FIELD OF INVENTION

The present invention generally relates to a frame structure for a motorcycle and more particularly to a modified frame for compact packaging of the different motorcycle embodiments.

BACKGROUND OF THE INVENTION

In current market of motorcycles, demand for larger displacement engines (larger cubic capacity) in motorcycles is increasing. Use of larger displacement engines in existing frame base of motorcycles is an issue in terms of packaging as well as serviceability of these engines.

Further, larger displacement engines, power required for transmission system of the engine also increases. In order to provide required power to this larger displacement engines size of the battery has to be increased to provide sufficient power to starter motor to start these engines.

Also, with increasing demand for high engine power as well as improved fuel economy of the motorcycle, there is a need to increase the volume of the air filter.

Hence there is a need to overcome the above challenges by providing a compact frame layout for larger displacement engines without comprising on performance and serviceability requirements.

SUMMARY OF THE INVENTION

Main objective of present invention is to provide a modified frame which facilitate better packaging and ease in serviceability of components like engine, air cleaner and battery for a higher cc motorcycle. Said frame has a front frame member and a rear frame member. Said front frame member has a head tube, an upper front tube and a lower front tube. Rear frame member ha$ at least one upper rear tube and atleast one lower rear tube.

Said Upper front tube has a primary rearward extension and a downward extension and said upper front tube extends in rearward direction from upper end of the head tube. Mentioned lower front tube extends in ani inclined rearward direction from lower end of the head tube. Said upper rear tube has a secondary rearward extension from the primary rearward extension of front frame member. Stated lower rear tube of the rear frame member has a rear: upward extension extending in upward rearward direction from the lower part of the downward extension of the front frame member.

Further, a bridge tube connects rear part of the primary rearward extension and front end of the lower front tube. Said bridge tube is mounted such that front end of the bridge tube is fixed in the proximity of a first joint of the head tube and lower front tube. Rear end of said bridge tube is fixed in the proximity of a second joint of the primary rearward extension and the upper rear tube.

Further, the primary rearward extension and the downward extension are connected at said second joint such that said second joint is forming an arc. Radius of this arc will lie between 140mm to 160mm.

In claimed modified frame, said secondary rearward extension is followed by a secondary rearward upwardly extension. Rear end of the rear upward extension is further fixed with the secondary rearward upwardly extension and forms a curve in the proximity of a third joint between the secondary rearward extension and the secondary rearward upwardly extension. Said curve is formed behind the mounting space of the rear suspension mounting arrangement. Further, for improved engine mounting arrangement atleast one set split mounting bracket is integrated with lower ends of the downward extension and the lower front tube. This split mounting bracket defines a upper mounting bracket and a lower mounting bracket.

Summary provided above explains the basic features of the invention and does not limit the scope of the invention. Additional detailed information related to the enablement of the invention will be provided in the detailed description and accompanying claims. Scope of the invention shall be based on the claims provided.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawing(s). Provided drawings are incorporated in and constitute embodiments of the invention and illustrates several aspects of the invention and together with a description of the embodiments serve to explain the principles of the invention. Drawings given below are provided to support the description of the invention and are not limiting the scope of the present invention. A brief description of: the drawing is as follows:

Figure 1 shows a typical motorcycle side layout depicting the packaging/ mounting arrangement of different arrangement of embodiments with respect to claimed frame of motorcycle.

Figure 2 provides a side view of the claimed frame structure in order to depict fixing arrangement of main embodiments of the invention.

Figure 3, Figure 4 and Figure 5 are depicting essential embodiments and their arrangement for the front part of the frame of the motorcycle. Figure 6 is describing the characterized embodiments of the rear part of the claimed frame of the motorcycle.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that best enabling arrangements of the invention can be explained through all possible embodiments and examples of it. The invention may have application to all kind of motorcycles.

Referring to Figure 1 shows a side view of a concerned motorcycle in the form of a motorcycle capable to incorporate the present invention.; The motorcycle M comprises a body frame assembly made up of a number of tubes welded together. The motorcycle M has a steerable front wheel Oil and a driven rear wheel 012. The body frame primarily includes a front part F and a rear part R.

A front fork 003 may be connected to the front part F of frame by any known type of suspension system and rotatably carries the front wheel Oil. Front part F of frame defines a head pipe 102 which supports a steering shaft (not shown) disposed inside the head pipe 102. The upper and lower ends of the steering shaft are fixed on an upper bracket and the under bracket. Front part of the frame also defines an upper front tube 103 and a lower front tube 104 which are connected to the head pipe 102.

As shown in Figure 1 and Figure 2, lower front tube 104j extends obliquely downward in front of an engine 015 from the head pipe 102 whereas the upper front tube 103 extends rearward from the head tube 102 thereof. Said upper front tube 103 further extends downwards and make a downward extension 109 which supports rear part of the engine 015.

Referring back to Figure 1, a front fender 004 is provided below the under bracket to avoid the motorcycle and its occupants from being splashed with mud. A fuel tank 005 is disposed above the main tube for storing the (fuel for propelling the motorcycle M. A seat 006 for a driver and a pillion is further provided, with the said seat 006 being placed behind the fuel tank 005 along the rear part R of the frame of motorcycle M.

The rear wheel 012 revolves about a sprocket splined shaft (or central axle) 013. The axle 013 is supported at each end by a swing arm 014, the swing arm in turn pivotally connected to the body frame of the motorcycle M by a rear suspension 010. Generally a motorcycle may use any of the two arrangements for rear suspensions 010, namely dual suspension and mono suspension.

However the present motorcycle is exemplified through ja dual suspension system. The dual suspensions are fixed at their upper ends to the motorcycle frame. Their lower ends are fixed to the swing arm 014.

The anterior portion of the motorcycle placed forward to: the fuel tank 005 comprises of a headlamp assembly, the headlamp assembly further comprising a headlamp 008 and a visor 007 placed forward to a handlebar assembly. The handle bar assembly further comprises of a handle bar 009 extending transversely to the motorcycle and several control switches for various motorcycle operations.

The said motorcycle M is powered by an internal combustion engine (hereinafter "engine") 015 supported by the front part F of the iframe. The engine may be liquid-cooled or air-cooled. Drive force output from!the engine 015 is transmitted to the rear wheel 012 through a transmission system. The transmission system includes a clutch actuated by a clutch lever placed forwardly to one side of the handle bar 009, a gear box and a chain drive.

The transfer of power from the engine to the rear wheel takes place generally by disengaging the clutch by pulling the clutch lever and thereafter manually shifting the gears in the gear box through a foot pedal 016 manually operated by the operator of the motorcycle M.

Referring to Figure 2, Figure 3 and Figure 4, as described, upper front tube 103 has a primary rearward extension 103(a) and a downward extension 109. Said upper front tube 103 is extending in rearward direction 103(a) from upper end of
■ the head tube 102. Lower front tube 104 is extending in rearward direction from
lower end of the head tube 102.

A bridge tube 105 is connecting rear part of the primary rearward extension 103 and front end of the lower front tubel04. The front end of the bridge tube 105 is fixed in the proximity of a first joint Jl of the head tube 102 and lower front tube 104. The rear end of the bridge tube 105 is fixed in the proximity of a second joint J2 of the primary rearward extension 103 and the upper rear tube 106.

Further, the primary rearward extension 103 and the downward extension 109 are connected at said joint J2 such that said second joint J2 is forming an arc 115. For best enablement of the invention radius R of said arc 115 lies between 140mm to 160mm.

Above described arrangement ensures ease in serviceability:of the engine 015. During servicing of engine 015, the cylinder head cover, is removed followed by removal of cylinder head and finally cylinder block is removed. In existing designs (of frames) the bridge tube 105 obstructs the cylinder head and cylinder block from removal, when the engine 015 is assembled on the frame 100.

In claimed invention a modified design for the frame 100 is disclosed, the bridge rube 105 is lifted upwards by mounting a specific location on front and rear part i.e. at first joint Jl and second joint J2.

Also, the curved arc 115 at the joint J2 between primary rearward extension 103a and downward extension 109 is widened thus the space; between the upper front tube 103 and the lower front tube 104 is increased. Due to increase in mounting space for the engine 015, the cylinder head coverj cylinder head and cylinder block can be removed without any obstruction. This reduces the servicing time and effort as well as this modification also considerably improves the torsional stiffness of the frame 100 as surface area of front frame member F increases.

Referring to Figure 5, one or more sets of split mounting brackets (111, 112) are integrated with lower end of the downward extension 109 with which rear part of the engine 015 is supported. Further, one set of split mounting bracket 113 is also fixed with the lower end of the lower front tube 104 supporting front part of the engine 015.

These split mounting brackets 111,112 are collectively |defining a upper mounting bracket 112 and a lower mounting bracket 111 through which rear part of the engine is supported at multiple points e.g. two points/brackets 111, 112. This construction of engine 015 mounting can be defined as a box type construction which improves the rigidity of the engine mounting as well as of the motorcycle. By adopting split brackets for engine mounting, j use of material is reduced to a considerable amount resulting in weight reduction of the mounting arrangement.

Further referring to Figure 2 and Figure 6, rear frame member R has multiple rear upward extensions 106r extending parallely in rearward direction. These rear upward extension 106r defines secondary rearward extensions 106 extending in rearward direction from the primary rearward extension 103a of front frame member F. Mentioned secondary rearward extension 106 dfefines a secondary downwardly rearward extension 114 followed by a secondary |rearward upwardly extension 101.
Said rear frame member R also has multiple lower rear tubes 108r defining an upward extension 108 extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F. Further, the secondary rearward extension 106 is followed by a secondary; rearward upwardly extension 101 such that rear end of the rear upward extension 106r of the rear frame member R is fixed with the a secondary rearward upwardly extension 108r and forms a curve C in the proximity of a third joint J3 between the secondary rearward extension 106 and the secondary rearward upwardly extension 101.

Mentioned third joint J31ies in the proximity or behind the upper part OlOu of a rear suspension system 010 and provide better space and clearance for mounting of other parts of motorcycle M. As described above, the upward extension 108 of the rearward upwardly extension 108r is fixed with the secondary rearward upwardly extension 101 towards the end at location 110.

Due to claimed arrangement of the embodiments of the frame of the motorcycle, the available mounting space between the rearward upwardly extension 108r and rear upward extension 106r increases. This mounting space facilitates better packaging of an air cleaner with more volume (a requirement for higher cc Motorcycle) in terms of mounting and serviceability. Further, as the stator motor requires more cranking torque I to start the engine thus required battery capacity is more in order to supply sufficient power to starter motor. With increase in capacity of the battery size of battery also increase and the frame claimed in present invention provides more space for mounting of different battery size as per the requirement of engine capacity of the motorcycle.

WHAT IS CLAIMED IS

1) A frame 100 for a motorcycle M comprising:
a front frame member F having a head tube 102 , an upper front tube 103a defining a primary rearward extension 103 and a downward extension 109 such that said upper front tube 103a is extending in rearward direction from upper end of the head tube 102 and a lower front tube 104 is extending in a inclined rearward direction from lower end of the head tube 102;

a rear frame member R having at least one upper rear tube 106r defining a secondary rearward extension 106 from the primary rearward extension 103 of front frame member F, and atleast one lower rear tube 108r defining a rear upward extensionlOS extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F;

characterized in that a bridge tube 105 is connecting rear part of the primary rearward extension 103 and front end of the lower front tubel04 such that front end of the bridge tube 105 is fixed in the proximity of a first joint Jl of the head tube 102 and lower front tube 104 and wherein rear end of the bridge tube 105 is fixed in the proximity of a second joint J2 of the primary rearward extension 103 and the upper rear tube 106;

the primary rearward extension 103 and the downward I extension 109 are connected at said joint J2 such that said second joint J2 is forming an arc 115 such that arc radius R lies between 140mm to 160mm;

the secondary rearward extension 106 is followed by a Secondary rearward upwardly extension 101 such that rear end of the rear upward extension 106r of the rear frame member R is fixed with the a secondary rearward upwardly extension 108r and forms a curve C in the proximity of a third joint J3 between the secondary rearward extension 106 and the secondary rearward upwardly extension 101; and atleast one set split mounting bracket 113/111 for an engine 015 is integrated with lower ends of the downward extension 109 and the lower front tube 104 such that said split mounting bracket 113/111 is defining a upper mounting bracket 112 and a lower mounting bracket 111.

The frame, as claimed in claim 1, wherein the third joint J3 lies in the proximity of upper part of a rear suspension system OlOu.
A frame 100 for a motorcycle M comprising:

a front frame member F having a head tube 102 , an upper front tube 103a defining a primary rearward extension 103 and a downward extension 109 such that said upper front tube 103a is extending in rearward direction from upper end of the head tube 102 and a lower front tube 104 is extending in a inclined rearward direction from lower end of the head tube 102;

a rear frame member R having at least one upper rear tube 106r defining a secondary rearward extension 106 from the primary rearward extension 103 of front frame member F, and atleast one lower rear tube 108r defining a rear upward extensionl08 extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F;

characterized in that a bridge tube 105 is connecting rear part of the primary rearward extension 103 and front end of the lower front tubel04 such that front end of the bridge tube 105 is fixed in the proximity of a first joint Jl of the head tube 102 and lower front tube 104 and wherein rear end of thelbridge tube 105 is fixed in the proximity of a second joint J2 of the primary rearward extension 103 and the upper rear tube 106.

4) A frame 100 for a motorcycle M comprising:
a front frame member F having a head tube 102 , an upper front tube 103a defining a primary rearward extension 103 and a downward extension 109 such that said upper front tube 103a is extending in rearward direction from upper end of the head tube 102 and a lower front tube 104 is extending in a inclined rearward direction from lower end of the head tube 102;

a rear frame member R having at least one upper rear tube 106r defining a secondary rearward extension 106 from the primary rearward extension 103 of front frame member F, and atleast one lower rear tube 108r defining a rear upward extensionl08 extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F;

characterized in that the primary rearward extension 103: and the downward extension 109 are connected at said joint J2 such that said: second joint J2 is forming an arc 115 such that arc radius R lies between 140mmlto 160mm.

5) A frame 100 for a motorcycle M comprising:
a) a front frame member F having a head tube 102 , an upper front tube 103a defining a primary rearward extension 103 and a downward extension 109 such that said upper front tube 103a is extending in rearward direction from upper end
of the head tube 102 and a lower front tube 104 is extending in a inclined rearward direction from lower end of the head tube 102;
b) a rear frame member R having at least one upper rear tube 106r defining a secondary rearward extension 106 from the primary rearward extension 103 of front frame member F, and atleast one lower rear tube 108r defining a rear upward extensionlOS extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F;
characterized in that the secondary rearward extension 106 is followed by a secondary rearward upwardly extension 101 such that rear end| of the rear upward extension 106r of the rear frame member R is fixed with the a secondary rearward upwardly extension 108r and forms a curve C in the proximity of a third joint J3 between the secondary rearward extension 106 and the secondary rearward upwardly extension 101.
The frame, as claimed in claim 5, wherein the third joint J3 lies in the proximity of upper part of a rear suspension system OlOu.
A frame 100 for a motorcycle M comprising:

a front frame member F having a head tube 102 , an upper front tube 103a defining a primary rearward extension 103 and a downward extension 109 such that said upper front tube 103a is extending in rearward direction from upper end of the head tube 102 and a lower front tube 104 is extending in a inclined rearward direction from lower end of the head tube 102;
a rear frame member R having at least one upper rear tube 106r defining a secondary rearward extension 106 from the primary rearward extension 103 of
front frame member F, and atleast one lower rear tube 108r defining a rear upward extensionl08 extending in upwardly rearward direction from the lower part of the downward extension 109 of the front frame member F;
characterized in that atleast one set split mounting bracket 113/111 for an engine 015 is integrated with lower ends of the downward extension 109 and the lower front tube 104 such that said split mounting bracket 113/111 is defining a upper mounting bracket 112 and a lower mounting bracket 111.1