TECHNICAL FIELD
[0001] The present subject matter generally relates to a footrest assembly, and
more particularly to mounting of a footrest assembly.
BACKGROUND
[0002] Generally, in a two-wheeled vehicle a body frame extends rearward
from a head tube. The body frame acts as a skeleton for the vehicle that supports the vehicle loads. A front portion of the body frame connects a front wheel through one or more front suspension(s). Further, the body frame extends towards a rear portion of the vehicle. A rear wheel is connected to a mainframe assembly through one or more rear suspension(s). An engine assembly is mounted to the mainframe assembly of the vehicle. The engine assembly is functionally connected to the rear wheel, which provides the forward motion to the vehicle. Typically, plurality of panels is mounted to the mainframe assembly of the vehicle that covers various vehicle parts mounted thereon.
[0003] In addition to it, the vehicle comprises of an exhaust emission system
which helps in filtering and releasing of exhaust into the atmosphere being produced by the engine assembly. The exhaust emission system is one of the embodiments most prone to vibrations. Thus, mounting of the exhaust emission system is one of the most critical aspects. Furthermore, the vehicle is also provided with a footrest assembly comprising of rider and pillion footrest used by the rider and pillion to rest his/her foot. Generally, the footrest assembly is mounted on the vehicle body which is typically made of fiber. The vehicle body in such cases is provided with unwanted stress which is not originally intended to.
[0004] Moreover, the previous known arts are provided with numerous
numbers of mountings which only increases the manufacturing cost, number of parts of the vehicle and assembly time. In fact, the vibration level in a vehicle is a function of the number of mountings. Thus, the present subject matter tries to

restrict the vibrations being experienced by the exhaust emission system and reduce the number of mountings attached to the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The detailed description of the present subject matter is described with
reference to the accompanying figures. Same numbers are used throughout the
drawings to reference like features and components.
[0006] Fig. 1 illustrates a left side view of an exemplary two-wheeled saddle
ride-type vehicle, in accordance with an embodiment of the present subject
matter.
[0007] Fig. 2 illustrates a partially enlarged side view of the exemplary
two-wheeled saddle ride-type vehicle as shown in Fig. 1, in accordance with an
embodiment of the present subject matter.
[0008] Fig. 3 illustrates an exploded view of an exhaust emission system and
a pillion footrest in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
[0009] Typically, a two-wheeled vehicle comprises of a frame structure
comprising of a head tube present in a front portion of the vehicle. The frame structure also comprises of a down tube extending in a downward and rearward direction form the head tube, and a main tube extending in a straight and forward direction from the head tube. Generally, a vehicle body surrounds the frame structure to provide an aesthetic appeal and cover the structure. Most of the vehicle parts are mounted onto the vehicle body due to which it has to bear with some extra stress which wasn’t intended to. Parts like footrest assemblies are also mounted onto the vehicle body which enhances the stress factor because of the weight which it bears. The magnitude of the force depends on various factors, for example, the speed of the vehicle, suspension stiffness, wheel mass, body mass, etc. The vehicle structure is not fully rigid. Further, the internal resistance or

stress is induced to balance the external forces. As the stress should be kept within acceptable limits, it is important to note the relation between the factors which play a crucial role in determining the stress factor of a vehicle. It is to be understood that the result of product of static load and dynamic factor should be less than or equal to the yield stress experienced by the vehicle. Generally, the safety factor against the yield is 1.5. The stress factor analysis is important while handling some components at places of stress concentration, for example, the mounting parts, etc.
[00010] Moreover, the vehicle comprises of an exhaust emission system
disposed at one side of the vehicle. An automobile exhaust system comprises of various components or parts of an automobile engine, which are used for discharging burned gases or steam. It is to be noted that engine vibrations can easily shake the exhaust pipe enough to cause component rattling on impact. Damping of such mentioned vibrations should be done to such an extent so that each component can perform to their maximum extent. The exhaust emission system helps in filtering and releasing the exhaust being generated by internal combustion engine of the vehicle. Generally, vehicles suffer from the negative effects of vibration during movement. Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. More often this vibration is undesirable and results in wastage of energy and creation of unwanted sound, i.e. noise. The vibrations which are observed during the vehicle movement results in making the exhaust components to perform at a level which is very lower than their actual performance level over a period of time. Due to its nature of work the exhaust emission system is highly prone to vibrations. When the vibrations created in a vehicle engine is transferred to the exhaust system frequently, they cause the breakage in the exhaust manifold. Also, there are generally two types of vibrations that can affect the exhaust system, they are firstly, the sonic pressure waves coming from the exhaust ports and secondly, the vibration of the engine itself because of torqueing. When combined together, these vibrations can play a critical role in affecting the performance of the overall system as well as the health of the rider in a negative way. Thus, it is highly critical to keep a check on

the above discussed variables in accounting for vibration levels and also to
control such vibrations to improve the durability of the necessary components.
[00011] Hence, the present subject matter is aimed at reducing such stress
which the vehicle body absorbs. In addition to it, the present subject matter also aims at restricting the vibrations of the exhaust emission systems.
[00012] In an embodiment, a vehicle is provided with a mainframe assembly
used as a skeleton for support. The mainframe assembly comprises of a head tube disposed in a front portion of the vehicle and a down tube extending in a downward and rearward fashion from the head tube. In addition to it, the mainframe assembly also comprises of a main tube extending in a straight rearward direction from the head tube. Furthermore, the mainframe assembly also comprises of a rear sub frame assembly partially connected to the main tube and partially connected to the down tube.
[00013] In an embodiment, a mounting bracket is attached to the rear sub
frame assembly on both the sides. According to an aspect of the invention, the vehicle comprises of an exhaust emission system which is attached to the rear sub frame assembly of the mainframe assembly through the mounting bracket. In another embodiment of the present subject matter the mounting clamp is an intrinsic part of the muffler unit, this further reduces the number of components mounted, as by making the mounting clamp and the muffler unit as a single component, the vibration of the overall exhaust system can be reduced further. Further, in an embodiment the mounting clamp has two open ends and one the open ends is made as an intrinsic part of the mounting bracket. The mounting clamp thus attached directly with the mounting bracket acts as a better support for the muffler unit and reduces the vibration frequency by increasing the overall mass of the mounting bracket. Furthermore, the vehicle also comprises of pillion footrest used by the pillion to support his/her feet, wherein the pillion footrest is also attached to the rear sub frame assembly through the mounting bracket. In an embodiment, the exhaust emission system comprises of a mounting clamp through which the exhaust emission is attached to the mounting bracket. According to another aspect of the invention, the other pillion footrest present on

the other side is also attached to the rear sub frame assembly through the mounting bracket.
[00014] Thus, through the present subject matter the vibrations of the exhaust
emission system is restricted and the number of mountings is reduced as it is provided on the rear sub frame assembly. In addition to it, stress applied on the vehicle body is reduced as the mountings are done on the mainframe assembly which is more strong suitable for it. Moreover, the weight of the pillion transferred to pillion footrest, this acts as a counter weight which further helps in reducing the vibrations. The added weight is suitable to absorb the vibration as because of it the mass increases. Also, the weight of the pillion rider is applied in such a way that it is added near the critical components. Thus, this addition of counter weight coming from the pillion rider is beneficiary as it has good vibration absorption prosperity. Furthermore, this added mass due to the weight also provides stability to the exhaust emission system and reduces its vibrations since mountings for both the parts are same. Lastly, the mounting bracket also helps in absorbing some of the vibrations of the exhaust emission system.
[00015] Arrows provided in the top right corner of each figure depicts
direction with respect to the vehicle, wherein an arrow F denotes front direction, an arrow R indicates rear direction, an arrow Up denotes upward direction, an arrow Dw denotes downward direction, an arrow Lh denotes left direction and an Rh denotes right direction.
[00016] Fig. 1 illustrates a left side view of an exemplary saddle type vehicle
(100), in accordance with an embodiment of the present subject matter. The saddle type vehicle (100) includes a mainframe assembly (105) that extends from a head tube (105A), which is disposed in the front portion of said vehicle (100), towards a rear portion of said saddle type vehicle (100). Said mainframe assembly (105) extends in longitudinal direction F-R of said saddle type vehicle (100). Said mainframe assembly (105) may further comprise a sub-frame formed by a pair of rear tubes (not shown) that extend obliquely rearward from the main

frame. An engine assembly (110) is fixedly mounted to said mainframe assembly (105).
[00017] A front portion of a swing arm (115) is swingably connected to said
mainframe assembly (105) and a rear portion of said swing arm (115) rotatably supports a rear wheel (120). Said rear wheel (120) is functionally coupled to said engine assembly (110) through a transmission system. The transmission system (not shown) includes a chain drive/belt drive, a variable gear ratio system, or an automatic type transmission. A rear fender (125) disposed upwardly of said rear wheel (120) covers at least a portion of said rear wheel (120). Further, said swing arm (115) is coupled to said mainframe assembly (105) through one or more rear suspension(s) (not shown). In the present embodiment, a mono-shock type rear suspension connects said swing arm (115) to said mainframe assembly (105). Similarly, a pair of front forks (130) supports a front wheel (135) and is steerably supported by a head tube (105A). A handlebar assembly (140) is connected to an upper portion of said pair of front forks (130). Further, a front fender (145) covers at least a portion of said front wheel (135) and said front fender (145) is mounted to said front forks (130).
[00018] A fuel tank assembly (150) is mounted to said mainframe assembly
(150) and is disposed rearwardly of said handlebar assembly (140). A seat assembly (155) including a rider seat is disposed rearwardly of said fuel tank assembly (150) and is supported by same mainframe assembly (105). Said seat assembly (155) may include a pillion seat. Further, a pair of rider foot pegs (165) mounted to said mainframe assembly (105) of said saddle type vehicle (100) that enable in supporting rider foot.
[00019] Further, said engine assembly (110) includes an air-fuel supply
system (not shown) that supplies air and fuel to said engine assembly (110). An exhaust pipe (not shown) extends from said engine assembly (110) towards a muffler (not shown) that is disposed adjacently of said rear wheel (120). A Plurality of panels (170) covers at least a portion of said mainframe assembly (105) and one or more vehicle parts.

[00020] Furthermore, said saddle type vehicle (100) includes various
electrical and electronic systems including a starter system (not shown), a headlamp (175), a vehicle control unit, and a tail lamp (180). In addition, said saddle type vehicle (100) includes safety systems including a synchronous braking system (not shown), and an anti-lock braking system.
[00021] Fig. 2 illustrates a partially enlarged side view of said saddle type
vehicle (100) in accordance with an embodiment of the present subject matter. In an embodiment, said mainframe assembly (105) comprises of a down tube extending in a downward and rearward fashion from said head tube. In addition to it, said mainframe assembly (105) also comprises of a main tube extending in a straight rearward direction from said head tube. A holder connects said main tube and said down tube. In an embodiment, a rear sub frame assembly (105D) is partially attached to said down tube and said main tube. In an embodiment, a mounting bracket (210) is attached to said rear sub frame assembly (105D), wherein said mounting bracket (210) extends in at least a straight rearward direction. In an embodiment, said mounting bracket (210) is attached on both the sides. As described earlier, said saddle type vehicle (100) comprises of an exhaust emission system (200) to filter and release the exhaust being generated by said engine assembly (110). In addition to it a pillion footrest (205) is also provided which is used by the pillion to rest his/her feet. In an embodiment, said exhaust emission system (200) and said pillion footrest (205) are both attached to said mounting bracket (210).
[00022] Fig. 3 illustrates an exploded view of said exhaust emission system
(200) and said pillion footrest (205) being attached to said mounting bracket (210) in accordance with an embodiment of the present subject matter. In an embodiment, said exhaust emission system (200) comprises of a muffler unit (305) and an exhaust pipe (310) connected to it. As per the present subject matter,

a mounting clamp (315) is provided through which said exhaust emission system (200) is detachably attached to said mounting bracket (210). Said mounting clamp (315) is detachably attached to said mounting bracket (210), wherein said mounting clamp (315) also holds said exhaust emission system (200), and said muffler unit (305) to be particular. In an embodiment, said pillion footrest (205) is also detachably attached to said mounting bracket (210). Said pillion footrest (205) is also attached to said mounting bracket (210) through a holder (320). Thus, said exhaust emission system (200) and said pillion footrest (205) are mounted on said mounting bracket (210). Further, said pillion footrest (205) is disposed in a way such that it acts as a support for the foot of the pillion rider. Also, said pillion footrest (205) prevents the pillion rider’s leg from touching the wheel thereby reduces the chance of occurrence of an accident. Through such a system the number of mountings is reduced and the vibrations and stress is directly transferred by shifting the transmissibility path of the inertial effect on said muffler unit (305) to said rear sub frame assembly (105D) without providing a direct load to the vehicle body. It is known that the vibration frequency is inversely proportional to the mass applied on the component and hence, the added weight on said pillion footrest (205) has a tendency to shift the frequency of vibration towards lower ranges. In addition to it, the extra weight applied on said pillion footrest (205) also helps in controlling the vibrations of said exhaust emission system (200) since both of the elements are attached to said mounting bracket (210). The higher the area of contacts higher will be the chances of vibration; hence by providing said mounting clamp (315) and said holder (320) the contact area is reduced. Also, this reduction in the number of mounting components further makes the overall structure of said mounting bracket (210) more rigid and hence, less prone to vibration.
[00023] Thus, the present subject matter present a common member
mounting for said exhaust emission system (200) and said pillion footrest (205), wherein both the elements are mounted on said mounting bracket (210) attached to said rear sub frame assembly (105D). Thus, through such a system vibrations

of said exhaust emission system (200) are restricted and the numbers of mountings are reduced. In furtherance to it, the stress is transferred to said mainframe assembly (105) and not the vehicle body (made of fiber). In fact, the weight applied on said pillion footrest (205) is also transferred on said exhaust emission system (200) which further helps in controlling its vibrations. The weight applied by the pillion rider on said pillion footrest (205) acts as a counter weight which further helps in reducing the vibrations. The added weight is suitable to absorb the vibration by increasing the mass. Also, the weight of the pillion rider is applied in such a way that it is added near the critical components on said mounting bracket (210) on which said pillion footrest (205) is mounted. This further improves said pillion footrest (205) anti-vibration performance.
[00024] It is to be understood that the aspects of the embodiments are not
necessarily limited to the features described herein. Many modifications and variations of the present subject matter are possible in the light of above disclosure.

List of Reference Signs
100 saddle type vehicle 200 Exhaust emission system
105 Mainframe assembly 205 Pillion footrest
105A Head tube 210 Mounting bracket
105B Down tube 305 Muffler unit
105C Main tube 310 Exhaust pipe
105D Rear sub frame assembly 315 Mounting clamp
110 Engine assembly 320 Holder
115 Swing arm
120 Rear wheel
125 Rear fender
130 Front forks
135 Front wheel
140 Handlebar assembly
145 Front fender
150 Mainframe assembly
155 Seat assembly
165 Rider foot pegs
170 Panels
175 Headlamp
180 Tail lamp

We Claim:
1. A saddle type vehicle (100) comprising:
a mainframe assembly (105) comprising the head tube present in the front portion of said vehicle (100), the down tube extending in a downward and rearward fashion from the head tube, the main tube extending in a substantially straight and rearward direction from the head tube, and a rear sub frame assembly (105D) partially attached to the main tube and the down tube at a rear portion of said vehicle (100);
a mounting bracket (210) is attached to said rear sub frame assembly (105D), wherein said mounting bracket (210) extends in at least a rearward direction from said rear sub frame assembly (105D);
an exhaust emission system (200) is detachably attached to said mounting bracket (210); and
a pillion footrest assembly (205) is detachably attached to said mounting bracket (210).
2. The saddle type vehicle (100) as claimed in Claim 1, wherein said exhaust emission system (200) includes a muffler unit (305) detachably attached to said mounting bracket (210) of said rear sub frame assembly (105D) through a mounting clamp (315).
3. The saddle type vehicle (100) as claimed in Claim 1, wherein said pillion footrest assembly (205) is detachably attached to said mounting bracket (210) of said rear sub frame assembly (105D) via a holder (320).
4. The saddle type vehicle (100) as claimed in Claim 1, wherein said pillion footrest assembly (205) is integrated with said rear sub frame assembly (105D) via a holder (320).

5. The saddle type vehicle (100) as claimed in Claim 1, wherein said mounting clamp (315) is integrated with said muffler unit (305).
6. The saddle type vehicle (100) as claimed in Claim 1, wherein said mounting clamp (315) is integrated with said mounting bracket (210).
7. The saddle type vehicle (100) as claimed in Claim 6, wherein said mounting clamp (315) has at least one of the ends open.