Patent Publication Number: US-2013249187-A1

Title: Bicycle damping system

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to bicycles. More particularly, the present invention relates to a system configured to reduce vibrations transmitted to a rider of the bicycle. 
     2. Description of the Related Art 
     Bicycle riding and racing often take place on less than ideal terrain conditions. For example, bicycle touring and racing may often take place on country roads, which may be unpaved or where the pavement may be rough and irregular, even when new. In more populated areas, a significant portion of paved roads may be damaged and in need of repair. When traversed by the bicycle, these irregular surfaces transmit vibrations to the bicycle. Furthermore, the surface of even relatively new pavement, while acceptable for motor vehicles, may be rough enough to transmit significant vibration to a bicycle. Accordingly, most bicyclists spend at least a significant portion of their riding time traversing rough or irregular surfaces. Vibrations induced by such terrain, if not sufficiently dampened, may be transmitted to the rider of the bicycle. When transmitted to the rider, these vibrations often cause discomfort and fatigue. 
     Several methods for damping terrain-induced vibrations have been utilized. For example, the bicycle may be equipped with front and/or rear suspension assemblies, which permit the suspended wheel to move against a biasing force relative to the bicycle frame. Although highly favored in some applications, such as bicycles intended primarily for off-road use, such suspension assemblies have generally been unsuccessful in connection with bicycles primarily intended for use on paved surfaces (i.e., road bicycles), where low weight and aerodynamics are considered highly important. Furthermore, such suspension assemblies are intended to absorb large bumps and may not be effective at isolating vibrations due to inherent friction within the assembly, which may prevent movement of the suspension assembly in response to small forces. 
     In road bicycle applications, it has recently become popular to utilize materials having improved damping properties in comparison to metals to form a portion or all of the bicycle between the wheels and the rider. For example, a composite material of carbon fiber fabric within a resin matrix (“carbon fiber”) is often used in an attempt to isolate road-induced vibrations from the rider of the bicycle. In some instances, the entire frame of the bicycle may be comprised of a carbon fiber material. 
     Such an arrangement has been more successful in isolating terrain-induced vibrations from reaching the rider of the bicycle in comparison with bicycle frames and components comprised entirely of metal. However, although carbon fiber is lightweight and exhibits improved vibration damping characteristics in comparison to metal, a significant amount of vibration may nonetheless be transferred through components made from carbon fiber. 
     One proposed solution to carbon fibers undesirable transmission of vibrations is to incorporate an additional material into the carbon fiber fabric that is used to make the final carbon fiber product. For example, a weave of titanium filaments has been incorporated into carbon fiber fabric in an attempt to reduce the amount of vibration that is transmitted through components made of carbon fiber. However, such a solution necessitates a complex manufacturing process and, thus, increases the cost of the final product. 
     SUMMARY OF THE INVENTION 
     Accordingly, a need exists for a cost-effective method of reducing vibrations from being transmitted from the wheels of a bicycle to the rider of the bicycle. Preferred embodiments of a front fork assembly are constructed from a carbon fiber material and include a portion on each leg of the fork assembly, which defines a surface cavity for receiving a separate vibration damping member. Preferably, the vibration damping member is constructed from an elastomeric material and is retained with a plate within the surface cavity of each leg of the front fork. In some embodiments, the surface cavity and/or the damping member can extend along the outer surface of the fork leg from the inner side near a wheel to an outer side away from the wheel. 
     In some embodiments, a bicycle can comprise a main frame portion, a wheel, and a wheel support. The wheel support can be coupled to said main frame portion at a first end to support said wheel at a second end. An outer wall of said wheel support can define a first surface cavity, the first surface cavity extending along the outer wall from a first side to a second side, the second side being an opposing side of the outer wall from the first side. A damping member can be contoured to fit within and be positioned within said first surface cavity, thereby extending along the outer wall between opposing sides of the outer wall. A plate can secure said damping member within said first surface cavity and force said damping member into contact with a surface of said first surface cavity to thereby dampen vibrations introduced to said wheel support by said wheel. 
     According to certain embodiments, one or more of the damping member and the plate can be substantially U-shaped. The plate may cover substantially the entire or less than an entire outer surface of the damping member. The damping member can occupy substantially the entire or less than the entire volume of the first surface cavity. 
     In some embodiments, a bicycle can comprise a main frame portion, a wheel, and a wheel support coupled to said main frame portion at a first end and supporting said wheel at a second end. An outer wall of said wheel support can define a first surface cavity. A damping member can be positioned within said first surface cavity, said damping member extending along the outer wall and engaging opposing sides of the outer wall. A plate can secure said damping member within said first surface cavity, wherein said damping member is configured to be forced into contact with a surface of said first surface cavity to thereby dampen vibrations introduced to said wheel support by said wheel. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects and advantages are described below with reference to the drawings, which are intended to illustrate but not to limit the invention. In the drawings, like reference characters denote corresponding features consistently throughout similar embodiments. 
         FIG. 1  is a side elevation view of a bicycle. 
         FIG. 2  is a perspective view of a front fork assembly. 
         FIG. 3  is a front view of a portion of a bicycle and front fork assembly of  FIG. 2 . 
         FIG. 4  is a cross-section view of a portion of the front fork assembly of  FIG. 2  taken along line  4 - 4  of  FIG. 3 . 
         FIG. 5  is a perspective view of a portion of a partially disassembled front fork assembly. 
         FIG. 6  is a perspective view of a portion of a rear frame portion. 
         FIG. 7  is a perspective partially disassembled view of the portion of the rear frame portion of  FIG. 6 . 
         FIG. 8  is a cross-section view of the portion of a rear frame portion of  FIG. 6  taken along line  8 - 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  illustrates a bicycle, which is referred to generally by the reference numeral  10 . The bicycle  10  includes a frame  12 , which rotatably supports a wheel support, or front fork assembly  14 , near a forward end of the frame  12  for rotation about a steering axis. A lower end of the fork assembly  14  supports a front wheel  16  of the bicycle  10 . A handlebar assembly  18  is connected to an upper end of the fork  14  for rotating the fork assembly  14  and front wheel  16  about the steering axis of the bicycle  10 . In addition, the handlebar assembly  18  may include one or more rider controls, such as shifting or braking controls. 
     A rear wheel  20  of the bicycle  10  is supported near a rearward end of the frame  12 . A pedal crank assembly  22  is rotatably supported by a lower portion of the frame  12 . A drive chain  24  extends between the pedal crank assembly and the rear wheel to transfer power therebetween, as is well known in the art. 
     A front brake caliper  26  can be supported by the front fork assembly  14  and is configured to selectively apply a squeezing force to a rim of the front wheel  16 . Similarly, a rear brake caliper  28  can be supported by the frame  12  and configured to selectively apply a squeezing force to a rim portion of the rear wheel  20 . Alternatively, other types of braking systems may also be used. 
     A seat post  30  extends in an upward direction from the frame  12  and supports a seat  32  on its upper end. The seat post  30  may be adjusted in height relative to the frame  12  to adjust a seat height of the bicycle  10 . 
     Preferably, the frame  12  includes a main frame portion  34  and a wheel support, or rear frame portion  36 . The rear frame portion  36  desirably includes a pair of lower legs, or chain stay members  38  (only one shown), extending on each side of the rear wheel  20  from a lower portion of the main frame  34 . In addition, the rear frame portion  36  includes a pair of upper legs, or seat stay members  40 , extending from an upper portion of the main frame  34  on each side of the rear wheel  20  and being connected to a rear end of the chain stays  38  near a hub axis of the rear wheel  20 . 
     At least the main frame  34  can be constructed from a plurality of tubular, metal pieces welded together. For example, the main frame  34  may be constructed from aluminum, steel or titanium tubing. Alternatively, the frame may comprise a composite material and may be constructed as a unitary piece or multiple pieces bonded or molded together. In addition, other suitable materials and/or construction methods may also be used, as will be appreciated by one of skill in the art. 
     As described above, the front fork assembly  14  preferably is constructed to reduce the amount of vibration passed from the front wheel  16  to the handlebar assembly  18 , and thus the rider of the bicycle  10 . Additionally, other components of the bicycle  10  may also be constructed to reduce vibration transfer. For example, the seat post  30  may be constructed to include a damping system  60   a  ( FIG. 1 ), to reduce the transmission of vibrations from the frame  12  to the seat  32  and, thus, the rider of the bicycle  10 . Furthermore, other components and/or portions of the bicycle  10 , such as the chain stays  38  or seat stays  40  of the frame  12 , may be similarly arranged to include a damping system  60   b ,  60   c,  respectively, to reduce the transmission of vibrations from the wheels  16 ,  20  to the rider of the bicycle  10 , as will be appreciated by one of skill in the art in light of the teachings of the present application. 
     With reference to  FIGS. 2 and 3 , one embodiment of a front fork  14  is illustrated in greater detail. In  FIG. 2 , the front wheel  16  has been omitted and in  FIG. 3 , the front wheel  16  is shown in phantom for the purpose of clarity. As is described in greater detail below, preferably, the fork  14  can be constructed as a composite of a plurality of sheets of a carbon fiber material within an epoxy resin matrix and incorporates a vibration damping system  60  that can include an elastomeric material. Preferably the elastomeric material comprises a thermoplastic elastomer, and more preferably a viscoelastomeric material, as is described in greater detail below. 
     A steer tube  42  of the front fork assembly  14  extends through the frame  12  of the bicycle  10  and supports the handlebar assembly  18  ( FIG. 1 ) at its upper end. A pair of fork legs  44 ,  46  extend downward from the steer tube  42  on opposing sides of the front wheel  16 . The fork legs  44 ,  46  are interconnected at an upper end  48 , which is also connected to the steer tube  42 . An intermediate portion  56  of the fork legs  44 ,  46  connects the upper portion  48  to the lower portion  52 . Thus, each fork leg  44 ,  46  is a generally rigid member that defines a substantially constant length. That is, preferably, the fork assembly  14  is constructed such that relative movement between the front wheel  16  and the bicycle frame  12  along the axis of the fork leg is substantially prevented. Such a construction is commonly referred to as an unsuspended, or rigid, fork assembly. Furthermore, desirably, the fork legs  44 ,  46  and the steer tube  42  are of a one-piece construction. 
     A drop out  50  is secured to or integrally formed with a lower end  52  of each fork leg  44 ,  46 . The drop outs  50  are sized and shaped to receive an axle portion of a hub  54  of the front wheel  16 . In one arrangement, the drop outs  50  are constructed of a metal, such as aluminum or steel, and are secured to the fork legs  44 ,  46  by a bonding process. In another arrangement, the dropouts  50  are integrally formed with the fork legs  44 ,  46  of a carbon fiber material. However, other suitable arrangements to connect the front wheel  16  to the fork assembly  14  may also be used. 
     With reference to  FIGS. 1 and 2 , desirably, the fork legs  44 ,  46  are arranged such that the hub  54  is supported on a forward side of an axis A defined by the steer tube  42 . This is commonly referred to as the “rake” or offset of the fork  14 . Such an arrangement adjusts the stability of the handling characteristics of the bicycle  10 , as is well known in the art. 
     As mentioned previously, a damping system  60  can be used to reduce and isolate terrain-induced vibrations from reaching the rider of the bicycle. A damping system  60  can be used on at least one of each fork leg  44 ,  46 , the seat post  30 , each seat stay  40  and each chain stay  38 . As will be shown, the damping system  60  can be configured to force a damping member into contact with a component of the bicycle, for example, a fork leg. In addition, as also will be shown, the damping system  60  can be configured to sandwich a damping member between a component of the bicycle, for example, a fork leg, and a second member such as a fastener or plate. The damping member can contact a surface cavity in the component. In some embodiments, the second member can force the damping member into contact with the component. In some embodiments, a damping member can be forced into contact with the component, such as with a fastener that secures the damping member to the component. In some embodiments, a damping member can be sandwiched between a plate and a component and can be forced into contact with the component with a fastener that secures to the plate and/or to the component or that further sandwiches the component between the plate and fastener. In some embodiments, the fastener can be part of the plate, such as a protrusion and/or snap fit that extends from the plate. The fastener can be threaded, snap fit, or other type of fastener and can also include one or more fasteners. In some embodiments, the fastener or part of the fastener can be made integrally with the damping member. In some embodiments, a fastener can be attached directly to the damping member. The plate can be a rigid plate. The plate can contact substantially all, a majority of, or some of a surface of the damping member that is not contacting the component. Other embodiments and configurations can also be used, a few examples of which follow below. 
     A surface cavity can be a depressed portion in the component, such as a depression in a fork leg. The depressed portion can be depressed relative to a surrounding surface. The depressed portion does not pass all the way through the component and can have a back wall and side walls. In other embodiments, the depressed portion can be rounded or pointed so that the transition between the side walls and back wall may not be clearly defined. In addition, the side walls may also form the back wall, such as when the side walls form a “V” within the depression. The depressed portion can be any number of shapes and can be configured to maximize contact with the damping member. The depressed portion can be formed in many ways, such as being integrally formed with the component or material may be removed to form the depressed portion. In addition, the depressed portion can extend along the surface between two or more sides of the component. 
     Looking to  FIGS. 4-5 , one embodiment of a damping system  60  has a damping member  84  on an outside surface  62  of a fork leg  44 ,  46 . As shown, the damping member  84  is placed into a surface cavity  66  in the fork leg. A plate  80  secures the damping member  84  in place and forces the damping member  84  into contact with the surface of the fork leg. This forced contact with the surface of the fork leg helps to ensure a resulting damping effect. As mentioned previously, the damping member  84  can be an elastomeric material. 
     As shown, the damping member  84 , plate  80 , and surface cavity  66  are all essentially U-shaped and extend around two opposing surfaces of the fork leg. The damping system  60  extends from an inner side of the fork leg near the wheel, to the back of the fork leg, and then around to the outer side. It will be understood that parts of the damping system  60  can extend across various surfaces of the component. For example, parts of the damping system could wrap around two or more sides of the fork leg. 
     The damping member can be shaped and contoured to extend along the surface of a component between a first side and a second side, where the sides are opposing sides or adjacent sides. The damping member  84  can be generally U-shaped, C-shaped, J-shaped, etc., so that the damping member extends along the surface of the component from one side to another side. The damping member can be positioned partially or entirely within a surface cavity  66 . For example, the damping member can be essentially co-extensive with the surface cavity or the damping member can extend past the surface cavity such that only a portion of the damping member is positioned within the surface cavity and a portion of the damping member extends along a surface of the component outside of the surface cavity. 
     As shown, the damping member can include two halves that are substantially mirror images of one another. In other embodiments, one half can be longer than the other. For example, the damping member can be J-shaped such that the member extends to a greater extent along the outer side then along the inner wheel side of the fork leg. In addition, as shown, the ends of the damping member are narrower than the middle section. Other configurations are also possible. 
     The surface cavity can extend along the outer surface or wall of the fork leg from the outer side to the inner side. The damping member can be contoured to fit within and positioned within said surface cavity, thereby extending along the outer wall between opposing sides of the outer wall. As mentioned, the surface cavity can be smaller than the damping member. In some embodiments, the surface cavity is only slightly smaller than the damping member such that the damping member is forced into tight engagement and contact with the wall of the surface cavity. In some embodiments, the damping member extends along the fork leg outside of the cavity. 
     The plate  80  is also shown as U-shaped, but can also be C-shaped, J-shaped, etc., so that the plate extends along the surface of the damping member from one side of the component to another side. The plate can also be co-extensive with the damping member, or may cover a greater or smaller area than the damping member. 
     Looking at  FIGS. 2-5 , it can be seen that the surface cavity  66  extends along the outer side of the fork leg, around the back of the fork leg and along the inner wheel side of the fork leg. The damping member  84  extends along the outer surface of the fork leg within the surface cavity  66 . Thus, the damping member  84  also extends along the outer side of the fork leg, around the back of the fork leg and along the inner wheel side of the fork leg. The plate  80  extends along an outer surface of the damping member, essentially coextensive with the damping member  84 . 
     A fastener  82  can pass through one side of the plate  80  and engage the other side of the plate  80 . As has been mentioned, the fastener can be part of the plate, such as a protrusion and/or snap, or a separate threaded, snap fit, or other type of fastener. The fastener  82  may also include one or more fasteners. Bolt tension can compress the damping member  84  into contact with the surface of the fork leg allowing the damping member to influence the vibrations being transmitted through the fork leg. 
     In other embodiments, fasteners can be used to connect directly to the damping member. For example, a fastener can connect to a damping member in a similar manner as shown in  FIG. 4  but without the plate. The damping member can be a solid piece that accepts the fastener into the damping member or the fastener may pass through the damping member. 
     The damping member can also be formed with one or more projections. The projections can be configured to hold the damping member in place. In some embodiments, the projections can have a head, flange, or other contact surface on an end. The head can be used to maintain the damping member in place, similar to a head on a fastener. In this way, the projections can be used in place of or in addition to one or more fasteners. The projection with a head or contact surface can also be used to force the damping member into contact with the fork leg or other component and result in a damping effect. 
     The damping system  60  can also be positioned to be at an angle relative to the length of the fork leg. As shown, the damping system is angled to extend downward towards the ground. The damping system  60  can be positioned to be at any desired angle. 
     Preferably, the damping system  60  is located within the intermediate portion  56  of each fork leg  44 ,  46 . The damping member  84  can be elongated and/or contoured or otherwise shaped so as to advantageously maximize the contact area between the damping member  84  and the fork leg  44 ,  46  within the space available, which enhances vibration damping, while preserving the strength and stiffness of the fork  14 , which improves handling. 
     Desirably the damping member  84  is substantially solid and, preferably, is completely solid. Such an arrangement advantageously provides consistent, uniform vibration damping performance of the damping system  60 . In addition, desirably, the cross-sectional area of the damping member  84  is great enough to effectively dampen vibrations from reaching the rider of the bicycle  10 . 
     With reference to  FIG. 4 , the right fork leg  44  is shown in a cross-sectional view taken along a horizontal plane and intersecting the damping system  60 . As used herein, a vertical, longitudinal plane extends along the length of the bicycle  10  and is substantially aligned with a plane defined by the frame  12  and wheels  16 ,  20 . A vertical, lateral plane is substantially normal to the longitudinal plane and a horizontal plane is substantially normal to both the longitudinal and lateral planes. 
     The cross-section of the damping member  84  can have any of a variety of shapes. For example, the damping member  84  can be wedge shaped or trapezoidal. The shape of the cross-section can allow for increased contact with the surface cavity  66  and can increase the effectiveness of the bolt tension and the sandwiching effect to press the damping member  84  into contact with the fork leg and reduce transmitted vibrations. In some embodiments, the damping member  84  can further include a cavity  88  and rim  90 . The plate  80  can be inserted into the cavity  88 . The cavity  88  can be sized so as to be slightly smaller then the plate  80 . This can cause the plate to force the rim  90  to move outwardly and further into contact with the sides of the cavity  66 . 
     As illustrated, desirably, the fork leg  44  is of a thin wall, hollow construction to reduce weight. The fork leg  44  has an outside surface  62 , and an inside surface  64 , where the inside surface is the surface closest to the wheel  16 . As shown, both the inside and outside surfaces can define a cavity  66 , for receiving a damping member  84 . The fastener  82  can be advanced through a plate  80  from the inside surface towards the outside surface to attach to the other side of the plate  80 . This can allow the fastener or the head of the fastener to be on the inside near the wheel  16  and therefore not be readily apparent. The plate  80  can also be used as a badge for branding or stylistic purposes. 
     Although not shown in detail, desirably, the left fork leg  46  can be substantially a mirror image of the left fork leg  44 . However, as will be readily appreciated by one of skill in the art, in other aspects the damping system  60  of the left fork leg  46  can be substantially identical to that described above. 
     When constructed substantially as described in any of the embodiments above, the fork assembly inhibits or reduces vibrations from passing through the fork legs  44 ,  46 . Thus, vibrations originating at the lower end  52  of the fork legs  44 ,  46  (i.e., at the front wheel  16 ) are inhibited, or reduced in magnitude, from passing to the upper ends  48  and steer tube  42  of the fork and, thus, the handlebar  18  of the bicycle  10 . Such an arrangement improves the comfort of the rider and reduces fatigue during long rides. 
     Preferably, the entire fork assembly, with the exception of the damping system, is constructed in a manner conventional for composite bicycle forks. However, the fork assembly may be constructed by any other suitable method. Advantageously, the fork assembly can be lighter weight than prior fork assemblies that used damping systems with an insert, such as where a cavity passed all the way through the fork. This is because of the reduction in the amount of material necessary for creating surface cavities as opposed to cavities that pass completely through the fork leg. Also, for carbon fiber, the improved design allows for better lay-up control by the elimination of the need for two bladders and two carbon tubes to create the cavities. Thus, one bladder can be used and in some embodiments the one bladder can be used to create the space above, below, behind, and to the sides of the surface cavity. Similar benefits are also experienced in use with the damper system  60  in other areas of the bicycle, such as the seat stays, seat tube, and chain stays. 
     Turning now to  FIGS. 6-8 , an embodiment of a damping system  60   c  is shown, in use with the seat stays  40  of a rear frame portion  36 . As shown, the damping member  84  is placed into a surface cavity  66  in the seat stay  40 . A threaded fastener  82  engages a plate  80  which secures the damping member  84  in place and thereby forces the damping member  84  into contact with the surface of the seat stay  40 . Thus, the damping member  84  is sandwiched between the seat stay  40  and the plate  80 . The bolt tension can compress the damping member  84  into contact with the surface of the seat stay  40  allowing the damping member to influence the vibrations being transmitted through the seat stay  40 . This forced contact with the surface of the seat stay  40  helps to ensure a resulting damping effect. 
     As shown, the damping member  84 , plate  80 , and surface cavity  66  are all essentially U-shaped and extend around two opposing surfaces of the seat stay  40 . The damping system  60  extends from an inner side of the seat stay  40  near the wheel, to the back of the seat stay  40 , and then around to the outer side. It will be understood that parts of the damping system  60  can extend across various surfaces of the component. For example, parts of the damping system could wrap around two or more sides of the seat stay  40 . 
     The damping member can be shaped and contoured to extend along the surface of a component between a first side and a second side, where the sides are opposing sides or adjacent sides. The damping member  84  can be generally U-shaped, C-shaped, J-shaped, etc., so that the damping member extends along the surface of the component from one side to another side. The damping member can be positioned partially or entirely within a surface cavity  66 . For example, the damping member can be essentially co-extensive with the surface cavity or the damping member can extend past the surface cavity such that only a portion of the damping member is positioned within the surface cavity and a portion of the damping member extends along a surface of the component outside of the surface cavity. 
     As shown, the damping member can include two halves that are substantially mirror images of one another. In other embodiments, one half can be longer than the other. For example, the damping member can be J-shaped such that the member extends to a greater extent along the outer side then along the inner wheel side of the seat stay  40 . In addition, as shown, the ends of the damping member are narrower than the middle section. Other configurations are also possible. 
     The surface cavity can extend along the outer surface or wall of the seat stay  40  from the outer side to the inner side. The damping member can be contoured to fit within and positioned within said surface cavity, thereby extending along the outer wall between opposing sides of the outer wall. As mentioned, the surface cavity can be smaller than the damping member. In some embodiments, the surface cavity is only slightly smaller than the damping member such that the damping member is forced into tight engagement and contact with the wall of the surface cavity. In some embodiments, the damping member extends along the seat stay  40  outside of the cavity. 
     The plate  80  is also shown as U-shaped, but can also be C-shaped, J-shaped, etc., so that the plate extends along the surface of the damping member from one side of the component to another side. The plate can also be co-extensive with the damping member, or may cover a greater or smaller area than the damping member. 
     Preferably, the damping system  60  is located within the intermediate portion of each seat stay  40 . The damping member  84  can be elongated and/or contoured or otherwise shaped so as to advantageously maximize the contact area between the damping member  84  and the seat stay  40  within the space available, which enhances vibration damping, while preserving the strength and stiffness of the seat stay  40 . For example, as shown in  FIG. 8 , the damping member  84  can have a trapezoidal cross-section. This can allow for increased contact with the surface of the seat stay  40  and can increase the effectiveness of the bolt tension and the sandwiching effect to press the damping member  84  into contact with the seat stay surface and reduce transmitted vibrations. 
     In some embodiments, the damping member  84  can further include a cavity  88  and rim  90 . The plate  80  can be inserted into the cavity  88 . The cavity  88  can be sized so as to be slightly smaller then the plate  80 . This can cause the plate to force the rim  90  to move outwardly and further into contact with the sides of the cavity  66  in the seat stay  40 . 
     Similar to the fork leg, the seat stay  40  can be of a thin wall, hollow construction to reduce weight. The seat stay  40  can also have an outside surface  62 , and an inside surface  64 , where the inside surface is the surface closest to the wheel  20 . As shown, both the inside and outside surfaces define a cavity  66  that extends along the seat stay from the inside surface to the outside surface, for receiving a damping member  84 . The fastener  82  can be advanced through the plate from the inside surface towards the outside surface to attach to the other side of the plate  80 . This can allow the fastener or the head of the fastener to be on the inside near the wheel  20  and therefore not readily apparent. The plate  80  can also be used as a badge for branding or stylistic purposes. 
     In other embodiments, fasteners can be used to connect directly to the damping member. Alternatively, the damping member can be formed with one or more projections, such as projections with a head, flange, or other contact surface. The projection with a head or other contact surface can be used to compress the damping member into contact with the seat stay or other component and result in a damping effect. Thus, the projections can function in the same or a similar way as a fastener. 
     When constructed substantially as described in any of the embodiments above, the rear frame portion with damping system inhibits vibrations from passing through the seat stays  40 . Thus, vibrations originating at the lower end of the seat stays (i.e., at the back wheel  20 ) are inhibited from passing to the upper ends and to the main frame  34 . Such an arrangement improves the comfort of the rider and reduces fatigue during long rides. 
     Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while a number of variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow. 
     Similarly, this method of disclosure, is not to be interpreted as reflecting an intention that any claim require more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment.