Priority Document

[0001] The present application claims priority from Australian Provisional Patent Application No. 2014903546 titled "CYCLE FRAME" and filed on 5 September 2014, the content of which is hereby incorporated by reference in its entirety.

Background of the Invention

[0002] This invention relates to a cycle frame and bicycle incorporating a cycle frame. Description of the Prior Art

[0003] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that the prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

[0004] W094/26579 describes a bicycle frame formed as a monocoque and having a generally Z-shaped side elevation, as well as a front fork assembly for a bicycle comprising two stays having wheel mounting means for supporting a wheel between the members, the stays being joined at one end, the stays both being shaped as aerofoils in cross section each having a rounded leading edge and each having side surfaces which taper rearwardly from the leading edge to intersect to define a knife-edge-like rearward edge. The document also describes a bicycle frame having a plurality of stays for mounting a wheel to the remainder of the frame wherein the stays are in the form of cantilever arms extending away from the remainder of the frame and wherein the stays flex to allow motion of a wheel relative to the remainder of the frame. The document also describes a bicycle seat which is adapted to incorporate a detachable container for drinking fluid and a detachable container having connecting means for connecting the container to a bicycle seat to form a rearward exterior of the bicycle seat, the container being shaped to continue the contours of the seat. Summary of the Present Invention

[0005] In one broad form the invention seeks to provide a cycle frame including:

a) a top portion extending from a head end to a seat mounting, the top portion including a reservoir recess;

b) a connecting portion extending from the seat mounting to a bottom bracket mounting;

c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end; and,

d) a fluid reservoir removably mounted within the reservoir recess in use, wherein the fluid reservoir is shaped so that the fluid reservoir and top portion cooperate to define an aerodynamic profile.

[0006] Typically the reservoir recess is provided in an upper surface of the top portion.

[0007] Typically the reservoir recess extends substantially along a length of the top portion.

[0008] Typically the fluid reservoir is at least partially transparent to thereby allow fluid levels within the fluid reservoir to be observed.

[0009] Typically the fluid reservoir includes one or more reservoir portions that contain respective fluids in use.

[0010] Typically the fluid reservoir includes a lower surface extending downwardly to a sump so that fluid drains into the sump.

[0011] Typically the reservoir includes a drinking tube extending from the fluid reservoir, the drinking tube terminating within the sump thereby allowing fluid to be removed from within the sump.

[0012] Typically the reservoir recess includes a seat mounting face including apertures extending through a seat mounting that receive seat mounting bolts, the seat mounting bolts threadingly engaging a removable seat clamp to thereby clamp a seat post within the seat mounting.

[0013] Typically, the fluid reservoir includes a refill port. [0014] Typically, the refill port is covered by a plurality of flexibly resilient leaves which, in use, deflect out of the way to allow fluid to enter the refill port.

[0015] Typically, the refill port is disposed through an upper surface of the fluid reservoir. [0016] Typically the reservoir recess is provided in a lower surface of the top portion. [0017] Typically the reservoir recess extends part way down the connecting portion. [0018] Typically the reservoir recess is provided in a lateral side surface of the top portion.

[0019] In another broad form the invention seeks to provide a cycle frame including:

a) a top portion extending from a head end to a seat mounting, the top portion including a substantially elongate through-opening extending from a first side of the top portion to a second side of the top portion;

b) a connecting portion extending from the seat mounting to a bottom bracket mounting;

c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end; and,

d) a fluid reservoir removably mounted within the through-opening in use, wherein the fluid reservoir is shaped so that the fluid reservoir and top portion cooperate to define an aerodynamic profile.

[0020] In another broad form the invention seeks to provide a cycle frame including:

a) a top portion extending from a head end to a seat mounting;

b) a connecting portion extending from the seat mounting to a bottom bracket mounting; and,

c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end and wherein the wheel mounting portion includes a derailleur recess positioned between the bottom bracket mounting and the wheel mounting end that in use receives at least part of a front derailleur assembly.

[0021] Typically the derailleur recess receives at least one of:

a) a derailleur housing;

b) part of derailleur linkages; c) a derailleur actuator;

d) a derailleur servo; and,

e) a derailleur battery.

[0022] Typically the recess includes a first recess portion that receives at least one of the derailleur servo, part of derailleur linkages and a derailleur housing, and a second recess portion that receives the derailleur battery.

[0023] Typically the wheel mounting portion includes at least one stay extending from the bottom bracket mounting to the wheel mounting end, the stay having an inner surface facing a rear wheel of the cycle in use and an opposing outer surface, the derailleur recess being provided in the outer surface.

[0024] Typically when at least part of a front derailleur assembly is received in the recess, at least part of the front derailleur assembly is substantially flush with the outer surface of the stay.

[0025] Typically the stay between the recess and the inner surface defines a mounting plate for at least part of the derailleur.

[0026] Typically the stay between the recess and the inner surface is made of aluminium sandwiched between carbon fibre outer layers.

[0027] Typically the wheel mounting portion includes first and second stays positioned on either side of a rear wheel of the cycle in use, and wherein the derailleur recess is provided in the first stay and a support section is provided in the second stay to provide additional support against lateral loading on the rear wheel.

[0028] Typically the support section includes a ridge extending along at a length of the second stay corresponding to a length of the recess along the first stay.

[0029] In another broad form the invention seeks to provide a cycle frame including:

a) a top portion extending from a head end to a seat mounting;

b) a connecting portion extending from the seat mounting to a bottom bracket mounting; and, c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end and wherein the wheel mounting portion includes a stay having a profile that diverts airflow around at least one of:

i) part of a gear cassette mounted on a rear wheel of the cycle in use; and, ii) part of a rear derailleur.

[0030] Typically the stay includes an inner surface substantially parallel to the rear wheel in use to thereby reduce airflow between the rear wheel and the stay.

[0031] Typically the stay includes an outer surface extending away from the rear wheel towards the wheel mounting end to divert airflow outwardly of the gear cassette.

[0032] Typically the stay includes upper and lower surfaces positioned to direct air above and below the gear cassette respectively.

[0033] Typically the stay includes an outwardly sloped portion on at least an inner part of a rear surface, the outwardly sloped portion being adapted to conform to and at least partially accommodate at least part of the gear cassette.

[0034] Typically the stay includes a downwardly sloped portion on at least a lower part of a rear surface, the downwardly sloped portion being adapted to at least partially accommodate at least part of a rear derailleur.

[0035] Typically the seat mounting includes a substantially rectangular opening for receiving a rectangular seat tube.

[0036] Typically the head end includes a head tube opening that accommodates a stem coupled to handlebars and at least one fork that supports a front wheel in use.

[0037] Typically the frame includes a wheel mounting coupled to the wheel mounting end, the wheel mounting supporting an axle of a rear wheel.

[0038] Typically the frame is substantially Z-shaped.

[0039] Typically the frame is a carbon fibre shell containing expanded foam. [0040] Typically the frame is a monocoque frame in which the top portion, connecting portion and wheel mounting portion are integrally formed.

[0041] Typically at least the top and connecting portions include a curved leading edge and tapered trailing edge.

[0042] Typically the connecting portion includes a central waist and wherein the connecting portion widens and lengthens from the central waist towards the seat mounting and the bottom bracket mounting.

[0043] Typically an underside of the top portion curves downwardly to form into a leading edge of the connecting portion.

[0044] Typically a trailing edge of the connecting portion is shaped to conform to a shape of an outer surface of a rear wheel.

[0045] In another broad form the invention seeks to provide a cycle frame including:

a) a top portion extending from a head end to a seat mounting;

b) a connecting portion extending from the top portion to a bottom bracket mounting; and,

c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end and wherein the wheel mounting portion includes a derailleur recess positioned between the bottom bracket mounting and the wheel mounting end that in use receives at least part of a front derailleur assembly.

[0046] Typically, the connecting portion extends from the head end to the bottom bracket mounting.

[0047] Typically, the frame is substantially V-shaped.

[0048] Typically, the frame further includes a seat tube which extends from the seat mounting to the bottom bracket mounting such that the top portion, seat tube and connecting portion form a triangular shape.

[0049] In another broad form, the invention seeks to provide a cycle frame including: a) a top portion extending from a head end to a seat mounting;

b) a connecting portion extending from the top portion to a bottom bracket mounting; and,

c) a wheel mounting portion extending from the bottom bracket mounting to a wheel mounting end and wherein the wheel mounting portion includes a stay having a profile that diverts airflow around at least one of:

i) part of a gear cassette mounted on a rear wheel of the cycle in use; and, ii) part of a rear derailleur.

Brief Description of the Drawings

[0050] An example of the present invention will now be described with reference to the accompanying drawings, in which: -

[0051] Figure 1 A is a schematic isometric view of an example of a cycle frame;

[0052] Figure IB is a schematic side view of the cycle frame of Figure 1A;

[0053] Figure 1C is a schematic rear view of the cycle frame of Figure 1 A;

[0054] Figure ID is schematic front view of the cycle frame of Figure 1 A;

[0055] Figure IE is a schematic side view of a bicycle incorporating the cycle frame of

Figure 1A;

[0056] Figure 2A is a schematic isometric view of the cycle frame of Figure 1A in an exploded configuration;

[0057] Figure 2B is a schematic rear isometric view of the cycle frame of Figure 1 A with the fluid reservoir and seat clamp omitted;

[0058] Figure 2C is a schematic side view of the cycle frame of Figure 1A in the exploded configuration;

[0059] Figure 2D is a schematic plan view of the cycle frame of Figure 1A showing an example of a gear cassette in use;

[0060] Figure 2E is a schematic underside view of the cycle frame of Figure 1A showing an example of a gear cassette in use;

[0061] Figure 3A is a schematic side view of the cycle frame of Figure 1A showing cut through views;

[0062] Figure 3B is schematic cut through view along the line of A-A;

[0063] Figure 3C is schematic cut through view along the line of B-B'; [0064] Figure 3D is a schematic cut through view along the line C-C;

[0065] Figure 3E is a schematic cut through view along the line D-D';

[0066] Figure 3F is a schematic cut through view along the line E-E';

[0067] Figure 3G is a schematic cut through view along the line F-F';

[0068] Figure 3H is a schematic cut through view along the line G-G';

[0069] Figure 4 is a schematic side view of a further example of a cycle frame having provision for a recessed front derailleur;

[0070] Figure 5 is a schematic side view of another example of a cycle frame having provision for a recessed front derailleur;

[0071] Figure 6 is a schematic perspective view of an example of a fluid reservoir having a refill port;

[0072] Figure 7 is a schematic perspective view of a further example of a fluid reservoir having a refill port;

[0073] Figure 8 is a schematic perspective view of another example of a fluid reservoir having a refill port;

[0074] Figure 9A is a schematic side view of a further example of a cycle frame having a through-opening in the top portion of the frame;

[0075] Figure 9B is a schematic side view of the cycle frame of Figure 9A showing an example of a fluid reservoir located within the through-opening of the top portion of the frame;

[0076] Figure 1 OA is a schematic side view of a further example of a cycle frame having a recess underneath the top portion of the frame;

[0077] Figure 10B is a schematic side view of the cycle frame of Figure 10A showing an example of a fluid reservoir located in the recess underneath the top portion of the frame;

[0078] Figure 11A is a schematic side view of a further example of a cycle frame having a recessed top portion including a longitudinally extending web;

[0079] Figure 1 IB is a first example of a sectional view along H-H' through the top portion of the cycle frame of Figure 11 A;

[0080] Figure 11C is the same sectional view as shown in Figure 11B with fluid reservoirs mounted in recessed portions of the top portion of the cycle frame;

[0081] Figure 11D is a second example of a sectional view along H-H' through the top portion of the cycle frame of Figure 11 A; [0082] Figure HE is the same sectional view as shown in Figure 11D with fluid reservoirs mounted in recessed portions of the top portion of the cycle frame;

[0083] Figure 1 IF is a third example of a sectional view along H-H' through the top portion of the cycle frame of Figure 11 A; and,

[0084] Figure 11G is the same sectional view as shown in Figure 11D with a fluid reservoir mounted in a recessed portion of the top portion of the cycle frame.

Detailed Description of the Preferred Embodiments

[0085] An example of a cycle frame will now be described in more detail with more reference to Figures 1 A to IE.

[0086] In this example, the frame 100 includes a top portion 110 extending from a head end 111 to seat mounting 112, a connecting portion 120 extending from the seat mounting 112 to a bottom bracket mounting 131 and a wheel mounting portion 130 extending from the bottom bracket mounting 131 to a wheel mounting end 132.

[0087] A number of different components can be attached to the frame 100 to form a functioning bicycle and examples of these will now be described.

[0088] The head end 111 typically includes a head tube opening, in which is provided a stem 141, with a headset coupled to handle bars 142 and one or more forks 143 that support a front wheel 144 in use, although any suitable arrangement can be used. The seat mounting 112 is typically used to support a seat post 145 coupled to a seat 146, and an example of this arrangement will be described in more detail below.

[0089] In this example, the wheel mounting portion 130 includes two stays 134, 135 that extend along either side of the rear wheel 152, although single mono-stay arrangements could also be used. A wheel mounting 150 is coupled to the wheel mounting end 132 at the end of each stay 134, 135, which supports an axle 151 of a rear wheel 152 and which also has a cassette gear 153 mounted thereon. A rear derailleur 154 may also be coupled to the wheel mounting 150.

[0090] The bottom bracket mounting 131 typically includes an opening 133 extending laterally through the frame 100 that receives a crank set 160 including chain rings 161, a crank 162 and pedals 163, that in use drive a chain 164. A front derailleur 165 can also be provided allowing the chain to be selectively moved between different chain rings 161. In the example of Figure IE, the front derailleur 165 is coupled to the connecting portion 120 of the frame 100, in accordance with standard mounting configurations, although alternative arrangements can be used, as will be described in more detail below.

[0091] In this example, the top portion 110 and wheel mounting portion 130 extend in substantially parallel directions and are aligned generally horizontal, when the bicycle is supported on a horizontal surface. The connecting portion 120 extends generally vertically between the top and wheel mounting portions 110, 130 to define a substantially "Z" shaped frame 100.

[0092] The frame 100 is typically a carbon fibre shell containing a foam, such as extruded polystyrene, or polyurethane foam, which is typically of sufficient strength to add structural strength to the carbon fibre shell. Whilst in some embodiments foam may be injected into the shell, this is not essential and the addition of foam will be dependent upon the manufacturing technique used. The frame 100 is generally formed as a monocoque frame, with the top portion 110, connecting portion 120 and wheel mounting portion 130 being integrally formed. Further details of the specific frame construction will be described in more detail below.

[0093] A number of further features will now be described with reference to Figures 2A to 2E.

[0094] One broad feature is that the top portion 110 includes a reservoir recess 211, and wherein a fluid reservoir 270 is removably mounted within the reservoir recess 211 in use. The fluid reservoir 270 is shaped so that the fluid reservoir 270 and top portion 110 cooperate to define an aerodynamic profile. It is to be understood that the term 'within' used in the above context should be taken to mean that the fluid reservoir is mounted within an extent of an aerodynamic profile of the frame and not internally inside of any tubular portion of the frame.

[0095] In particular, the fluid reservoir 270 is shaped to conform with parts of the top portion 110 beyond the extent of the reservoir recess 211. For example, the fluid reservoir 270 can include an upper surface 271, which aligns with an upper surface 212 of the top portion 110, forwardly of the fluid reservoir 270, and which also aligns with an upper surface 213 of the seat mounting 112, rearwardly of the fluid reservoir 270. Similarly, side walls 272 of the fluid reservoir align with side walls 214 of the top portion 110. This arrangement avoids discontinuities and obstacles, which can impede air flow, in turn ensuring air flows smoothly round the top portion 110 and reservoir 270, which can assist in significantly reducing aerodynamic drag.

[0096] Accordingly, in this example the shape of the reservoir 270 is adapted to be integrated into the overall shape of the frame 100 to thereby contribute to the aerodynamic effectiveness of the frame 100. This is in contrast to traditional arrangements in which fluid reservoirs, such as water bottles, are generally affixed externally to the frame and do not form part of the aerodynamic profile of the frame 100.

[0097] A number of further features of the reservoir arrangement will now be described.

[0098] In one example, the reservoir 270 is provided in an upper surface of the top portion 110, so that the upper surface 271 of the reservoir 270 forms at least part of an upper surface of the top portion 110. This facilitates fitting and removal of the fluid reservoir 270, allowing this to be easily removed for refilling. Additionally, by ensuring the fluid reservoir 270 is at least partially transparent, for example by manufacturing this from a suitable material or forming a transparent window, this allows a rider to easily observe fluid levels in the fluid reservoir 270, for example by glancing down from their riding position. Allowing the cyclist to visually observe fluid levels is advantageous, particularly in competition scenarios, in terms of allowing the rider to pace their water consumption over the duration of the event. It is however not essential that any part of the reservoir is transparent and in other examples it may not be. The bottle can be made of any suitable material and this could include any one or more of high-density polyethylene (HDPE), low-density polyethylene (LDPE), copolyester, polypropylene, or the like.

[0099] The fluid reservoir 270 typically extends substantially along a length of the upper surface of the top portion 110, thereby maximising the volume of fluid that can be contained, therein, although this is not essential. The fluid reservoir 270 can also include two or more reservoir portions, for example formed by a dividing wall (not shown) running along an internal length of the fluid reservoir 270, that contain respective fluids in use. This can be used to allow different fluids, such as water and an energy drink, to be provided and drunk by the rider as desired, for example via respective drinking tubes.

[0100] The fluid reservoir 270 typically includes a lower surface 273 that generally conforms with a surface of the recess 211. In one example, the lower surface 273 extends downwardly to a sump 274 so that fluid drains into the sump 274. The fluid reservoir 270 can then include a drinking tube (not shown) extending from the fluid reservoir, the drinking tube terminating within the sump 274 thereby allowing fluid to be removed from within the sump 274. In this arrangement, the sump 274 forms the lowest part of the fluid reservoir 270 so that fluid drains preferentially into the sump 274, ensuring that substantially all of the fluid can be extracted from the reservoir using the drinking tube.

[0101] The lower surface 273 of the fluid reservoir 270 can also be shaped, for example, having a concave "V" profile running along the length of the fluid reservoir 270, which cooperates with a corresponding convex "V" profile on the reservoir recess 211, thereby assisting position and centre the fluid reservoir 270 laterally with respect to the top portion 110. Additionally and/or alternatively the fluid reservoir 270 could be retained in position using other techniques, such as friction fit, interference fit or the like. A further alternative is the use of cooperating magnets in the fluid reservoir 270 and the frame 100 to retain the fluid reservoir 270 in position.

[0102] The reservoir recess 211 typically includes a seat mounting face 215 including apertures 216 extending through the seat mounting 112 that receive seat mounting bolts (not shown). The seat mounting bolts threadingly engage a removable seat clamp 280 to thereby clamp the seat post 145 within the seat mounting 112.

[0103] In this example, the seat mounting clamp 280 includes a tapered body 281, having a clamping face 282, which in use is mounted in a correspondingly shaped recess 218 of the seat mounting 112, with the clamping face 282 facing the seat mounting 1 12. The clamping face 282 includes threaded apertures 283 that receive the bolts and a channel 284, which cooperates with a complimentary channel 217 in the seat mounting 112 to define a generally rectangular tube, having chamfered corners, for receiving the seat post 145. In use, the seat mounting bolts can be tightened to draw the seat clamp 280 towards the seat mounting 112 thereby clamping the seat post 145 at a desired position within the tube.

[0104] This arrangement provides a number of advantages. For example, in this configuration, the seat mounting clamp 280 includes internal threads needed to engage the bolts, whereas in traditional seat clamping arrangements these are mounted within the frame. In this example, in the event that the threads become stripped, the seat mounting clamp 280 can be replaced, without necessitating replacement of the entire frame or a structure internal to the frame, which is typically expensive and/or complex to perform. Additionally, the use of the rectangular seat post 145 and tapered seat mounting clamp 280 helps improve the aerodynamic efficiency compared to traditional circular seat post and mounting arrangements.

[0105] In an alternative arrangement, the seat mounting may include an opening to receive the seat tube and a wedge clamp used to restrain the seat tube in the seat mounting. The wedge clamp includes at least one surface shaped to conform with an outer surface portion of the seat tube when tightened. The wedge clamp typically includes a pair of tapered clamp elements held together by a threaded fastener that extends into a blind threaded insert. Tightening the fastener causes the tapered surfaces of the wedge elements to slide relative to each other which thereby exerts a lateral clamping force onto the seat tube which clamps the seat tube securely within the seat mounting.

[0106] The fluid reservoir may additionally include features which allow the reservoir to be refilled on the fly such as during a cycle or triathlon race. In such an event, an athlete may pass a hydration station where it is possible to grab a bottle of fluid to replace or top up a used bottle. To refill a conventional water bottle, typically a lid needs to be unscrewed or flipped open to provide internal access to the bottle. This can be a difficult operation whilst riding a bike and in some cases, an athlete may choose to stop at the hydration station in order to refill bottles.

[0107] In an example, the fluid reservoir may include a refill port enabling a rider to easily refill the reservoir whilst riding, i.e. "on the fly". Examples of filling port arrangements are provided in Figures 6 to 8. In Figure 6, there is shown a fluid reservoir 670 including a refill port 675. The refill port 675 is disposed through an upper surface 671 of the reservoir 670 which provides a convenient position for a rider to access whilst maintaining a substantially aerodynamic posture.

[0108] Typically, the refill port 675 is covered by a plurality of flexibly resilient leaves 676 which, in use, deflect out of the way to allow fluid to enter the refill port 675. For example, an end of a bottle may be inserted into the refill port 675 by deflecting the leaves 676 generally downward which exposes an opening to the reservoir 672. In this respect, the leaves 676 typically hinge about a periphery of the port 675. After refilling, the leaves 676 return to a position which closes the port 675 thereby substantially preventing splash back or spillage. In one example, the leaves 675 may be rubber flaps.

[0109] In the example shown in Figure 7, there is provided a fluid reservoir 770 including a refill port 775 disposed through an upper surface 771 of the reservoir 770 and covered by a plurality of flexibly resilient leaves 776 as previously described. In this example, the refill port 775 additionally includes a flip-top cap 778 adapted to cover the refill port 775 and flexible leaves 776. The cap 778 further reduces the likelihood of spillage or splash back which is particularly useful when filling the reservoir 770 with a sticky sports drink for example.

[0110] A further example of a fluid reservoir 870 having a refill port 875 is provided in Figure 8. In this example, the refill port 875 includes a threaded inlet portion 877 which is threadingly engaged by a cap 878. In this example, the cap 878 includes a plurality of flexibly resilient leaves 876, which in use, cover the refill port 875 and operate in the same manner as previously described.

[0111] In alternative arrangements, the flexibly resilient leaves may be substituted with a permeable membrane or gauze like material which allows fluid to enter the reservoir while minimising splash back and spillage.

[0112] Whilst the previously described examples have included a fluid reservoir provided in an upper surface of the top portion of the frame, other arrangements are possible in which the fluid reservoir forms part of the aerodynamic profile of the frame. [0113] In another example, as shown in Figures 9A and 9B, a cycle frame 900 includes a through-opening 904 that is formed substantially through a top portion 910 of the frame. The through-opening 904 is substantially elongate and extends from a first side of the top portion to a second side of the top portion so as to form an aperture, window or slot.

[0114] In this arrangement, the through-opening 904 divides the top portion 910 into an upper section 913 and a lower section 914, respectively above and below the through- opening 904. A fluid reservoir 970 that is shaped to conform with the profile of the through- opening 904 is mounted within the through-opening 904 as shown in Figure 9B so as to be within the aerodynamic profile of the frame. The reservoir 970 may be fitted into the through-opening 904 from either side of the frame 900.

[0115] A potential advantage of the design shown in Figures 9A and 9B is that the top portion 910 can be made lighter and stronger. The upper and lower sections 913, 914 of the top portion 910 provide a higher section modulus compared to an enclosed tubular structure without the through-opening.

[0116] In a further example, a fluid reservoir 1070 is positioned underneath the top portion

1010 of a cycle frame 1000 as shown in Figures 10A and 10B. In this example, a lower surface of the top portion 1010 may include a reservoir recess 1011 and a fluid reservoir 1070 may be shaped to conform with the recess 1011 and be mounted therein. The profile of the reservoir recess 1011 and fluid reservoir 1070 may take several forms. In the example shown, the recess 1011 follows the contour of the frame 1000 along the top portion 1010 and partway down the connecting portion or seat tube 1020. In other arrangements, the recess

1011 may be substantially in the top portion 1010 only or alternatively may extend further down the connecting portion 1020.

[0117] In one example, the fluid reservoir 1070 may extend down the connecting portion 1020 so as to form the leading edge of the connecting portion or seat tube 1020 which splits air ahead of the rear wheel. In such an example, the fluid reservoir 1070 would form a critical aerodynamic portion of the connecting portion or seat tube 1020.

[0118] Referring now to Figure 11 A, there is shown another example of a cycle frame 1100 including a top portion 1110 including a reservoir recess in a lateral side surface thereof and further including a longitudinally extending web. The web may extend substantially centrally as shown in Figure 11B, be offset as shown in Figure 11D or form a side wall of the top portion as shown in Figure 1 IF.

[0119] In the example shown in Figure 11B, the web 1112 is centrally extending so as to form two substantially symmetrical recesses 1114, 1115. Recesses 1114, 1115 may be used to mount fluid reservoirs 1170, 1171 as shown in Figure 11C. Whilst typically reservoirs 1170, 1171 may both hold water, in other examples each reservoir may hold a different fluid. For example, one reservoir may hold water whilst the other one holds a sports drink. Similar to the design shown in Figure 9 A, the top portion 1110 comprising an upper segment 1111, lower segment 1113 and web 1112 (similar to an I-beam section) provides a structure with increased stiffness and strength and lower weight compared to an enclosed tubular structure.

[0120] In the example shown in Figures 11D and HE, the web 1112 is offset relative to the centre of the top portion 1110 so that asymmetrical recesses 1114.1, 1115.1 are formed for locating fluid reservoirs 1170.1, 1171.1 of different shapes and volume.

[0121] In a further example as shown in Figures 1 IF and 11G, the web 1112 forms part of a lateral side of the top portion 1110 which creates a single recess 1114.2 for locating a fluid reservoir 1170 that has a larger volume than the reservoirs provided in Figures 11C and 1 IE.

[0122] Another broad feature is that the wheel mounting portion 130 includes a derailleur recess 230 positioned between the bottom bracket mounting 131 and the wheel mounting end 132 that in use receives at least part of a front derailleur assembly. In particular, this allows at least part of the front derailleur assembly, such as a battery and/or servo, to be recessed within the frame 100 so that at least part of the front derailleur assembly is within the profile of the wheel mounting portion 130.

[0123] Recessing at least part of the front derailleur assembly avoids or at least reduces the extent to which the front derailleur assembly projects outwardly from the frame 100 when compared to traditional mounting arrangements, as shown for example by the derailleur 165 in Figure IE, which in turn contributes to the overall drag of the bicycle. Furthermore, by moving part of the front derailleur assembly to a region behind the chain rings and crank, this ensures that even if part of the front derailleur assembly projects outwardly from the profile of the wheel mounting portion 130, airflow is already diverted around any projecting portions of the front derailleur assembly by the chain rings and crank, thereby minimising the drag created.

[0124] A number of further features of the derailleur recess will now be described.

[0125] In the current example, the derailleur recess includes two portions 231, 232, which can be used to house a derailleur servo 265 and derailleur battery 267 respectively. Alternatively, this may house part of a derailleur actuator, derailleur linkages and/or a derailleur housing in the case of cable operated derailleurs. It will be appreciated however that this is not essential and a single recess portion may be used. In this regard, the derailleur used in this example is a modified derailleur in which the servo 265 sits at the bottom of the chain guide 266, allowing the servo 265 to be positioned within the recess. However, it will be appreciated that this is not essential and that some benefit can be derived even with the servo and chain guide 165 mounted as per traditional arrangements shown in Figure IE, with the battery contained within the recess 230.

[0126] As previously mentioned, the wheel mounting portion 130 typically includes at least one stay 135 extending from the bottom bracket mounting 131 to the wheel mounting end 132. In this configuration, the stay 135 has an inner surface 234 facing a rear wheel of the cycle in use and an opposing outer surface 233 facing away from the rear wheel, with the derailleur recess being provided in the outer surface 233. In this case, at least part of the front derailleur assembly is substantially flush with the outer surface 233 of the stay to thereby assist in maintaining uninterrupted airflow, and hence reduce drag.

[0127] In the current example, a portion of the stay between the recess 230 and the inner surface 234 can be used to define a mounting plate for at least part of the derailleur. As this portion of the stay is typically relatively thin, with as little as 5 mm thickness, the stay in this portion could be made of aluminium sandwiched between carbon fibre outer layers. This provides additional structural rigidity, as well as allowing the derailleur assembly to be bolted directly to the aluminium inter-layer.

[0128] Whilst a single stay could be used, more typically first and second stays 135, 134 are positioned either side of the rear wheel of the cycle in use. In this case, with the derailleur recess 230 provided in the first stay 135, a support section 237 can be provided in the second stay 134 to provide additional support against lateral loading on the rear wheel. Thus, the support section 237 is designed to provide additional lateral support to counter the reduced lateral support in the first stay 135 resulting from the presence of the recess 230. The support section can be of any appropriate form, but in one example includes a ridge 237 extending along a length of the second stay 134 corresponding to a length of the recess along the first stay. Thus, the ridge 237 is typically of a similar length and aligned at a similar position to the recess 230, albeit on the opposing stay.

[0129] Another broad feature of the above described arrangement is that the first stay 135 can have a profile that diverts airflow around a gear cassette 153 mounted to the rear wheel 152 in use and/or a rear derailleur 154. In this regard, a gear cassette 153 typically includes a number of spaced sprockets, with the rear derailleur 154 being used to selectively engage a drive chain with one of the sprockets, as will be appreciated by person skilled in the art. By diverting airflow around the gear cassette and more typically the gear cassette 153 and at least part of the rear derailleur 154, this reduces airflow incident on the gear cassette and/or rear derailleur 154, which it will be appreciated can contribute to significant drag in traditional arrangements.

[0130] To achieve this, a variety of different stay features can be used, either individually or in combination. For example, the stay 135 can includes an inner surface 234 substantially parallel to the rear wheel in use. This minimises a spacing between the rear wheel 152 and stay 135, which in turn reduces airflow between the rear wheel 152 and the stay 135, and hence reduces airflow incident on the gear cassette 153. The stay 135 can also include an outer surface 233 extending away from the rear wheel towards the wheel mounting end 132 to thereby divert airflow outwardly of the gear cassette 153 and/or rear derailleur 154, as shown by the arrow 251 in Figures 2D and 2E. Furthermore, the stay 135 can include upper and lower surfaces 238, 239 positioned to direct air above and below the gear cassette 153 and/or rear derailleur 154 respectively, as shown by the arrows 250 in Figure 2C.

[0131] Additionally, the stay 135 can include an outwardly sloped portion 235 on at least an inner part of a rear surface, the outwardly sloped portion being adapted to conform to and at least partially accommodate at least part of the gear cassette 153. This can be used to minimise a spacing between the gear cassette and stay 135, thereby reducing airflow therebetween. Similarly, the stay 135 can include a downwardly sloped portion 236 on at least a lower part of a rear surface, the downwardly sloped portion being adapted to at least partially accommodate at least part of a rear derailleur 154, again to thereby minimise airflow between the rear derailleur and the stay.

[0132] Thus, the first stay 135 includes shaped portions 235, 236 that are shaped to conform to the cassette gear 153 and the rear derailleur 154 respectively. Accordingly, it would be appreciated that the chain stay 135 is effectively shaped to divert airflow around the rear gear components to thereby reduce drag.

[0133] Examples of the shape of the frame 100 are shown in Figures 3 A to 3H.

[0134] In particular as shown the top and connecting portions 110, 120 include a curved leading edge and tapered trailing edge, which assists in reducing drag. The connecting portion 120 includes a central waist evident in Figure 3F, with the connecting portion widening and lengthening away from the central waist towards the seat mounting 112 and the bottom bracket mounting 131. This minimises the cross sectional area and hence drag of the frame, whilst also ensuring sufficient strength and rigidity in load bearing areas.

[0135] Furthermore, an underside of the top portion curves 110 downwardly to form into a leading edge of the connecting portion 120, which assists in transmitting stress through the body, whilst ensuring smooth airflow around the connecting portion. A trailing edge of the connecting portion 120 is also shaped to conform to a shape of a rear wheel, thereby minimising airflow between the rear wheel and connecting portion.

[0136] Testing has shown that the above described bike frame can be used to produce a bike having a significantly reduced drag compared to more traditional arrangements of bike frame, over a range of incident airflow angles, of at least ± 20° compared to the direction of travel, which can in turn correspond to an increase in speed during a race. Alternatively, the reduction in drag may enable a rider to cycle at a given speed with less effort which can reduce fatigue and lead to better run performance off the bike in a triathlon for example. [0137] Whilst the above examples have focussed on the use of a "Z" -shaped frame, this is not essential and many of the features can be implemented on more traditional triangular frames. For example, triangular frames could incorporate the fluid reservoir on the top tube and also include similarly shaped chain stays, as well as a modified front derailleur as described. It will therefore be appreciated that reference to a "Z" -shaped frame, whilst particularly advantageous is not intended to be limiting. Additionally, whilst the fluid reservoir, derailleur recess and shaped stay having been described as part of a single example, it will be appreciated that these features could be used independently or in any combination, and the presence of all three features in a single frame whilst beneficial is not essential.

[0138] A further example of a cycle frame will now be described with reference to Figure 4.

[0139] In this example, there is shown a cycle frame 400 including a top portion 410 extending from a head end 411 to a seat mounting 412. A connecting portion 420 extends from the top portion 410 to a bottom bracket mounting 431. More particularly, the connecting portion 420 extends from the head end 411 to the bottom bracket mounting 431. In this way, the frame 400 is substantially V-shaped.

[0140] The cycle frame 400 further includes a wheel mounting portion 430 that extends from the bottom bracket mounting 431 to a wheel mounting end 432. The wheel mounting portion 430 includes a derailleur recess 440 positioned between the bottom bracket mounting 431 and the wheel mounting end 432 that in use receives at least part of a front derailleur assembly. In particular, this allows, at least part of the front derailleur assembly, such as a battery 467 and/or servo 465, to be recessed within the frame 400 so that at least part of the front derailleur assembly is within the profile of the wheel mounting portion 430.

[0141] Recessing at least part of the front derailleur assembly avoids or at least reduces the extent to which the front derailleur assembly projects outwardly from the frame 400 when compared to traditional mounting arrangements, as shown for example by the derailleur 165 in Figure IE, which in turn contributes to the overall drag of the bicycle. Furthermore, by moving part of the front derailleur assembly to a region behind the chain rings and crank, this ensures that even if part of the front derailleur assembly projects outwardly from the profile of the wheel mounting portion 530, airflow is already diverted around any projecting portions of the front derailleur assembly by the chain rings and crank, thereby minimising the drag created.

[0142] In the current example, the derailleur recess includes two portions 441, 442, which can be used to house a derailleur servo 465 and derailleur battery 467 respectively. Alternatively, this may house part of a derailleur actuator, derailleur linkages and/or a derailleur housing in the case of cable operated derailleurs. It will be appreciated however that this is not essential and a single recess portion may be used. In this regard, the derailleur used in this example is a modified derailleur in which the servo 465 sits at the bottom of the chain guide 466, allowing the servo 465 to be positioned within the recess. However, it will be appreciated that this is not essential and that some benefit can be derived even with the servo and chain guide mounted as per traditional arrangements shown in Figure IE, with the battery contained within the recess 440.

[0143] The wheel mounting portion 430 typically includes at least one stay 435 extending from the bottom bracket mounting 431 to the wheel mounting end 432. In this configuration, the stay 435 has an inner surface facing a rear wheel of the cycle in use and an opposing outer surface 433 facing away from the rear wheel, with the derailleur recess 440 being provided in the outer surface 433. In this case, at least part of the front derailleur assembly is substantially flush with the outer surface 433 of the stay to thereby assist in maintaining uninterrupted airflow, and hence reduce drag.

[0144] A further example of a cycle frame will now be described with reference to Figure 5.

[0145] In this example, there is shown a cycle frame 500 including a top portion 510 extending from a head end 511 to a seat mounting 512. A connecting portion 520 extends from the top portion 510 to a bottom bracket mounting 531. More particularly, the connecting portion 520 extends from the head end 511 to the bottom bracket mounting 531. The frame 500 further includes a seat tube 550 which extends from the seat mounting 512 to the bottom bracket mounting 531 such that the top portion 510, seat tube 550 and connecting portion 520 form a triangular shape, also referred to in the art as a front triangle.

[0146] The cycle frame 500 further includes a wheel mounting portion 530 that extends from the bottom bracket mounting 531 to a wheel mounting end 532. Typically, one or more seat stays 570 extend from the seat tube 550 to the wheel mounting end 532. In this way, the seat stay 570, seat tube 550 and wheel mounting portion 530 also form a triangular shape, also referred to in the art as a rear triangle.

[0147] The wheel mounting portion 530 includes a derailleur recess 540 positioned between the bottom bracket mounting 531 and the wheel mounting end 532 that in use receives at least part of a front derailleur assembly. In particular, this allows, at least part of the front derailleur assembly, such as a battery 567 and/or servo 565, to be recessed within the frame 500 so that at least part of the front derailleur assembly is within the profile of the wheel mounting portion 530.

[0148] Recessing at least part of the front derailleur assembly avoids or at least reduces the extent to which the front derailleur assembly projects outwardly from the frame 500 when compared to traditional mounting arrangements, as shown for example by the derailleur 165 in Figure IE, which in turn contributes to the overall drag of the bicycle. Furthermore, by moving part of the front derailleur assembly to a region behind the chain rings and crank, this ensures that even if part of the front derailleur assembly projects outwardly from the profile of the wheel mounting portion 530, airflow is already diverted around any projecting portions of the front derailleur assembly by the chain rings and crank, thereby minimising the drag created.

[0149] In the current example, the derailleur recess 540 includes two portions 541, 542, which can be used to house a derailleur servo 565 and derailleur battery 567 respectively. Alternatively, this may house part of a derailleur actuator, derailleur linkages and/or a derailleur housing in the case of cable operated derailleurs. It will be appreciated however that this is not essential and a single recess portion may be used. In this regard, the derailleur used in this example is a modified derailleur in which the servo 565 sits at the bottom of the chain guide 566, allowing the servo 565 to be positioned within the recess. However, it will be appreciated that this is not essential and that some benefit can be derived even with the servo and chain guide mounted as per traditional arrangements shown in Figure IE, with the battery contained within the recess 540. [0150] The wheel mounting portion 530 typically includes at least one stay 535 extending from the bottom bracket mounting 531 to the wheel mounting end 532. In this configuration, the stay 535 has an inner surface facing a rear wheel of the cycle in use and an opposing outer surface 533 facing away from the rear wheel, with the derailleur recess 540 being provided in the outer surface 533. In this case, at least part of the front derailleur assembly is substantially flush with the outer surface 533 of the stay to thereby assist in maintaining uninterrupted airflow, and hence reduce drag.

[0151] As previously described with respect to frame 100, stays 435, 535 of frames 400, 500 may additionally be designed having a profile that diverts airflow around part of a gear cassette mounted on a rear wheel of the cycle in use and/or part of a rear derailleur. By diverting airflow around the gear cassette and more typically the gear cassette and at least part of the rear derailleur, this reduces airflow incident on the gear cassette and/or rear derailleur, which it will be appreciated can contribute to significant drag in traditional arrangements.

[0152] Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers.

[0153] Persons skilled in the art will appreciate that numerous variations and modifications will become apparent. All such variations and modifications which become apparent to persons skilled in the art, should be considered to fall within the spirit and scope that the invention broadly appearing before described.