WO2021161336A1

WO2021161336A1 - Frame assembly of vehicle

Info

Publication number: WO2021161336A1
Application number: PCT/IN2021/050127
Authority: WO
Inventors: Rajat Bhardwaj; Anuj Jain; Ankit Agarwal; Gaurav DADHEECH; Satyendra Dhar DWIVEDI
Original assignee: Hero MotoCorp Limited
Priority date: 2020-02-10
Filing date: 2021-02-10
Publication date: 2021-08-19

Abstract

The present disclosure relates to a two-wheeled vehicle (10). The vehicle (10) having a body frame (106) comprising a head tube (122), a down frame (500) extending rearward and downward from the head tube (122). The at least portion of the down frame (500) comprises a first plate member (508) and a second plate member (510) being interconnected with each other. The down frame (500) extends between the head tube (122) and the first cross member (126).

Description

“FRAME ASSEMBLY OF VEHICLE”

TECHNICAL FIELD

[0001] The present disclosure relates to the field of automobiles. Specifically, the present disclosure relates to a body frame of a two-wheeled vehicle.

BACKGROUND [0002] Vehicles, such as, but not limited to, motorized scooter, motorcycle etc., have a plurality of components and assemblies, such as a body frame, a power unit, a set of ground engaging members. The power unit is adapted to provide the necessary power to the ground engaging members, to drive the vehicle. The power unit is carried by the body frame. The ground engaging members are connected to the body frame. Therefore, the body frame is designed to carry a load of the vehicle, including the weight of the power unit, other components, and sub-assemblies of the vehicle. Such weight carried by the body frame is transferred, through the ground engaging members, to the ground.

[0003] However, in addition to the weight of the power unit, other components, and sub-assemblies of the vehicle, the body frame is also required to hold and sustain loads of occupants of the vehicle, attachments to the vehicle, and articles carried by the vehicle. In addition, the effect of these loads on the vehicle often appears more detrimental or demanding for the body frame, when the vehicle is operational, for example at a higher speed or on an undulated surface. Therefore, it is often seen that few body frames get damaged during usage thereof, owing to the limitations associated with handling and managing the loads applied thereon.

[0004] Thus, a major limitation in the conventional body frames of the vehicle is its strength and therefore the rigidity of the body frame itself must be enhanced to thereby enhance the supporting rigidity of the sub-assemblies of the vehicle. [0005] The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the prior art.

SUMMARY

[0006] The present disclosure provides a two-wheeled vehicle in which the rigidity of a body frame is enhanced by providing a down frame extending rearward and downward from a head tube. The disclosed down frame can be utilized to support the sub-assemblies of the vehicle, without affecting the rigidity of the vehicle.

[0007] In an aspect the vehicle has the body frame comprising the head tube, the down frame extending rearward and downward from the head tube. The at least portion of the down frame comprises a first plate member and a second plate member being interconnected with each other.

[0008] In an aspect, the down frame comprises a main down tube, a first down tube and a second down tube. The down frame extending between the head tube and a first cross member of the body frame. [0009] In an aspect, the first down tube and the second down tube extends from one of the main down tube or the down frame.

[00010] In an aspect, the first down tube comprises a vertical portion, a curved portion, and a horizontal portion. The curved portion connects the vertical portion with the horizontal portion, such that the vertical portion is at a predefined angle with respect to the horizontal portion.

[00011] In an aspect, the down frame comprises a top connecting plate connected to the first plate member, and a bottom connecting plate connected to the second plate member. The top connecting plate is connected to a top portion of the head tube, and the bottom connecting plate is connected to a bottom portion of the head tube. [00012] In an aspect, the first plate member comprises a vertical plate connected to the top connecting plate, a horizontal plate connected to the first cross member, and a tilted plate connecting the vertical plate with the horizontal plate.

[00013] In an aspect, the second plate member comprises a vertical plate connected to the bottom connecting plate, a horizontal plate connected to the first cross member, and a tilted plate connecting the vertical plate with the horizontal plate.

[00014] In an aspect, the two-wheeled vehicle comprises a leg shield, wherein at least a portion of the head tube and the down frame is enclosed by at least a portion of the leg shield.

[00015] In an aspect, the down frame comprises a left plate member, and a right plate member. The first plate member, the second plate member, the left plate member, and the right plate member are interconnected to one another.

[00016] In an aspect, the main down tube extends between the top connecting plate and the bottom connecting plate.

[00017] In an aspect, the main down tube extends beyond the bottom connecting plate.

[00018] In an aspect, the main down tube extends till the first cross member.

[00019] In an aspect, the main down tube is connected to a back side of the head tube.

[00020] In an aspect, the vertical portion of the first down tube is connected to the left plate member and the vertical portion of the second down tube is connected to the right plate member.

[00021] In an aspect, the top portion of the main down tube is connected to the back side of the head tube and the bottom portion is positioned downwardly and below the top portion such that the bottom portion remains concealed behind the first plate member and the second plate member.

[00022] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF DRAWINGS

[00023] The disclosure itself, together with further features and attended advantages, will become apparent from consideration of the following detailed description, taken in conjunction with the accompanying drawings. One or more embodiments of the present disclosure are now described, by way of example only wherein like reference numerals represent like elements and in which:

[00024] Figure 1 illustrates a side view of an exemplary two-wheeled vehicle, according to an embodiment of the present disclosure;

[00025] Figure 2 illustrates a side view of a body frame of the vehicle of figure 1, according to an embodiment of the present disclosure;

[00026] Figure 3 illustrates a perspective view of the body frame of the vehicle of figure 1, according to an embodiment of the present disclosure; [00027] Figure 4 illustrates a front view of the body frame of the vehicle of figure 1, according to an embodiment of the present disclosure;

[00028] Figures 5 illustrates a bottom view of the body frame of the vehicle of figure 1, according to an embodiment of the present disclosure; and [00029] Figures 6 illustrates another perspective view of the body frame of the vehicle, according to an embodiment of the present disclosure.

[00030] The drawings referred to in this description are not to be understood as being drawn to scale except if specifically noted, and such drawings are only exemplary in nature.

DETAILED DESCRIPTION

[00031] While the invention is susceptible to various modifications and alternative forms, an embodiment thereof has been shown by way of example in the drawings and will be described here below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and the scope of the invention.

[00032] The term “comprises”, comprising, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, structure or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or structure or method. In other words, one or more elements in a system or apparatus proceeded by “comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.

[00033] For a better understanding of this disclosure, a reference would now be made to the embodiment illustrated in the accompanying Figures and description here below, further, in the following Figures, the same reference numerals are used to identify the same components in various views. [00034] While the present disclosure is illustrated in the context of a vehicle, however, frame assembly and aspects and features thereof can be used with other type of vehicles as well. The terms “vehicle”, “two-wheeled vehicle”, “electric vehicle”, “EV” and “motorcycle” have been interchangeably used throughout the description. The term “vehicle” comprises vehicles such as motorcycles, scooters, bicycles, mopeds, scooter type vehicle, and the like.

[00035] The terms “front / forward”, “rear / rearward / back / backward”, “up / upper / top”, “down / lower / lower ward / downward, bottom”, “left / leftward”, “right / rightward” used therein represents the directions as seen from a vehicle driver sitting astride and these directions are referred by arrows Fr, Rr, U, Lr, L, R in the drawing Figures.

[00036] Referring to Figure 1, an exemplary vehicle (10) according to an embodiment of the present disclosure is illustrated. The vehicle (10) referred to herein, embodies a step-through type vehicle. Alternatively, the vehicle (10) may embody any other ridden vehicle such as an electric motorcycle, etc. without limiting the scope of the invention.

[00037] Referring to Figure 1, the vehicle comprises a front end structure (102), a floorboard (134), a power unit, and a rear end structure (104). The front end structure (102) comprises a steering mechanism (113), a leg shield (108), a front ground engaging member (110), a dash assembly (116), a control unit (not shown), a headlamp unit (118), and a plurality of winkers (120). The steering mechanism (113) comprises a handlebar (114). The handlebar (114) is configured to be rotated by the rider to steer the vehicle (10). The steering mechanism (113) comprises a plurality of front forks (136) disposed at the front portion of the vehicle (10). The steering mechanism (113) is operatively coupled to the front ground engaging member (110) via the plurality of front forks (136). The control unit controls various operations of the vehicle (10).

[00038] In the illustrated example, the dash assembly (116) is provided on the steering mechanism (113). The dash assembly (116) comprises a display unit (not shown). The display unit displays information relating to the vehicle (10) to the rider. In an embodiment, the display unit displays information such as state of charge in the battery, distance travelled by the vehicle (10), and other operating parameters of the vehicle (10). The dash assembly (116) may comprise additional components such as LCD, GPS, graphical user interface (GUI) etc. without limiting the scope of the invention. In the illustrated example, the headlamp unit (114) is provided on the steering mechanism (113). Alternatively, the headlamp unit (114) may be provided on the leg shield (108), without limiting the scope of the invention.

[00039] Further, the front end structure (102) comprises first electronic connections (not shown) and first hydraulic connections (not shown). The first electronic connections may embody a wire harness. The first hydraulic connections may embody fluid hoses. Further, the front end structure (102) may further comprise additional components such as mirrors, front fenders etc. without limiting the scope of the disclosure.

[00040] The leg shield (108) is disposed on the front portion of the vehicle (10). The leg shield (108) encloses the steering mechanism (113). The leg shield (108) comprises an inner leg shield (109) and an outer leg shield (111). The leg shield (108) provides protection for the feet of the rider of the vehicle (10). In the illustrated example, the plurality of the winkers (120) are disposed on the leg shield (108). Alternatively, the plurality of the winkers (120) may be provided on the steering mechanism (113) of the vehicle (10), without any limitations. The floorboard (134) is disposed behind the front end structure (102) and the rear end structure (104). The floorboard (134) provides a footrest for a rider riding the vehicle (10).

[00041] Referring now to Figure 2, Figure 3, Figure 4, Figure 5, and Figure 6, illustrating various views of a body frame (106) of the vehicle (10). The body frame (106) comprises a head tube (122), a down frame (500), a first cross member (126), a left seat rail (128), and a right seat rail (130).

[00042] The steering mechanism ( 113) is pivotally supported on the body frame (106). More particularly, the head tube (122) supports the steering mechanism (113). Further, at least a portion of the head tube (122) and the down frame (500) is enclosed by at least a portion of the leg shield (108). As illustrated in Figure 1, the vehicle (10) comprises a passenger’s seat (170). The rider’s seat (112) and the passenger’s seat (170) are disposed on the left seat rail (128) and the right seat rail (130). The rider’s seat (112) and the passenger seat (170) may be formed as a single unit or may be individual members, without any limitations. The vehicle (10) comprises the control unit (not shown). The control unit controls various operations of the vehicle (10).

[00043] Referring to Figures 1, the vehicle (10) comprises a front side cover (141), a left side cover (142), and a right side cover (not shown). The front side cover (141) is disposed adjacent to the floorboard (134) and covers the front area below the rider’s seat (112). The left side cover (142) and the right side cover (not shown) are disposed on both sides of the vehicle body and cover the lower sides of the rider’s seat (112) and the passenger’s seat (170).

[00044] Further, the vehicle (10) may also comprise a first battery unit (not shown). In an embodiment, the first battery unit may be disposed below the left seat rail (128) and the right seat rail (130). In one example, the first battery unit may be disposed within the leg shield (108). In another example, the first battery unit is disposed underneath the floorboard (134), without limiting the scope of the invention. The first battery unit is electrically coupled to the control unit and the power unit and provides necessary power if and when required.

[00045] Referring to Figures 1, the vehicle (10) comprises the rear end structure (104). The rear end structure (104) is disposed at the rear portion of the vehicle (10). The rear end structure (106) comprises a swing arm (160), a tail lamp (182) and a rear side cover (188). The rear side cover (188) is disposed on the rear portion of the vehicle (10) and covers a hind area below the passenger’s seat (170). In the illustrated example, the tail lamp (182) is disposed on the rear side cover (188). A plurality of turn signal indicators (183) are disposed on either side of the tail lamp (182). [00046] The rear end structure (104) comprises a rear ground engaging member (184), a second battery unit (not shown), and at least one suspension device (502). In the illustrated example, the rear ground engaging member (184) is disposed below the rider’s seat (112) and the passenger’s seat (170). The second battery unit (not shown) stores the energy required to power the power unit. The second battery unit is electrically coupled to the power unit via the control unit of the front end structure (102). The first battery unit is electrically coupled to the control unit and the power unit and provides necessary power if and when required.

[00047] The rear end structure (104) comprises at least one suspension device (502). In the illustrated example, the rear end structure (104) comprises one suspension device (502) which is operatively coupled between the body frame (106) and the swing arm (160). The suspension device (502) embodies a shock absorber. The rear end structure (104) may comprise additional components such as rear grip, rear fender, license plate etc. without limiting the scope of the invention. [00048] The rear end structure (104) comprises second electronic connections

(not shown) and second hydraulic connections (not shown). The second electronic connections may embody a wire harness. The second hydraulic connections may embody fluid hoses. The first electronic connections and the second electronic connections are detachably coupled to one another. The first hydraulic connections and the second hydraulic connections are detachably coupled to one another.

[00049] In the illustrated example, the swing arm (160) is pivotally coupled to the body frame (106). More particularly, a first member (162) of the swing arm (160) is pivotally coupled to the body frame (106). The rear ground engaging member ( 184) is rotatably supported on a second member (164). The second member (164) is detachably coupled to the first member (162) of the swing arm.

[00050] Referring again to Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6, showing the body frame (106) of the vehicle (10). The down frame (500) extends in a rearward and downward direction from the head tube (122). The down frame (500) extends between the head tube (122) and the first cross member (126).

[00051] The down frame (500) comprises a top connecting plate (504), and a bottom connecting plate (506). Each of the top connecting plate (504), and the bottom connecting plate (506) is connected to the head tube (122). In particular, the top connecting plate (504) is connected to a top portion (not numbered) of the head tube (122), whereas the bottom connecting plate (506) is connected to a bottom portion (not numbered) of the head tube (122). As illustrated, the top connecting plate (504), is adjacent to a top bridge (136a), on which the handlebar (114) is mounted, and the bottom connecting plate (506) is adjacent to a bottom bridge (136b), shown in Figure. 2.

[00052] In an embodiment, the head tube (122), in addition to each of the top connecting plate (504), and the bottom connecting plate (506), is adapted to rotatably move with respect to the top bridge (136a) and the bottom bridge (136b).

[00053] The down frame (500) further comprises a first plate member (508), a second plate member (510), a left plate member (512), and a right plate member (514). The right plate member (514), and the left plate member (512) connect the first plate member (508), and the second plate member (510). In addition, the down frame (500) of the body frame (106) includes a main down tube (516), shown in Figure 6, a first down tube (518), and a second down tube (520). In an embodiment, the first plate member (508), the second plate member (510), the left plate member (512), and the right plate member (514), may be integral to one another. Alternatively, the first plate member (508), the second plate member (510), the left plate member (512), and the right plate member (514), may be joined together. In an embodiment, the at least portion of the down frame (500) comprises the first plate member (508) and the second plate member (510) being interconnected with each other.

[00054] Each of the first plate member (508), and the second plate member (510) extend downwardly from the head tube (122). The first plate member (508) is connected to the top connecting plate (504) and extends downwardly. On the other hand, the second plate member (510) is connected to the bottom connecting plate (506). In an embodiment, the bottom connecting plate (506) is connected to each of the first plate member (508), and the second plate member (510).

[00055] The main down tube (516) extends between the top connecting plate (504) and the bottom connecting plate (506). Alternatively, the main down tube (516), while extending between the top connecting plate (504) and the bottom connecting plate (506), is connected to a backside of the head tube (122). In an embodiment, the main down tube (516) extends beyond the bottom connecting plate (506) and till the first cross member (126).

[00056] In an embodiment of the present disclosure, the main down tube (516) includes a top portion (not numbered) connected to the backside of the head tube (122) and a bottom portion (not illustrated) positioned downwardly and below the top portion. The bottom portion remains concealed behind the first plate member (508), and the second plate member (510). In an embodiment, the bottom portion remains concealed behind the first plate member (508), the second plate member (510), the left plate member (512), and the right plate member (514).

[00057] Further, in an embodiment, the bottom portion of the main down tube (516) stems into two pipes namely, the first down tube (518), and the second down tube (520).

[00058] As shown in Figure 3, the first down tube (518) includes a vertical portion (518a), a curved portion (518b), and a horizontal portion (518c). The curved portion (518b) joins the vertical portion (518a) with the horizontal portion (518c). Likewise, the second down tube (520) includes a vertical portion (520a), a curved portion (520b), and a horizontal portion (520c). The curved portion (520b) joins the vertical portion (520a) with the horizontal portion (520c). The first down tube (518), i.e., the vertical portion (518a), the curved portion (518b), and the horizontal portion (518c), extend downward, and then horizontally from a left side of the vehicle (10). Similarly, since the second down tube (520) is identical to the first down tube (518), the second down tube (520), i.e., the vertical portion (520a), the curved portion (520b), and the horizontal portion (520c), extend downward, and then horizontally from a right side of the vehicle (10). [00059] More specifically, the vertical portion (518a) of the first down tube

(518) is connected to the bottom portion of the main down tube (516). Further, the vertical portion (518a) of the first down tube (518) is connected to the left plate member (512). Alternatively, the vertical portion (518a) of the first down tube (518) passes through the left plate member (512), while being connected to the bottom portion of the main down tube (516).

[00060] Likewise, the vertical portion (520a) of the second down tube (520) is connected to the bottom portion of the main down tube (516). Further, the vertical portion (520a) of the second down tube (520) is connected to the right plate member (514). Alternatively, the vertical portion (520a) of the second down tube (520) passes through the right plate member (514), while being connected to the bottom portion of the main down tube (516).

[00061] The horizontal portion (518c) of the first down tube (518) is connected to the first cross member (126). The horizontal portion (518c) of the second down tube (520) is also connected to the first cross member (126). [00062] Referring now to Figure. 5, illustrating a bottom view of the body frame

(106) of the vehicle (10). The second plate member (510) of the down frame (500), further includes a vertical plate (510a), a tilted plate (510b), and a horizontal plate (510c). The vertical plate (510a) is connected to the bottom connecting plate (506). The tilted plate (510b) connects the vertical plate (510a) with the horizontal plate (510c). The horizontal plate (510c) is connected to the first cross member (126). In an embodiment, the horizontal plate (510c) runs parallel to the floorboard (134) of the vehicle (10). Therefore, in an embodiment, the horizontal plate (510c) by being positioned parallel to the floorboard (134) of the vehicle (10), provides support to the floorboard (134) of the vehicle (10).

[00063] Referring now to Figure. 2 and Figure. 3, illustrating a side view and perspective views of the body frame (106) of the vehicle (10). The first plate member (508) of the down frame (500), further includes a substantially vertical plate (508a), a tilted plate (508b), and a horizontal plate (508c). The vertical plate (508a) is connected to the top connecting plate (504). In an embodiment, the vertical plate (508a) is connected to each of the top connecting plate (504) and the bottom connecting plate (506). The tilted plate (508b) connects the vertical plate (508a) with the horizontal plate (508c). The horizontal plate (508c) is connected to the first cross member (126). In an embodiment, the horizontal plate (508c) runs parallel to the floorboard (134) of the vehicle (10). Therefore, in an embodiment, the horizontal plate (510c) by being positioned parallel to, and below the floorboard (134) of the vehicle (10), provides support to the floorboard (134) of the vehicle (10).

[00064] The left seat rail (128) and the right seat rail (130) extend rearward and upward from the first cross member (126). The body frame (106) of the vehicle (10) further includes multiple cross members such as a second cross member (126a), a third cross member (126b), and a fourth cross member (126c). Each of the second cross member (126a), the third cross member (126b), and the fourth cross member (126c) extend parallel to the first cross member (126). Further, each of the second cross member (126a), the third cross member (126b), and the fourth cross member (126c) extend between the left seat rail (128) and the right seat rail (130).

[00065] The present disclosure provides the two- wheeled vehicle (10) in which the rigidity of the body frame (106) is enhanced by providing the down frame (500) extending rearward and downward from the head tube (122). The disclosed down frame (500) can be further utilized to support the sub-assemblies of the vehicle, without affecting the rigidity of the vehicle (10). [00066] While few embodiments of the present disclosure have been described above, it is to be understood that the disclosure is not limited to the above embodiments and modifications may be appropriately made thereto within the spirit and scope of the invention. [00067] While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

Claims

The Claims:

1. A two- wheeled vehicle (10) comprising: a body frame (106) comprising a head tube (122), a down frame (500) extending rearward and downward from the head tube (122); wherein at least portion of the down frame (500) comprises a first plate member (508) and a second plate member (510) being interconnected with each other.

2. The two-wheeled vehicle (10) as claimed in the claim 1, wherein the down frame (500) comprises a main down tube (516), a first down tube (518) and a second down tube (520), the down frame (500) extending between the head tube (122) and a first cross member (126) of the body frame (106).

3. The two-wheeled vehicle (10) as claimed in the claim 2, wherein the first down tube (518) and the second down tube (520) extends from one of the main down tube (516) and the down frame (500).

4. The two-wheeled vehicle (10) as claimed in the claim 2, wherein the first down tube (518) comprises a vertical portion (518a), a curved portion (518b), and a horizontal portion (518c), the curved portion (518b) connects the vertical portion (518a) with the horizontal portion (518c), such that the vertical portion (518a) is at a predefined angle with respect to the horizontal portion (518c).

5. The two-wheeled vehicle (10) as claimed in the claim 2, wherein the second down tube (520) comprises a vertical portion (520a), a curved portion (520b), and a horizontal portion (520c), the curved portion (520b) connects the vertical portion (520a) with the horizontal portion (520c), such that the vertical portion (520a) is at a predefined angle with respect to the horizontal portion (520c).

6. The two-wheeled vehicle (10) as claimed in the claim 1, wherein the down frame (500) comprises a top connecting plate (504) connected to the first plate member (508), and a bottom connecting plate (506) connected to the second plate member (510), the top connecting plate (504) is connected to a top portion of the head tube (122), and the bottom connecting plate (506) is connected to a bottom portion of the head tube (122).

7. The two-wheeled vehicle (10) as claimed in the claims 2 and 6, wherein the first plate member (508) comprises a vertical plate (508a) connected to the top connecting plate (504), a horizontal plate (508c) connected to the first cross member (126), and a tilted plate (508b) connecting the vertical plate (508a) with the horizontal plate (508c).

8. The two-wheeled vehicle (10) as claimed in the claims 2 and 6, wherein the second plate member (510) comprises a vertical plate (510a) connected to the bottom connecting plate (506), a horizontal plate (510c) connected to the first cross member (126), and a tilted plate (510b) connecting the vertical plate (510a) with the horizontal plate (510c).

9. The two-wheeled vehicle (10) as claimed in the claim 1, comprises a leg shield (108), wherein at least a portion of the head tube (122) and the down frame (500) is enclosed by at least a portion of the leg shield (108).

10. The two-wheeled vehicle (10) as claimed in the claim 1, wherein the down frame (500) comprises a left plate member (512), and a right plate member (514), the first plate member (508), the second plate member (510), the left plate member (512), and the right plate member (514) are interconnected to one another.

11. The two-wheeled vehicle (10) as claimed in the claims 2 and 6, wherein the main down tube (516) extends between the top connecting plate (504) and the bottom connecting plate (506).

12. The two-wheeled vehicle (10) as claimed in the claim 11, wherein the main down tube (516) extends beyond the bottom connecting plate (506).

13. The two-wheeled vehicle (10) as claimed in the claim 12, wherein the main down tube (516) extends till the first cross member (126).

14. The two-wheeled vehicle (10) as claimed in claim 13, wherein the main down tube (516) is connected to a back side of the head tube (122).

15. The two-wheeled vehicle (10) as claimed in claim 4 and claim 10, wherein the vertical portion (518a) of the first down tube (518) is connected to the left plate member (512) and the vertical portion (520a) of the second down tube (520) is connected to the right plate member (514).

16. The two-wheeled vehicle (10) as claimed in claim 3 and claim 14, wherein the top portion of the main down tube (516) is connected to the back side of the head tube (122) and the bottom portion is positioned downwardly and below the top portion such that the bottom portion remains concealed behind the first plate member (508) and the second plate member (510).