plane 102. The electronic control unit 153 is mounted on the mounting rear portion 1122d. Since the tilt angle of the mounting rear portion 1122d is small, the above arrangement can improve the control accuracy of the electronic control unit 153. In this embodiment, the mounting groove structure 1122a is located in the mounting middle portion 1122c.

[0053] In this application, the electrical system 15 also includes a fuse box 155 and an auxiliary relay 156 installed in the installation space. The fuse box 155, the auxiliary relay 156, and the on-board automatic diagnostic unit 152 are located in front of the low-voltage battery 16. By arranging the fuse box 155, the auxiliary relay 156, and the on-board automatic diagnostic unit 152 in front of the low-voltage battery 16, the utilization rate of the space in front of the low-voltage battery 16 can be increased, thereby improving the space utilization rate and structural compactness of the motorcycle 100.

[0054] In this application, the front mounting portion 1122b has multiple mounting protrusions 1122e, and the fuse box 155, auxiliary relay 156, and on-board diagnostic unit 152 are all fixed to the front mounting portion 1122b via the mounting protrusions 1122e. By providing multiple mounting protrusions 1122e, interference between the fuse box 155, auxiliary relay 156, and on-board diagnostic unit 152 can be avoided, thereby improving the installation stability of the fuse box 155, auxiliary relay 156, and on-board diagnostic unit 152, which is beneficial to the normal operation of the aforementioned electrical components. It should be noted that each mounting protrusion 1122e has a screw hole, and the fuse box 155, auxiliary relay 156, and on-board diagnostic unit 152 can all be fixed to the corresponding mounting protrusion 1122e by bolts and screw holes.

[0055] like Figure 2 and Figure 5 As shown, in another alternative embodiment, the mounting base 1122 further includes an adapter 1122f mounted on the rear mounting portion 1122d. The upper surface of the front mounting portion 1122b is substantially flat, and the upper surface of the adapter 1122f is also substantially flat. The angle γ between the upper surface of the adapter 1122f and the horizontal plane 102 is smaller than the angle θ between the upper surface of the front mounting portion 1122b and the horizontal plane 102. The electronic control unit 153 is mounted on the adapter 1122f. Because the tilt angle of the adapter 1122f is small, the above arrangement can improve the control accuracy of the electronic control unit 153.

[0056] It should be noted that, in this embodiment, due to the provision of the adapter 1122f, there is no need to limit the specific shape of the mounting rear part 1122d, which is beneficial to adjust the shape of the mounting rear part 1122d according to the structure of the motorcycle 100, thereby improving the adaptability of the mounting seat 1122.

[0057] like Figure 6 and Figure 7As shown, in one embodiment, the power system 14 includes an engine 141 and an exhaust pipe 142. The engine 141 is supported by the front frame 111 and provides power to the running system 13. The engine 141 is provided with an exhaust port 1411, which is connected to the exhaust pipe 142.

[0058] The front frame 111 has an engine housing space 1110, and the engine 141 is installed in the engine housing space 1110. With the above arrangement, the engine 141 is placed in the engine housing space 1110 in the front frame 111, so that the front frame 111 can enclose the engine 141, thereby preventing the engine 141 from being hit or impacted by external impurities, and thus extending the service life of the engine 141.

[0059] Specifically, the front frame 111 includes a front connecting frame 1111, a front lower frame 1113, a side support beam 1115, a front upper frame 1116, and a rear connecting frame 1117. The front connecting frame 1111 is located in front of the engine housing space 1110. The front lower frame 1113 is connected to the front connecting frame 1111 and is located below the engine housing space 1110. The front upper frame 1116 is connected to the front connecting frame 1111 and is located above the engine housing space 1110. The two ends of the side support beam 1115 are connected to the front upper frame 1116 and the front connecting frame 1111, respectively. The rear connecting frame 1117 is located behind the engine housing space 1110. The rear connecting frame 1117 connects the front upper frame 1116 and the front lower frame 1113. The rear connecting frame 1117 is also connected to the rear frame 112.

[0060] The front connecting frame 1111 includes an upper frame rod 1111a and two lower frame rods 1111b. The upper ends 161 of the two lower frame rods 1111b are fixed to the upper frame rod 1111a. The exhaust pipe 142 passes through the space between the two lower frame rods 1111b along the length of the frame 11.

[0061] The above configuration allows one upper frame rod 1111a and two lower frame rods 1111b to form a herringbone structure, thereby improving the stability of the front connecting frame 1111 structure, thus increasing the structural strength of the frame 11, and further increasing the structural strength of the motorcycle 100.

[0062] Furthermore, viewed from front to back, the two lower frame rods 1111b are located on the left and right sides of the exhaust port 1411, respectively. The exhaust pipe 142 passes between the two lower frame rods 1111b along the length of the frame 11. This eliminates the need for the exhaust pipe 142 to be routed around the upper frame rod 1111a or the lower frame rod 1111b, thereby reducing the space occupied by the exhaust pipe 142 in the width direction of the frame 11 and improving the structural compactness of the frame 11. At the same time, the above arrangement ensures that the portion of the exhaust pipe 142 that connects to the engine 141 extends substantially along the length of the frame 11, allowing the exhaust pipe 142 to more smoothly deliver the exhaust gas discharged from the engine 141 to the outside.

[0063] In this application, the upper frame rod 1111a and the lower frame rod 1111b can be hollow or solid, as long as they can support the front connecting frame 1111. This application does not impose any restrictions on this.

[0064] like Figure 8 As shown, the wheelbase L of the motorcycle 100 ranges from 1270mm to 1560mm. The connection point between the upper frame rod 1111a and the two lower frame rods 1111b is defined as the fork 1112. Along the height direction of the frame 11, the minimum distance H1 between the uppermost point of the exhaust port 1411 and the midpoint of the fork 1112 along its own height direction ranges from 50mm to 80mm. The midpoint of the fork 1112 along its own height direction can be understood as the intersection of the centerline of the upper frame rod 1111a and the centerline of the lower frame rods 1111b. Specifically, the wheelbase L of the motorcycle 100 ranges from 1340mm to 1490mm; the minimum distance H1 between the uppermost point of the exhaust port 1411 and the midpoint of the fork 1112 along its own height direction ranges from 55mm to 75mm. More specifically, the wheelbase L of the motorcycle 100 ranges from 1415mm to 1418mm; the minimum distance H1 between the uppermost point of the exhaust port 1411 and the midpoint of the fork 1112 along its own height direction ranges from 60mm to 70mm.

[0065] Since the temperature near the exhaust port 1411 is high when the motorcycle 100 is in motion, the above-mentioned design, while ensuring the wheelbase L meets the specified range, prevents the minimum distance H1 between the midpoint of the fork 1112 along its height direction and the exhaust port 1411 from becoming too close. This avoids thermal deformation of the fork 1112, thus extending its service life. Furthermore, it prevents the fork 1112 from absorbing excessive heat due to its proximity to the exhaust port 1411, preventing heat transfer from the exhaust port 1411 to the frame 11 and thus minimizing its impact on the rider, thereby improving the comfort of the motorcycle 100. Simultaneously, it prevents the minimum distance H1 between the midpoint of the fork 1112 along its height direction and the exhaust port 1411 from becoming too large, reducing the height of the front frame 111 in the frame 11 height direction and improving the structural compactness of the front frame 111.

[0066] like Figure 9 As shown, a reference plane 106 is defined, perpendicular to the height direction of the frame 11 and passing through the lowest point of the front wheel 131. Along the height direction of the frame 11, the minimum distance H2 between the midpoint of the fork 1112 along its own height direction and the reference plane 106 along the height direction of the frame 11 ranges from 600mm to 700mm. Specifically, along the height direction of the frame 11, the minimum distance H2 between the midpoint of the fork 1112 along its own height direction and the reference plane 106 along the height direction of the frame 11 ranges from 620mm to 680mm. More specifically, along the height direction of the frame 11, the minimum distance H2 between the midpoint of the fork 1112 along its own height direction and the reference plane 106 along the height direction of the frame 11 ranges from 640mm to 660mm. By setting the minimum distance H2 as described above, the structural strength of the frame 11 can be improved by avoiding the minimum distance H2 being too small. It can also prevent the center of gravity of the motorcycle 100 from being too high due to the minimum distance H2 being too large, thereby improving the driving stability of the motorcycle 100 and facilitating safe driving of the motorcycle 100 in different environments. At the same time, it can also prevent the material waste of the frame 11 due to the minimum distance H2 being too large.

[0067] like Figure 7 and Figure 9 As shown, the front lower frame 1113 is connected to the lower ends of the two lower frame rods 1111b. The front lower frame 1113 includes at least one set of front lower tubes, each set of front lower tubes including multiple straight beam sections 1113e and at least one bent section 1113f. The straight beam sections 1113e and bent sections 1113f are arranged alternately from front to back, and the straight beam sections 1113e and bent sections 1113f are used to define the boundary of the engine housing space 1110. The front end of the straight beam section 1113e is not lower than the rear end of the straight beam section 1113e, and the front end of the bent section 1113f is higher than the rear end of the bent section 1113f.

[0068] Specifically, the bending portion 1113f includes a first bending portion 1113a and a second bending portion 1113b, with the first bending portion 1113a located in front of the second bending portion 1113b. The straight beam portion 1113e includes a first straight beam portion 1113g and a second straight beam portion 1113h, with the first straight beam portion 1113g located in front of the second straight beam portion 1113h. The first bending portion 1113a connects the lower support rod 1111b and the first straight beam portion 1113g, and the second bending portion 1113b connects the first straight beam portion 1113g and the second straight beam portion 1113h.

[0069] By configuring the first bend 1113a and the second bend 1113b as described above, excessive stress concentration can be avoided when the front lower frame 1113 is subjected to force, thereby improving the structural strength of the frame 11. Simultaneously, configuring the first bend 1113a and the second bend 1113b allows the outline of the front lower frame 1113 to match the outline of the engine 141, improving the front frame 111's coverage of the engine 141 and thus enhancing its protective effect. Furthermore, it reduces the space occupied by the frame 11, thereby improving the space utilization rate of the frame 11.

[0070] In this application, the engine 141 is connected to the front lower frame 1113. The front lower frame 1113 includes two sets of front lower tubes, which are arranged along the width direction of the frame 11. The front lower frame 1113 also includes a shock-absorbing crossbeam 1114, with the two ends of the shock-absorbing crossbeam 1114 respectively fixedly connected to the two front lower tubes. The engine 141 is supported by and connected to the front lower tubes.

[0071] With the above configuration, the front underframe 1113 can support the engine 141, thereby preventing the engine 141 from shaking when the motorcycle 100 is in motion, thus improving the stability of the engine 141 and ensuring its normal operation. Simultaneously, the shock-absorbing crossbeam 1114 can increase the structural strength of the front underframe 1113, reducing the impact of engine 141 vibrations on the front underframe 1113, thereby improving the stability of the frame 11 and ultimately enhancing the stability of the motorcycle 100 while in motion.

[0072] Furthermore, in this embodiment, the shock-absorbing crossbeam 1114 is connected to the second bend 1113b, thereby enabling the shock-absorbing crossbeam 1114 to support the second bend 1113b, so as to further reduce the impact of engine 141 vibration on the front frame 111.

[0073] The front mounting component 1113c and the rear mounting component 1113d are fixed on the front lower frame 1113, and the engine 141 is mounted on the front mounting component 1113c and the rear mounting component 1113d, thereby improving the connection strength between the engine 141 and the front lower frame 1113.

[0074] Specifically, along the length of the frame 11, the shock-absorbing crossbeam 1114 is located between the front mount 1113c and the rear mount 1113d, which allows the shock-absorbing crossbeam 1114 to balance and absorb the vibrations transmitted from the engine 141 to the front mount 1113c and the rear mount 1113d.

[0075] In this embodiment, the side support beam 1115 includes a front end and a rear end. The front end of the side support beam 1115 is connected to the front connecting frame 1111, and the rear end of the side support beam 1115 is connected to the front upper frame 1116. The connection point between the side support beam 1115 and the front connecting frame 1111 is defined as the connection part 1115a, which is located above the fork part 1112. Along the height direction of the frame 11, the minimum distance H3 between the midpoint of the fork part 1112 along its own height direction and the lowest point of the connection part 1115a is in the range of 100mm to 140mm. Specifically, the minimum distance H3 between the midpoint of the fork part 1112 along its own height direction and the lowest point of the connection part 1115a is in the range of 110mm to 130mm. More specifically, the minimum distance H3 between the midpoint of the bifurcation 1112 along its own height direction and the lowest point of the connecting part 1115a in the height direction ranges from 115mm to 125mm.

[0076] The above settings can prevent the height of the connecting part 1115a from being too high or too low, which would affect the supporting effect of the side support beam 1115 on the front connecting frame 1111, thus avoiding uneven distribution of structural strength of the front connecting frame 1111 and improving the overall structural strength of the frame 11.

[0077] like Figure 7 and Figure 9 As shown, the motorcycle 100 also includes a radiator 18. A first heat dissipation connector 1111c is mounted on the lower frame rod 1111b, and a second heat dissipation connector 1111d is mounted on the upper frame rod 1111a. The radiator 18 is mounted on the two lower frame rods 1111b via the first heat dissipation connector 1111c, and the radiator 18 is also mounted on the upper frame rod 1111a via the second heat dissipation connector 1111d. With the above arrangement, two first heat dissipation connectors 1111c and one second heat dissipation connector 1111d are provided between the radiator 18 and the front connecting frame 1111, thereby enabling the radiator 18 to be triangularly positioned and mounted on the front connecting frame 1111, thus improving the stability of the connection between the radiator 18 and the front connecting frame 1111.

[0078] The rear connecting frame 1117 is connected to a positioning connector 1117a, and the engine 141 is connected to the positioning connector 1117a to at least limit the position of the engine 141 within the engine housing space 1110 along the length direction of the frame 11. The power system 14 also includes a first bolt (not shown) and at least two second bolts (not shown). The diameter of the first bolt is larger than the diameter of the second bolts. The first bolt is used to connect the positioning connector 1117a to the engine 141. A portion of the second bolts are used to connect the front mounting piece 1113c to the engine 141, and another portion of the second bolts are used to connect the rear mounting piece 1113d to the engine 141.

[0079] With the above settings, when the engine 141 is connected to the front frame 111, the engine 141 is first fixed to the positioning connector 1117a on the rear connecting frame 1117 to position the relative position of the engine 141 and the front frame 111. Then, the engine 141 is connected to the front mounting part 1113c and the rear mounting part 1113d on the front lower frame 1113, thereby improving the convenience of installing the engine 141 and the front frame 111.

[0080] like Figure 10 , Figure 11 and Figure 12 As shown, this application also provides renderings of three finite element analyses. Finite element analysis is used to simulate and optimize the structural strength, vibration characteristics, fatigue life, and lightweight design of different components of the motorcycle 100. The motorcycle 100 also includes a left footrest 19 for the passenger (see reference). Figure 1 ). Figure 10 This represents the magnitude of the force exerted on the connection between the left foot pedal 19 and the frame 11 in the X-axis direction at different engine speeds of engine 141. Figure 11 This represents the magnitude of the force exerted on the connection between the left foot pedal 19 and the frame 11 in the Y-axis direction at different engine speeds of engine 141. Figure 12 This represents the magnitude of the force exerted on the part of the left foot pedal 19 connected to the frame 11 in the Z-axis direction at different engine speeds of the engine 141. Figure 10 , Figure 11 , Figure 12 The horizontal axis represents the engine speed of 141, and the vertical axis represents the root mean square of stress and displacement. The red curves represent the finite element analysis curves of existing motorcycles, and the green curves represent the finite element analysis curves of the motorcycle 100 of this application.

[0081] according to Figure 10 It is understood that the part of the left foot pedal 19 of the motorcycle 100 in this application that is connected to the frame experiences less force in the X-axis direction than existing motorcycles when the engine 141 is operating at different speeds, thereby extending the service life of the foot pedal 19.

[0082] according to Figure 11 It is understood that the part of the motorcycle 100 in this application that connects the left foot pedal 19 to the frame experiences less force in the Y-axis direction than existing motorcycles when the engine 141 operates at different speeds, thereby extending the service life of the foot pedal 19.

[0083] according to Figure 12 It is understood that the part of the left foot pedal 19 of the motorcycle 100 in this application that is connected to the frame experiences less force in the Z-axis direction than existing motorcycles when the engine 141 is operating at different speeds, thereby extending the service life of the foot pedal 19.

[0084] Because the motorcycle 100 mostly travels in unconventional terrain, it experiences significant vibrations during operation, resulting in the frame 11 being subjected to considerable forces. For example... Figure 13 As shown, in one embodiment, a node structure 21 is provided at the connection between the front frame 111 and the rear frame 112. The node structure 21 can improve the rigidity of the connection between the front frame 111 and the rear frame 112, so as to avoid large relative swaying of the front frame 111 and the rear frame 112 during the operation of the motorcycle 100, thereby improving the stability of the frame 11 and thus improving the structural strength of the frame 11.

[0085] In this application, the node structure 21 includes a main body 211, an interpenetrating part 212 and a fitting part 213, both of which are fixed to the main body 211.

[0086] The front frame 111 is provided with a front connecting part 1118, and the rear frame 112 is provided with a rear connecting part 1124. The front connecting part 1118 is the part that connects the front upper frame 1116 and the rear connecting frame 1117, and the rear connecting part 1124 is the part that connects the rear frame 112 and the node structure 21.

[0087] More specifically, the insertion part 212 is inserted into the rear connecting part 1124 and welded to the rear connecting part 1124, and the fitting part 213 is fitted to the outer peripheral wall of the front connecting part 1118 and welded to the front connecting part 1118.

[0088] Alternatively, as another implementation, the insert 212 is inserted into the front connecting part 1118 and welded to the front connecting part 1118, and the fitting part 213 is fitted to the outer peripheral wall of the rear connecting part 1124 and welded to the rear connecting part 1124.

[0089] The beneficial effects of the above configuration will be explained by taking the insertion part 212 into the rear connecting part 1124 and the fitting part 213 fitting against the outer peripheral wall of the front connecting part 1118 as an example.

[0090] Through the above configuration, the interlocking portion 212 welds and fixes the node structure 21 to the front connecting portion 1118, and the fitting portion 213 welds and fixes the node structure 21 to the rear connecting portion 1124, thereby improving the connection strength between the node structure 21 and the front frame 111, and between the node structure 21 and the rear frame 112, thus improving the stability of the connection between the front frame 111 and the rear frame 112. Simultaneously, the interlocking portion 212 is inserted into the front connecting portion 1118, thereby increasing the contact area between the interlocking portion 212 and the front connecting portion 1118, thereby improving the torsional resistance when the interlocking portion 212 and the front connecting portion 1118 are connected, and further improving the stability of the connection between the node structure 21 and the front frame 111. Furthermore, the fitting portion 213 fits against the outer peripheral wall of the rear connecting portion 1124, thereby increasing the welding area between the fitting portion 213 and the rear connecting portion 1124, further improving the stability of the connection between the node structure 21 and the rear frame 112.

[0091] In this application, the node structure 21 further includes a first connecting rib 214 and a second connecting rib 215, both of which are fixedly connected between the fitting portion 213 and the main body portion 211. The first connecting rib 214 and the second connecting rib 215 are essentially plate-shaped. A plane perpendicular to the thickness direction of the first connecting rib 214 and passing through the center of its thickness is defined as a first thickness reference surface 107, and a plane perpendicular to the thickness direction of the second connecting rib 215 and passing through its center of thickness is defined as a second thickness reference surface 108. The first thickness reference surface 107 and the second thickness reference surface 108 are essentially perpendicular. With the above configuration, the rigidity between the main body 211 and the fitting part 213 can be increased by the basically vertical first connecting rib 214 and the second connecting rib 215, so as to avoid torsional deformation between the main body 211 and the fitting part 213, thereby increasing the structural strength of the node structure 21, which is conducive to improving the connection stability between the front frame 111 and the rear frame 112, and thus improving the structural strength of the frame 11.

[0092] Meanwhile, during the operation of the motorcycle 100, the front frame 111 and the rear frame 112 will undergo relative torsion, which will cause the node structure 21 to be subjected to forces in multiple directions. Through the above-mentioned arrangement, the first connecting rib 214 and the second connecting rib 215 can disperse the stress to avoid stress concentration, thereby improving the stability of the connection between the front frame 111 and the rear frame 112, and thus improving the structural stability of the frame 11.

[0093] In this embodiment, the first thickness reference surface 107 is substantially perpendicular to the width direction of the frame 11, and the line segment between the main body 211 and the fitting part 213 that is closest to each other is substantially located within the second thickness reference surface 108. That is, the second connecting rib 215 is connected to the main body 211 and the fitting part 213 at the closest position, which helps to support the main body 211 and the fitting part 213.

[0094] In this application, the rear connecting frame 1117 is located behind and below the front upper frame 1116. The front upper frame 1116 and the rear connecting frame 1117 are integrally formed, and a bent section is formed at the connection between the front upper frame 1116 and the rear connecting frame 1117. The front connecting part 1118 is the bent section, and the fitting part 213 is fitted to the bent section. The fitting part 213 includes a first fitting sub-part 2131 and a second fitting sub-part 2132. The first fitting sub-part 2131 is fitted to the outer peripheral wall of the front upper frame 1116 and welded to the front upper frame 1116. The second fitting sub-part 2132 is fitted to the outer peripheral wall of the rear connecting frame 1117 and welded to the rear connecting frame 1117.

[0095] With the above configuration, the first bonding part 2131 and the second bonding part 2132 are connected at different positions on the front frame 111 to avoid the bonding part 213 being concentrated and fixed in a local area of ​​the front frame 111. This increases the bonding area between the bonding part 213 and the front frame 111, thereby improving the stability of the connection between the bonding part 213 and the front frame 111.

[0096] In this embodiment, the bonding area between the first bonding sub-part 2131 and the front upper frame 1116 is greater than the bonding area between the second bonding sub-part 2132 and the rear connecting frame 1117.

[0097] Since the force on the front upper frame 1116 is greater than that on the rear connecting frame 1117, the stability of the connection between the node structure 21 and the front frame 111 can be improved by the above arrangement.

[0098] like Figure 14 As shown, in this embodiment, the structural strength of the bent front connecting portion 1118 is relatively low. Therefore, in this application, by connecting the fitting portion 213 to the front connecting portion 1118, the stress at the front connecting portion 1118 can be dispersed. Furthermore, viewed from the width direction of the frame 11, the node structure 21 basically forms a triangular structure, thereby improving the structural strength of the front connecting portion 1118 and thus enhancing the structural strength of the frame 11. The side containing the fitting portion 213 in the triangular structure is an arc.

[0099] In this application, the wheelbase L of the motorcycle 100 ranges from 1270mm to 1560mm; the minimum distance H4 between the rotation center line of the front connecting part 1118 and the front wheel 131 along the height direction of the frame 11 ranges from 310mm to 350mm. Specifically, the wheelbase L of the motorcycle 100 ranges from 1340mm to 1490mm; the minimum distance H4 between the rotation center line of the front connecting part 1118 and the front wheel 131 along the height direction of the frame 11 ranges from 320mm to 340mm. More specifically, the wheelbase L of the motorcycle 100 ranges from 1415mm or 1418mm; the minimum distance H4 between the rotation center line of the front connecting part 1118 and the front wheel 131 along the height direction of the frame 11 ranges from 325mm to 335mm.

[0100] With the above-described configuration, when the wheelbase L is within the aforementioned range, it avoids setting the front connecting part 1118 too high, which would increase the rider's seating height and thus improve the riding experience of the motorcycle 100. At the same time, it also avoids setting the front connecting part 1118 too low, which could affect the structural strength of the front frame 111.

[0101] like Figure 13 and Figure 15 As shown, the interpenetrating portion 212 is formed with an interpenetrating slope 2121 for beveling welding with the rear connecting portion 1124. The rear connecting portion 1124 includes an insertion hole 1124a for the interpenetrating portion 212 to be inserted into. This allows the slope 2121 to be connected to the rear connecting portion 1124 by beveling welding, thereby improving the connection strength and load-bearing capacity between the interpenetrating portion 212 and the rear connecting portion 1124 after welding, and further improving the stability when the interpenetrating portion 212 and the rear connecting portion 1124 are connected, so as to improve the stability of the connection between the node structure 21 and the rear frame 112.

[0102] It should be noted that groove welding is a process that involves machining the edge of the workpiece to form a groove (an angled or specially shaped groove) and then welding within the groove.

[0103] In this embodiment, the ratio of the length D1 of the insertion portion 212 inserted into the insertion hole 1124a to the orifice diameter φ of the insertion hole 1124a ranges from 0.16 to 0.26. Specifically, the ratio of the length D1 of the insertion portion 212 inserted into the insertion hole 1124a to the orifice diameter φ of the insertion hole 1124a ranges from 0.19 to 0.24. More specifically, the ratio of the length D1 of the insertion portion 212 inserted into the insertion hole 1124a to the orifice diameter φ of the insertion hole 1124a ranges from 0.21 to 0.24. With the above settings, the length D1 can be avoided from being too short, thereby improving the connection strength after welding the insertion portion 212 and the rear connecting portion 1124; the length D1 can also be avoided from being too long, thus avoiding material waste.

[0104] like Figure 13 As shown, the front upper frame 1116 is mainly composed of two sets of tubular structures arranged along the width direction of the frame 11. The rear connecting frame 1117 is also mainly composed of two sets of tubular structures arranged along the width direction of the frame 11. The two sets of tubular structures of the front upper frame 1116 are connected one-to-one with the two sets of tubular structures of the rear connecting frame 1117, forming a front connecting part 1118 at each connection point. The rear frame 112 is also mainly composed of two sets of tubular structures arranged along the width direction of the frame 11. The two sets of tubular structures of the rear frame 112 are connected one-to-one with the two front connecting parts 1118, forming a node structure 21 at each connection point. The two sets of tubular structures of the rear frame 112 are the two rear frame components 1121. Two sets of node structures 21 are arranged along the width direction of the frame 11, and a connecting rod 22 connects the two sets of node structures 21. Both sets of node structures 21 have socket holes, and both ends of the connecting rod 22 have connecting bevel surfaces for welding to the nearest socket bevel, so that the bevel surfaces of the connecting rod 22 are connected to the two sets of node structures 21 by full welding. Specifically, both main bodies 211 have socket holes, and both ends of the connecting rod 22 are located in the socket holes of the two main bodies 211, so that the connecting rod 22 can be connected to the two main bodies 211 by full welding.

[0105] With the above configuration, the connecting rod 22 can provide support between the two sets of node structures 21, thereby improving the structural strength of the connection between the front frame 111 and the rear frame 112. In addition, the connecting rod 22 is fully welded to the two sets of node structures 21, thereby improving the connection strength between the connecting rod 22 and the node structures 21, and further improving the connection strength between the front frame 111 and the rear frame 112.

[0106] like Figure 16 As shown, in this embodiment, the motorcycle 100 includes a fuel tank 23 and a rear shock absorber 24. The connecting rod 22 can also connect the fuel tank 23 and the rear shock absorber 24.

[0107] Specifically, a sheet metal part 221 is welded onto the connecting rod 22, which can support and connect to the fuel tank 23.

[0108] Specifically, a fixing structure 222 is provided below the connecting rod 22, and the fixing structure 222 is connected to the rear shock absorber 24.

[0109] With the above configuration, the mounting point for the fuel tank 23 and the rear shock absorber 24 can be integrated into the connecting rod 22, thereby simplifying the mounting structure of the fuel tank 23 and the rear shock absorber 24 and improving the structural compactness of the frame 11.

[0110] like Figure 13As shown, the node structure 21 includes a mounting portion 216 connected to the body panel 12. The mounting portion 216 is connected to one side of the main body 211 along the width direction of the frame 11. With the above arrangement, the mounting portion 216 can be provided to protrude from the frame 11, which facilitates the connection between the body panel 12 and the mounting portion 216, thereby facilitating the installation and removal of the body panel 12 on the frame 11.

[0111] In this application, the main body 211 has a tubular structure, and its centerline is substantially parallel to the width direction of the frame 11. The main body 211 includes a front outer side wall and a rear outer side wall. The first connecting rib 214 and the second connecting rib 215 are both connected to the front outer side wall, and the through part 212 is connected to the rear outer side wall. With the above arrangement, the main body 211 is substantially perpendicular to the rear frame 112, thereby improving the structural strength of the node structure 21 connecting the front frame 111 and the rear frame 112, which helps to improve the stability of the connection between the front frame 111 and the rear frame 112, and thus improves the structural strength of the frame 11.

[0112] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A motorcycle, comprising: A vehicle frame, comprising a fixedly connected front frame and a rear frame; A body panel that at least partially covers the front frame and the rear frame; A walking system including front wheels and rear wheels, the front wheels being at least partially located under the front frame and the rear wheels being at least partially located under the rear frame; A power system, comprising an engine and an exhaust pipe, wherein the engine is supported by the front frame and provides power to the rear wheels, and the engine is provided with an exhaust port connected to the exhaust pipe; Its features are, An engine housing is formed within the front frame, and the engine is installed within the engine housing. The front frame includes a front connecting frame located in front of the engine housing. The front connecting frame includes an upper frame rod and two lower frame rods, with the upper ends of the two lower frame rods fixed to the upper frame rod. Viewed from front to back, the two lower frame rods are located on the left and right sides of the exhaust port, respectively, and the exhaust pipe passes between the two lower frame rods along the length of the frame.

2. The motorcycle according to claim 1, characterized in that, The wheelbase of the motorcycle ranges from 1270mm to 1560mm. The connection between the upper frame rod and the two lower frame rods is defined as the fork. The minimum distance between the uppermost point of the exhaust port and the midpoint of the fork along its own height direction along the height direction of the frame ranges from 50mm to 80mm.

3. The motorcycle according to claim 2, characterized in that, Define a reference plane that is perpendicular to the height direction of the frame and passes through the lowest point of the front wheel. The minimum distance between the midpoint of the fork portion along its own height direction and the reference plane is 600mm to 700mm.

4. The motorcycle according to claim 1 or 2, characterized in that, The front frame includes a front lower frame, which is located below the engine housing space and is connected to the lower end of the lower frame rod. The front lower frame includes at least one set of front lower tubes, each set of front lower tubes including multiple straight beams and at least one bent portion. The straight beams and the bent portions are arranged alternately from front to back, and the straight beams and the bent portions form the boundary of the engine housing space. The front end of the straight beam is not lower than its rear end, and the front end of the bent portion is higher than its rear end.

5. The motorcycle according to claim 4, characterized in that, The bending section is provided with at least two parts, including a first bending section and a second bending section. The first bending section is located in front of the second bending section. The straight beam section includes a first straight beam section and a second straight beam section. The first straight beam section is located in front of the second straight beam section. The first bending section is connected between the lower frame rod and the first straight beam section, and the second bending section is connected between the first straight beam section and the second straight beam section.

6. The motorcycle according to claim 4, characterized in that, The front lower frame includes two sets of front lower tubes, which are arranged along the width of the frame. The front lower frame also includes a shock-absorbing crossbeam, with two front lower tubes fixedly connected to both ends of the shock-absorbing crossbeam. The engine is supported by and connected to the front lower tubes.

7. The motorcycle according to claim 6, characterized in that, The front lower frame is fixed with a front mounting component and a rear mounting component. The engine is mounted on the front mounting component and the rear mounting component. Along the length of the frame, the shock-absorbing crossbeam is located between the front mounting component and the rear mounting component.

8. The motorcycle according to claim 7, characterized in that, The front frame also includes a rear connecting frame, which is located behind the engine housing and connected to the rear frame. A positioning connector is connected to the rear connecting frame and is connected to the engine to limit the position of the engine within the engine housing along the length of the frame. The power system also includes a first bolt and at least two second bolts. The first bolt has a larger diameter than the second bolts. The first bolt is used to connect the positioning connector to the engine. A portion of the second bolts is used to connect the front mounting to the engine, and another portion of the second bolts is used to connect the rear mounting to the engine.

9. The motorcycle according to claim 2, characterized in that, The front frame includes a side support beam and a front upper frame. The front upper frame is located above the engine housing space. The front end of the side support beam is connected to the front connecting frame, and the rear end of the side support beam is connected to the front upper frame. The connection point between the side support beam and the front connecting frame is defined as the connection part, and the connection part is located above the fork. Along the height direction of the frame, the minimum distance between the lowest point of the connection part and the midpoint of the fork along its own height direction ranges from 100mm to 140mm.

10. The motorcycle according to claim 1, characterized in that, The motorcycle also includes a radiator, a first heat dissipation connector is installed on the lower frame rod, a second heat dissipation connector is installed on the upper frame rod, the radiator is installed on the two lower frame rods through the first heat dissipation connector, and the radiator is also installed on the upper frame rod through the second heat dissipation connector.