Front freewheel arrangement for bicycle.

Priority Cross-Reference

[0001] The present application claims priority from Australian patent application 2021900629 filed 5 March 2021 , the entire disclosure of which is hereby incorporated by reference into this specification.

Technical Field

[0002] The present invention relates to the field of bicycles and, more particularly, relates to a front freewheel arrangement for multi-geared bicycles. The invention particularly relates to a front freewheel adapter. The invention is particularly applicable for use on mountain bike racing bicycles and it will be convenient to hereinafter disclose the invention in relation to this exemplary application. Flowever, it is to be appreciated that the invention is not limited to that application and could be used for a variety of alternative types of bicycle such as road bicycles.

Background of Invention

[0003] The following discussion of the background to the invention is intended to facilitate an understanding of the invention. Flowever, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge as at the priority date of the application.

[0004] Conventional bicycle drivetrain systems transmit power from a rider’s feet to the rear wheel of the bicycle. In the field of geared bicycles, typical drivetrain systems include a pair of pedals rotatably connected to a pair of crank arms secured to a chainring (the drive gear) which is connected via a chain to a cogset (the driven gears) located on the rear wheel. In conventional systems, the cogset is connected to the rear wheel via a ratchet or ‘freewheel’ mechanism positioned on the rear wheel and configured to disengage or disconnect the rear wheel from the cogset when the rear wheel rotates faster in a forward direction than the cogset. The freewheel mechanism permits forward rotation of the rear wheel without inducing rotation in the cogset and subsequent drive of the chain and thereby enables the bicycle to coast in a forward direction without inducing rotation of the pedals or the rider’s feet.

[0005] Despite its ubiquity, there are a number of drawbacks associated with a freewheel system located on the rear wheel (also known as a ‘rear-freewheel system’). In particular, changing gears on the cogset requires rotation of the chain and cogset therefore requiring the rider to pedal in order to affect a gear shift. Whilst not a problem in all cycling applications, this requirement is a significant drawback in the sport of mountain bike racing in which it is not always possible (or would compromise stability) to rotate the pedals during tight cornering or during fast descents through technically challenging terrain. Consequently, bike riders using conventional bicycle drive trains will typically delay gear shifting during difficult descents or corners until the terrain allows for pedalling to resume. Whilst necessary to maintain stability, delaying gear changes is particularly undesirable during a time trial, head-to-head race, general training or recreation. It is common for the optimum gear in a a descent, entry to a corner or in a braking zone to be significantly different from the optimum gear at an exit of the descent (or into the next ascent), corner, or braking zone. Delaying gear changes until exit of this part of the terrain can therefore result in the rider resuming pedalling in a sub-optimum gear and resulting in lost time or in damaged equipment from gears changing while under the load of the riders resumed pedalling power. To pro-actively change gears, riders may ‘pseudo pedal’ for no other reason but to change gears, not to generate power, which compromises safety and the mental concentration of the rider.

[0006] In view of this issue, a number of mountain bike racing bicycles have been equipped with alternative drivetrain systems which permit gear shifting without the need to pedal. One such example is the use of planetary internal gear boxes such as the Rohloff Speedhub described in US Patent 6,258,005 or the Pinion transmission system as described in US patent publication 20160195184. However, internal gear box systems result in an undesirably large increase in bicycle weight, are not easily adaptable to common frame geometries, can be more complicated to maintain and are considerably more expensive than derailleur-type shifting systems of which the present invention is particularly concerned.

[0007] Another system permitting gear shifting without pedalling is known as the front-freewheel system (FFS) in which the rear wheel and cogset are fixed for mutual rotation and the freewheel clutch mechanism is located between the chainring and the drive crank. During coasting of an FFS bicycle, the cogset, chain and chainring rotate dependent on the rear wheel while the crank arms and pedals are not driven. The continuous rotation of the cogset enables the rider to change gears at any time while the rear wheel is rotating forwards. At such time the cranks can be rotating in any direction (forwards or backwards) or can be stationary. This enables the rider to select a desired gear during a descent, corner or braking zone, in anticipation of pedalling resumption, or to shift as normal while pedalling is occurring. FFS bicycles therefore provides the operator to shift pro-actively rather than reactively.

[0008] As well as being lighter and less costly than internal transmission systems, there are a number of additional advantages associated with FFS bicycle drivetrains. In particular, transferring the mass of the clutch mechanism from the rear wheel to the bottom bracket results in mass centralisation which can improve handling. By moving the clutch to the bottom bracket junction of the frame results in the possibility to greatly reduce the mass of the rear hub due to the simplification of moving parts in the rear wheel. Furthermore, where a bicycle is equipped with a rear-wheel suspension system (as is the case with most mountain bikes) transferring the mass of the clutch mechanism from the (unsprung) rear wheel to the (sprung) bicycle frame provides a reduction in unsprung mass resulting in improved suspension performance and overall bicycle handling. The handling and stability of FFS bicycles may also be improved during coasting (compared to non-FFS bicycles) as a result of an increased gyroscopic effect from the constantly rotating mass of the cogset, chain and chainring. Likewise, the constant rotation of the front chainring, chain and rear cogset means that less work is required by the rider when transitioning from coasting to pedalling as this mass is already moving in a radial fashion. In the same sense, the rear wheel is less likely to “jam” when riding over sharp edged objects such as rocks, as the momentum of the forward rotating chainring and chain aids in pulling the rear wheel over such obstacles. As mentioned, the rider is also able to pedal backwards, or “backpedal”, while changing gears. This may be advantageous for maintaining rider balance while decelerating harshly such as on a road bicycle braking for traffic lights while also down-shifting.

[0009] Another advantage associated with FFS mountain bike drivetrains is the reduction of pedal ‘kick-back’ or ‘feedback’. In a conventional bicycle with rear suspension, movement of the rear suspension causes the chain to transition between a loose and tight condition, and to ‘grow’ as the suspension compresses. The rider experiences this movement an undesirable ‘kick-back’ through the pedal due to the direct connection between the rear wheel and the cranks through the chain and chainring, even when pedalling is not occurring. In the same sense, the force applied from the rider’s legs through the pedals in order to combat the “kick-back” further effects suspension kinematics. In contrast, an FFS drivetrain isolates the pedals from the drive train when forward pedalling is not occurring. Consequently, during coasting of the bicycle, the cranks no longer interrupt suspension kinematics and kick-pack is reduced or eliminated. This results in improved suspension performance and rider satisfaction and the ability for bicycle manufactures/suspension designers the possibility to design a wholistic suspension design focused on optimum suspension performance of the bicycle alone, without having to factor in the dynamics of pedal kick-back.

[0010] FFS systems can also provide a number of advantages in the field of road bicycles. In particular, the ability to change gears while coasting and without requiring the rider to pedal merely to allow for a gear change.

[0011] Notwithstanding the advantages associated with FFS, particularly in the field of mountain bike racing, uptake of the technology has been limited. The cost to purchase a new bicycle configured with an FFS drivetrain is prohibitive for many mountain bike riders. An existing conversion system known as the ‘FIXR easy shift’ enables a conventional bicycle to be re-configured as an FFS bicycle. Flowever this system is prohibitive in that it requires the conventional crank arms, chainring, bottom- bracket bearings and rear hub to be replaced with new FFS-specific components. This contributes to increased cost of the conversion system and results in a time-consuming conversion process. Moreover, this system requires bicycle owners to abandon their high-quality, light-weight and expensive componentry for typically lower quality and unfamiliar equipment. Likewise, many professional and semi-professional riders with drivetrain sponsorship are barred from using drivetrain technology of this manner as it may compromise contractual agreements with current drivetrain sponsorships.

[0012] In view of the above, it is desirable to provide a new and improved front freewheel arrangement for a bicycle which addresses at least some of the above noted drawbacks in prior devices. [0013] Before turning to a summary of the invention, it is useful to provide an explanation of some of the terms that will be (and have been) used to define the spatial relationship of the various parts thereof. Spatial references throughout this specification will generally be based on an upstanding bicycle. Terms such as forward and rear will be understood in the context of a bicycle having a front and a rear end. Terms such as ‘forward rotation’ will be understood as the direction in which rotation occurs during forward movement of the bicycle or forward pedalling of the crankset. Terms such as ‘inboard’ and ‘outboard’ may be used with respect to the bicycle drivetrain. These terms will be understood as relative to the bicycle frame which will be understood to be on an ‘inboard’ side of the front freewheel adapter and the bicycle chainring. Components such as the bicycle cranks and pedals will be understood as ‘outboard’ of the chainring and front freewheel adapter. In this context, ‘inboard’ and ‘outboard’ may be used to describe the movement or position of various components either toward or away from the central axis of the bicycle.

Summary of Invention

[0014] According to the present invention there is provided a front freewheel adapter for a bicycle drivetrain which includes a crankset releasably connected to a chainring, the adapter being configured for installation between the crankset and the chainring to adapt the drivetrain for a front-freewheel configuration and the adapter including: a chainring connector member configured for releasable connection to the chainring; a crankset connector member configured for releasable connection to the bicycle crankset; a freewheel clutch connecting the chainring connector member and crankset connector member and permitting freewheeling of the chainring connector member relative to the crankset connector member, the chainring and crankset connector members each being releasably connected to the freewheel clutch and the chainring connector member being positionally adjustable relative to the freewheel clutch along a central axis of the adapter; a first locking arrangement for securing the chainring connector member relative to the freewheel clutch; and a second locking arrangement for securing the clutch in a desired position relative to the crankset connector member.

[0015] The present invention advantageously provides a front-freewheel adapter suitable for re-configuring a conventional bicycle as a front-freewheel bicycle without requiring replacement of the original bicycle crankset and chainring. Furthermore, it does not require the alteration of any existing componentry such as the bicycle frame or bottom bracket. In contrast to existing systems, the present invention is configured for installation between the original bicycle crankset and chainring. As discussed in the foregoing, this is particularly advantageous in the field of mountain bike racing in which it is highly undesirable to replace original (and typically expensive) componentry with lesser quality components provided in previous front-freewheel conversion systems. Furthermore, the releasable connections between the freewheel clutch and the chainring and crankset connector members provides the possibility for optimised chain alignment, and to adjust the adapter to achieve desired offset from other componentry. This provides improved versatility over existing products. The present invention therefore enables users to retain their original components which are often specifically selected for high-performance and/or light-weight attributes. Moreover, utilising original bicycle componentry reduces the cost of a front-freewheel conversion insofar as the conversion kit can be produced without replacement crankset and a replacement chainring.

[0016] The present invention is suitable for use with bicycle drivetrains in which the crankset is releasably connected to the chainring. This configuration is also known as the popular ‘direct mount’ system and typically involves the drive side crank arm or the cranks spindle having a spline that matches to a central opening on a direct mount spider or complete chainring. The spider member having a plurality of outwardly- extending connection arms (of a standard Bolt Circle Diameter) bolted to matching openings on the chainring. Direct mount cranksets have found increased popularity due to improved adaptability as compared to older systems in which the crank, spider and/or the chainring are integrally or permanently connected together. In contrast to these older systems, direct mount systems permit any one of the crank arms, spider or chainring to be replaced without requiring replacement of the other two components. The present invention utilises the adaptability of the direct mount configuration to provide a front-freewheel adapter which replaces the function of the spider member in connecting the crankset to the chainring whilst allowing a user to retain their original crank set and chainring.

[0017] The adaptability of the present invention is provided, in part, by the crankset connector member which is specifically configured for releasable connection to an existing bicycle crankset (crank arm or crank spindle). Bicycle cranksets suitable for direct mount cranksets typically include an externally splined projection on a proximal end of the drive crank or a splined projection on the crank spindle adjacent the drive side crank arm. The drive side crank arm having an internally threaded opening for receiving a pedal on a distal end of the drive crank. However, the size and configuring of splines on the proximal end of the crank arm or on the spindle can vary between brands and crankset models. Accordingly, in a form of the invention, the crankset connector member may be provided in a variety of configurations, each being suitable for operation with a particular style of crank arm or spindle interface. A user can thereby select the appropriate crankset connector member corresponding to the user’s existing brand or style of crank arm/spindle configuration.

[0018] The present invention is further advantageous in that both the chainring and crankset connector members are each releasably connected to the clutch. This enables interchange of different chainring and crankset connector members to suit different bicycle cranksets and chainrings. For example, the releasable connection between the crankset connector member and the clutch allows for a single clutch to be provided to a user but for the user to select from a variety of crankset connector members to suit their existing crankset. Furthermore, the chainring connector member is positionally adjustable relative to the clutch along a central axis of the adapter. This provides improved adaptability with various types of bicycle drivetrains and enables users to fine tune the position of the various components relative to one another. For example, to adjust the position of the clutch relative to the chainring.

[0019] In a form of the invention, the crankset connector member is positionally adjustable relative to the freewheel clutch along a central axis of the adapter and wherein the second locking arrangement allows the clutch to be secured in a desired position relative to the crankset connector member. This configuration enables adjustment of the relative position between the clutch and the crankset connector member. This mode of adjustment may enable use of the adapter with particular types of cranksets which would otherwise be incompatible with the adapter. For example, cranksets which require partial recession into the clutch in order for the drivetrain to be properly aligned.

[0020] The chainring connector member may be releasably connected to an outer race of the freewheel clutch. The chainring connector member may include a central opening which receives the outer race of the freewheel clutch. The central opening of the chainring connector member may be aligned with the central axis of the adapter. The chainring connector member, crankset connector member and the clutch may each include respective central openings which are concentric and with the central axis of the adapter extending through the centre of each central opening. Depending on the particular type of crankset on the user’s existing bicycle, the crankset connector member may connect to the crankset via the drive-side crank arm (i.e. the crank arm on the same side of the bicycle as the drive train) or the crank spindle. In either case, the crankset connector member may include an internally splined opening configured for engagement with an externally splined surface of the crankset. This form of the invention is suitable for use with many conventional cranksets in which the drive-side crank arm or crank spindle includes an externally splined boss configured for connection with an internally splined opening on a spider or solid chainring member. The adapter of the present invention is configured to engage with the crank arm or crank spindle in the same manner as the original spider or solid chainring member and may therefore be provided with a corresponding splined opening.

[0021] In a form of the invention, the crankset connector member includes an alignment projection abutting a portion of the clutch and facilitating alignment of the crankset connector member with the clutch. The alignment projection may comprise a lip. In a form of the invention, the lip is configured to abut a radial face of the clutch. In particular, the lip may be configured to abut an outboard radial face of the clutch. The lip may be located between the clutch and the drive side crank arm. In a form of the invention, abutment between the alignment projection and the clutch locates the crankset connector member in a predetermined position along the central axis, relative to the clutch. [0022] As noted in the foregoing, the crankset connector member is releasably connected to the clutch. This form of the invention is particularly advantageous in that a single clutch can be connected to a variety of different crank arm systems by selection of the appropriate the crank connector member configured for connection to the desired crank arm or spindle. The crankset connector member may be located within an inner race of the clutch. The crankset connector member may be releasably connected to an inner race of the clutch in which case the chainring connector member may be connected to an outer race of the clutch. In alternative embodiments, the arrangement can be reversed with the crankset connector member releasably connected to an outer race of the clutch and the chainring connector member connected to an inner race of the clutch. As noted above, the crankset connector member may preferably include a central splined opening for receiving a splined boss on a crank arm or crank spindle. The crankset connector member can include an annular outer surface configured to be received within an inner race of the clutch.

[0023] In a particular embodiment of the invention the crankset connector member includes an external connection formation configured for releasable engagement with a corresponding internal connection formation on the inner bearing race of the clutch. The internal and external connection formations can comprise any suitable connection formations facilitating releasable connection between the inner race of the clutch and the connector member. By way of example the internal and external connection formations could comprise internal and external splines, internal and external threads, corresponding grooves and recesses, corresponding bayonet fittings or a hex opening and hex protrusion which nest together. In an alternative form of the invention, the crankset connector member is connected to the inner race of the clutch via an interference fit or press fit. In another form of the invention, a connection formation is provided on only one of the connector member or clutch, for example one of the components may include a series of flexibly resilient gripping projections configured to deform and grip the opposing surface when the connector member is inserted within the inner race of the clutch.

[0024] In a particular form of the invention, the position of the clutch is adjustable along the adapter central axis relative to the crankset connector member and the second locking arrangement is configured to engage and secure the inner race of the clutch at a desired position, relative to the crankset connector member. It will be appreciated that, in use, the crankset connector member is connected to the crankset which is secured relative to the bicycle frame. The positional adjustment between the crankset connector member and the clutch therefore enables positional adjustment of the clutch, relative to the crankset connector member which (in a conventional bicycle) will normally be fixed, relative to the bicycle frame. The position of the clutch may be adjustable along the central axis of the adapter. The second locking arrangement may be configured to engage and secure the inner race of the clutch at a desired position, relative to the crankset connector member.

[0025] According to a particular embodiment of the invention, the crankset connector member may have an expandable outer diameter and the second locking arrangement is configured to increase the outer diameter of the crankset connector member in order to secure the clutch against movement, relative to the externally splined surface of the crankset connector member. The crankset connector member may have a resilient deformable configuration and the second locking arrangement may include an expansion member engageable with the crankset connector member to deformably expand the outer diameter of the crankset connector member. For example, the crankset connector member may be formed of a resilient material such as a steel C-shaped member which is resiliently expandable upon driving the expansion member into an opening between the ends of the C-shaped member.

[0026] The expansion member of the second locking arrangement may comprise a wedge member and the crankset connector member may comprise a discontinuous ring having an opening for receiving the wedge member. The wedge member may have a pair of opposite end faces for contacting a pair of corresponding end faces at the opening of the discontinuous ring, each pair of end faces being tapered with respect to the central axis and whereby insertion of the wedge member into the opening drives deformable expansion of the discontinuous ring in order to increase its outer diameter and secure the clutch relative to the discontinuous ring. The wedge member may comprise of multiply-tapered faces (i.e. faces which are tapered in more than one plane). For example, a face tapered relative to a radial direction and also tapered relative to a longitudinal direction of the adapter.

[0027] The expansion member may be driven into engagement with the crankset connection member (for example, driven into the opening of the discontinuous ring) by a wave washer located between the crankset connection member and a securing mechanism of the bicycle crankset, the wave washer being compressed by the securing mechanism. The wave washer may be configured to distribute approximately even pressure to the crankset connection member and to the expansion member. For example, the wave washer may be aligned such that a raised portion (or ‘wave’) of the wave washer contacts the expansion member. During compression of the wave washer by the securing mechanism, the raised portion of the wave washer may account for movement of the expansion member into the opening of the crankset connector member. In this way, when the securing mechanism is fully tightened, an approximately even clamping load may be applied to the crankset connector member and to the expansion member.

[0028] The wave washer may provide the correct “preload’ to the wedge and the crank connector member to ensure correct pressure is applied and the wedge operates uniformly when direct mount securing mechanism is tightened. A wedge “trough” or low point may be positioned in line with the wedge, so as to provide primary compression (compared to the remainder of the crankset connector) as the securing mechanism is tightened. The wave washer may consist of a fully enclosed loop, or have a slit to allow provision for the wedge to protrude, to allow for the primary contact.

[0029] For certain bicycle drivetrains it is noted that a wave washer may not necessarily be required. For example, some securing methods include multiple bolts at individual points around the peripheral edge of the adapter to secure the direct mount mechanism, instead of one “lock-nut” that spans the entire circumference of the adapter. In such a case, a wave washer may inhibit the effectiveness of multiple individual bolt securing method and, in one such example application, the need for a wave washer may be negated.

[0030] According to a particular form of the invention, the crankset connector portion may include internal and external connection formations which comprise of a male spline on the external axial face of the direct mount crankset adaptor and corresponding female splines on the internal axial face of the inner race of the clutch.

[0031] The crankset connector member may be held at an axial offset to the crankset via one or more tapered/multiple tapered wedges that act to expand/deform the outer diameter of the crankset connector into the inner race of the clutch as the wedge is forced into the crank connector member parallel axis C as direct mount securing method is tightened (usually via individual bolts, lock ring or via crank pressure method).

[0032] Simultaneously, the wedge(s) are urged radially outward into the inner bearing race of the clutch as the securing mechanism is applied. The narrow radial face of the wedge/wedges may sit shallower than crankset connectors face to allow space for the wedge to freely move inwards without axial interference and to appropriately expand surrounding crankset connector. The wedges wide radial face however may sit either flush or proud of crankset connector to receive primary force from securing method, so as to prioritize the expanding action of the wedge system.

[0033] The design of a splined interface with the clamping method of a tapered/multiple tapered wedge, or a multitude of wedges, gives the ability for the direct mount crankset connector member to be, like the chainring connector member, adjusted anywhere along its central axis to a finite offset, coexisting with the spiders offset, to achieve the any desired chain line per the crankset brand/frame being adapted to. The ability to adjust the offset of the direct mount crankset connector member gives the opportunity to maximise the space around the FFS and to increase adaptability to different crank brands. The present invention thereby is therefore compatible with a larger range of existing direct mount bicycle drive drains and provides improve customisation as compared to prior art devices.

[0034] As noted, the second locking arrangement may comprise a single expansion member such as a single wedge which is driven into a corresponding opening in the crankset connector member. According to a particular embodiment of the invention, the second locking arrangement may comprise a pair of expansion members. For example, a pair of wedges received within a pair of corresponding openings in the crankset connector member. In a particular embodiment, a first of the wedges is configured to be driven into an opening comprising a discontinuous section of the crankset connector member. The second of the wedges may be configured to be driven into a corresponding cut-away portion in the circumference of the crankset connector member. Insertion of the first wedge into the discontinuous section acts to drive apart opposing end faces of the crankset connector on either side of the discontinuous section to deformably increase the outer diameter of the crankset connector. Insertion of the second wedge into the cut-away portion does not have the effect of deforming the crankset connector, but instead provides a radial face which is flush with the first wedge to facilitate clamping of the wedges, for example by a wave washer or similar. The radial faces of the first and second wedges may protrude (i.e. sit proud of) the radial face of the crankset connector by, for example, 0.5mm. The first and second wedges may be provided on opposite sides of the crankset connector member e.g. 180° from one another. The securing mechanism (e.g. a wave washer) can therefore contact each of the wedges simultaneously and thereby balance the clamping load applied to the wedges and to the crankset connector member.

[0035] According to another form of the invention the internal and external connection formations comprise an internal thread on the inner race of the clutch and an external thread on an external surface of the crankset connector member. In use, a user may thereby conveniently screw or unscrew the desired direct mount crankset connector member (selected for compatibility with their style of crank arm/crank spindle) into the clutch. The thread may be configured or arranged such that forward pedalling drives the connector member in the tightening direction so as not to cause unscrewing of the threaded connection in use. The threaded engagement between the crankset connector member and the clutch provides a releasable connection and one in which the crankset connector member may typically not be positionally adjustable with respect to the clutch. For example, the adapter may typically be used with the thread on the crankset connector member screwed into the clutch to a fully tightened position. In other embodiments of the invention discussed subsequently, the engagement between the crankset connector member and the clutch may allow for relative positional adjustment between the clutch and crankset connector member.

[0036] The provision of a direct mount crankset connector member which can be releasably connected to the clutch enables a front-freewheel conversion kit to be provided with a single clutch suitable for a variety of different cranksets and their corresponding direct mount systems. This enables a user to re-use the front-freewheel clutch in the event they change crankset brand on their bicycle, by simply acquiring a new connector member compatible with the new crankset. Moreover, in some subsequently discussed embodiments of the invention, a releasably connected crankset connector can result in the clutch being adjusted finitely anywhere along inner bearing races central axis to provide the desired offset between the crank arm, the clutch and surrounding componentry.

[0037] The chainring connector member is releasably connected to the free wheel clutch. In a particular form of the invention the chainring connector member is releasably connected to an outer race of the clutch, for example an outer bearing race of the clutch. The chainring connector member may include a central opening which receives the outer race of the freewheel clutch.

[0038] In alternative embodiments, the chainring connector member may be connected to an inner race of the clutch (in which case the crank arm connector member may be connected to the outer race of the clutch).

[0039] The releasable connection between the chainring connector member and the clutch provides similar benefits as discussed above in relation to the releasable connection between the crankset connector member and the clutch. Namely improved adaptability which allows a user to replace the chainring to a different style, size or BCD by simply reconnecting their clutch to a new chainring connector member that is compatible with the new chainring.

[0040] The chainring connector member can be provided in a variety of shapes or configurations however, according to a particular form of the invention, the chainring connector member consists of a spider member having a plurality of connection arms extending outwardly for connection to the chainring. It will be convenient to hereinafter refer to the chainring connector member as a spider member although it will be appreciated that features of the chainring connector member discussed herein could be equally utilised with a non-spider chainring connector member (i.e. a chainring connector member that did not include a plurality of connection arms).

[0041] The spider member can, in some embodiments of the invention consist of a body which includes a central opening and a multitude of connection arms extending radially outwardly from the body for connection to the chainring. In this embodiment, the connecting arms would each have a bolt hole to match that of an existing chainring, of which may conform to industry standard Bolt Circle Diameter’s (BCD’s) which mostly consist of four or five connection arms of varying bolt hole diameters, depending on standard. [0042] The central opening may be sized to receive the outer bearing race of the clutch and the spider member can include the first locking arrangement for securing the clutch in position within the central opening of the spider member. That is, for securing the chainring connector member in a desired position relative to the freewheel clutch.

[0043] In some embodiments of the invention the locking arrangement can permit adjustment of the spider member position, relative to the clutch, along a central axis of the adapter. That is, the clutch may be secured to the bicycle via the crankset and the spider member (and chainring attached thereto) permitted to slide along the outer bearing race. This form of the invention advantageously permits a user to adjust the position of their chainring relative to the rest of the bicycle to align the chainring (and chain) for optimum performance.

[0044] The adapter of the present invention may further include a spacer of predetermined size fitted onto the outer race of the freewheel cutch to facilitate adjustment of the chainring connector member to a desired position, relative to the clutch. The spacer may be sized so as to set the relative position between the clutch and the chainring connector member. The spacer may comprise any suitable configuration. According to a particular embodiment, the spacer comprises a cup shaped member (termed an ‘offset cup’ below) which is fitted onto the outside of the freewheel clutch, opposing the spider member. In particular, the offset cup may be fitted to an inboard side of the freewheel clutch and includes a spacing portion extending a predetermined distance from the inboard side of the clutch to a distal end of the spacing portion and wherein the inboard side of the chainring connector member is abutted against the distal end of the spacing portion to achieve a desired position of the chainring connector member.

[0045] The offset cup may include internal splines for engaging with external splines on the outer race of the clutch. Offset cups of altering depth (i.e. varying length of the spacing portion) may be made available to suit the crankset brand of the user. The adapter could be sold with a number of offset cups of varying depth and corresponding to the most popular cranksets in the market. Alternatively, when purchasing the adapter, a user may select a particular offset cup size to suit their existing crankset. [0046] Fitting of the offset cup may advantageously align the spider member and account for the difference of respective offset along central axis of both the crankset direct mount adapter and the spider member. The offset cups are designed to press on to the inboard side of the outer bearing race of the clutch, or be held by the clamping of spider member, so when installed, the cups outboard radial face butts with the inboard radial face of the spider member to provide desired chain alignment as per the crank brand being utilized and to assist the chainring to run straight and true in relation to the rest of the clutch. The internal (e.g. female) splines of the offset cup align with the external (e.g. male) splines of the outer bearing race as with the spider’s interface.

[0047] The clutch may include one or more alignment indicia to facilitate adjustment of the spider member to a desired alignment. For example, the outer bearing race may include one or more markings corresponding to different chainring alignments. This aspect of the invention is particularly useful in the field of mountain bike and road racing where racing bicycles are highly tuned and minor adjustments can significantly impact gear changing. Moreover, this is another aspect of the invention not available in previous front-freewheel conversion kits.

[0048] In some embodiments the spider member is radially symmetrical so that it can be taken off by loosening a pinch bolt and ‘flipped’ about its axis to achieve a desired offset. For example, the spider connecting arms that would normally sit in front of the chainring and connect onto the frontside (i.e. outboard side) radial face of the chainring can be flipped so as be located on the back of the chainring and now connect to the backside (i.e. inboard side) radial face of the chainring. In the normal configuration, the spider arms are located on the outboard side of the chainring i.e. the chainring is between the spider arms and the bicycle frame. In the flipped configuration, the spider is relocated to the inboard side of the chainring i.e. between the bicycle frame and the chainring. The spider is flipped such that the same surface of the spider arms which was contacting the outboard side of the chainring is now contacting the inboard side of the chainring. According to this flipping procedure, the orientation of the chainring will typically remain unchanged and will therefore not interfere with the performance of chainrings having a unidirectional drive direction.

[0049] This procedure may therefore allow for the chainring to be moved further in the outboard direction by at least the width of the spider connecting arms and therefore increase the ‘positive’ offset of the chain line. This form of the invention is particularly advantageous as it provides the opportunity to achieve a positive offset chain line (found on some forms of mountain bikes and road bicycles).

[0050] The first locking arrangement may comprise a pinch bolt operable to reduce the size of the central opening of the chainring connector member (e.g. the spider member) for securing the chainring connector member onto the outer race of the freewheel clutch. In this form of the invention, the spider member may include a radial slit or break in its periphery thereby defining a pair of clamping arms capable of flexible deformation, that clamp together, reducing the spider members inner diameter when the pinch bolt tightens into the opposing “arm” of the spiders slit. In an alternative form of the invention, the locking arrangement may include a locking bolt extending through the spider member and operable to engage with a portion of the clutch to thereby lock the position of the spider member relative to the clutch. In a particular form of the invention, the first locking arrangement may comprise two radial slits or breaks and each slit or break having a corresponding pinch bolt. For example, the spider member may include a first radial slit with a first pinch bolt associated with the first radial slit and a second radial slit with a second pinch bolt associated with the second radial slit.

[0051] In a form of the invention, the chainring connector member has a two-piece configuration, the two pieces connected at radial slits, each radial slit associated with a corresponding pinch bolt operable to open or close the radial slit in order to increase or reduce the size of central opening of the chainring connector member.

[0052] In a particular form of the invention the central opening of the spider member includes an internally splined surface engaged with an externally splined surface of the clutch. This form of the invention advantageously reduces the chance of slippage occurring between the spider member and clutch and provides the opportunity to be uniformly and finitely adjusted along is central axis as to provide the desired chain line.

[0053] The chainring connection formation may be formed any suitable means to facilitate connection between the clutch and an original bicycle chainring. Many existing bicycles will include a chainring adapted for connection to a spider member in which case (and as noted above) the chainring connector member may, likewise, consist of a spider member. However, the chainring of a bicycle may be configured for a different type of connection to the crankset (crank arm/crank spindle), in which case the chainring connector member may be adapted to suit the particular connection.

[0054] For example, an original chainring can be configured for a more direct connection to a crank arm/crank spindle in which case there is no spider member connecting the crank arm/crank spindle to the chainring. In this type of configuration, a chainring may be provided with an internally splined central opening which engages with external splines on a crankset. The present invention may be configured for adaptability with this type of system. The freewheel clutch (also known as an overrunning clutch or one-way clutch) is disengaged when a driven portion rotates faster than a driving portion. In a particular form of the invention the clutch includes an inner bearing race configured for connection to the crank arm via the crank arm connector member and therefore corresponds to the driving portion of the clutch. In this form of the invention the clutch also includes an outer bearing race configured for connection to the chainring via the chainring connector member (i.e. spider member) and is therefore the driven portion of the clutch.

[0055] The clutch may include a ratcheting mechanism and thus may comprise a pawl clutch or a ratchet clutch plate design, or another form of engagement such as an electromagnetic clutch, or other form of engagement design. The clutch may comprise a trapped roller clutch or various other types of one-way bearing. In an alternative form of the invention the clutch comprises a sprag clutch. The provision of a sprag clutch advantageously provides a finite degree of rotational engagement an almost instantaneous clutch engagement and power transfer and therefore significantly reduces pedal backlash as compared to a pawl clutch that has a high degree of rotational engagement between engagement points. Force on the pedals from rider input is therefore almost immediately translated into chainring rotation with a sprag clutch as compared to the pawl clutches in conventional bicycle freewheels in which the crankset can undergo several degrees of free-rotation before the clutch is engaged. A sprag clutch provides the further advantage of having reduced running drag when disengaged (i.e. during bike coasting when the clutch is overrunning) as compared to a conventional pawl clutch. [0056] As noted, the use of a one way bearing, such as a sprag clutch provides near instant engagement/disengagement so there's no transitional delay between pedaling and coasting. This provides a more seamless riding experience and maximising the benefit from each gear stage before transitioning to the next. Moreover, the use of a sprag clutch provides near silent operation which increases rider awareness to the external environment and further enhances rider experience.

[0057] As discussed in the foregoing, FFS drivetrains fix the rear wheel to the rear cogset (also known as a cassette). This can be achieved by removing the rear freewheel altogether and installing a fixed hub which directly connects the cogset to the rear wheel. Alternatively, certain freehubs may be reconfigured with a locking member which permanently fixes the cassette to the rear wheel and thereby deactivates the function of the freewheel.

[0058] Some forms of the invention may therefore include a locking member suitable for locking a rear wheel to the rear cogset. In other forms of the invention this additional locking member component may not be required for example where the rear freewheel is being removed altogether. Accordingly, a particular form of the invention provides a front-freewheel conversion kit for converting a rear-freewheel bicycle to a front-freewheel bicycle including an adapter as discussed in the foregoing and a locking member configured for fixing rotation of the rear wheel to rotation of the bicycle drivetrain.

[0059] According to an aspect of the present invention there is provided a front freewheel adapter for a bicycle drivetrain which includes a crankset releasably connected to a chainring, the adapter being configured for installation between the crankset and the chainring to adapt the drivetrain for a front-freewheel configuration and the adapter including: a chainring connector member configured for releasable connection to the chainring; a crankset connector member configured for releasable connection to the bicycle crankset; a freewheel clutch connecting the chainring connector member and crankset connector member and permitting freewheeling of the chainring connector member relative to the crankset connector member, the chainring and crankset connector members each being releasably connected to the freewheel clutch and positionally adjustable relative to the freewheel clutch along a central axis of the adapter; a first locking arrangement for securing the chainring connector member in a desired position relative to the freewheel clutch; and a second locking arrangement for securing the clutch in a desired position relative to the crankset connector member.

[0060] The present invention also relates to a method of installing a front freewheel adapter according to any one of the preceding claims to convert a rear-freewheel bicycle to a front-freewheel bicycle, the method including the steps of:

• disconnecting a crankset and a chainring of the bicycle;

• connecting the chainring connector member to the bicycle chainring;

• connecting the bicycle crankset to the crankset connector member of the front freewheel adapter;

• fitting the adapter, chainring and crankset to the bicycle; and

• deactivating or removing the freewheel at the rear wheel of the bicycle to fix rotation of the rear wheel with rotation of the drivetrain.

[0061] The method may include the further step of adjusting the position of the chainring connector member relative to the clutch to achieve a desired chainring position relative to the bicycle frame. The method may include the further step of adjusting the position of the clutch relative to the crankset connector member to achieve a desired chainring position relative to the bicycle frame. These adjustments may be performed to, for example, achieve a desired chainring alignment. The adjustments may be performed visually, either by estimation of the user’s eye or by using visual indicia provided on a portion of the adapter. Alternatively, these adjustments can be achieved by using a spacer such as the above-discussed offset cup. [0062] The method may also include the additional steps of adjusting the position of both the clutch relative to the crankset connector member and the chainring connector member relative to the clutch. This may provide further adjustment in order to achieve desired chain alignment and clutch offset to increase adaptability to a wider range of cranksets/frame designs.

[0063] It will be appreciated that the present invention is also suitable for installation during construction of a brand-new bicycle and is therefore not only suitable for conversion of an existing rear-freewheel bicycle. In the field of mountain bike and other forms of bicycle racing it is common for racing bikes to be custom built by riders from brand new separate componentry and in this regard the front freewheel adapter according to the present invention may be selected as part of that componentry.

Brief Description of Drawings

[0064] In order that the invention may be more fully understood, some embodiments will now be described with reference to the figures in which:

[0065] Figure 1 illustrates a conventional downhill-type bicycle suitable for adaption to a front-freewheel arrangement using the present invention.

[0066] Figures 2 and 3 illustrate partially exploded views of a front freewheel adapter according to a first embodiment of the present invention;

[0067] Figure 4 illustrates an assembled view of the first embodiment front freewheel adapter shown in Figures 2 and 3;

[0068] Figure 5 illustrates a front freewheel adapter according to the first embodiment of the present invention when fitted to a bicycle chainring and crankset;

[0069] Figure 6 illustrates an exploded view of the first embodiment front freewheel adapter illustrated in Figures 2-5;

[0070] Figure 7 illustrates the front freewheel adapter of the first embodiment of the present invention when fitted to a bicycle drive train;

[0071] Figure 8 illustrates a partially exploded view of a second embodiment front freewheel adapter, according to the present invention; [0072] Figure 9 is a perspective view of a wedge member according to the second embodiment illustrated in Figure 8;

[0073] Figure 10 is a side sectional view of the second embodiment front freewheel adapter;

[0074] Figures 11 to 13 are various partial exploded views of the front freewheel adapter according to the second embodiment;

[0075] Figure 14 is an assembled view of the second embodiment front freewheel adapter;

[0076] Figure 15 is an exploded view of the second embodiment front freewheel adapter;

[0077] Figures 16 and 17 are side sectional and perspective views respectively of the front freewheel adapter with the chainring connector member in a conventional orientation;

[0078] Figures 18 and 19 are side sectional and perspective views respectively of the front freewheel adapter with the chainring connector member in a flipped orientation resulting in a reduced chain offset;

[0079] Figure 20 is an exploded view of a double wedge crankset connector member according to an alternative embodiment of the present invention;

[0080] Figure 21 is a perspective view of a double-slit chainring connector according to an alternative embodiment of the present invention;

[0081] Figure 22 is a perspective view of an alternative embodiment crankset connector member according to the present invention;

[0082] Figure 23 is a front view of the crankset connector member of Figure 22 fitted with a bicycle crank and installed within a front freewheel adaptor according to the present invention;

[0083] Figure 24 is a perspective view of an alternative embodiment crankset connector member according to the present invention; [0084] Figure 25 is a front view of the crankset connector member of Figure 24 assembled with a bicycle crank and installed within a front freewheel adaptor according to the present invention; and

Figure 26 is a perspective cut-away view of the assembly shown in Figure 25.

Detailed Description

[0085] Figure 1 illustrates a conventional downhill-type bicycle 10 having a freewheel mechanism (not shown) located at the hub of the rear wheel 12 and connecting the hub to a rear cogset consisting of cassette 14. A crankset 13 comprising crankset arms 16 and spindle 17 (of which only the drive-side crank arm 16 and end of 17 is visible in Figure 1 ) is releasably connected a spider member 18 which is releasably connected to a chainring 20. In use, rotation of crank arms 16 drives rotation of chainring 20 and thereby chain 22. Gear changes on cassette 14 are performed via a conventional derailleur-type arrangement 15 which requires rotation of chain 22. Accordingly, in this conventional arrangement, it is necessary for crank arms 16 to be rotated in order for chain 22 to shift cogs on cassette 14.

[0086] Figure 2 illustrates an embodiment of a front freewheel arrangement comprising a front freewheel adapter 24 according to the present invention. Adapter 24 includes chainring connector member comprising a chainring connector member 26, freewheel clutch 28 and crankset connector member comprising a crank arm/crank spindle connector member 30. Adapter 24 is suitable for reconfiguring bicycle 10 as a front-freewheel bicycle. When installed, adapter 24 connects the original crankset 13 (connecting to either crank arms 16 or spindle 17, depending on crankset brand) and to original chainring 20, thereby replacing original spider member 18 but enabling a user to retain and continue using their original crankset 13 (crank arms 16 and crank spindle 17) and chainring 20.

[0087] Crankset connector member 30 is generally annular and includes a plurality of protrusions 34 extending radially inwardly from the circumference of a central opening 32. Protrusions 34 are configured for complementary engagement with an externally splined surface at the proximal end of crank arm 16 or near the drive-side end of crank spindle 17. Crank connector member 30 is thereby specific to a particular type of bicycle crankset and by matching an original crank arm/crank spindle interface on a bicycle with the appropriate crankset connector member 30 enables adapter 24 to be used with a variety of bicycle crankset assemblies and drivetrains.

[0088] Crankset connector member 30 is configured for receipt within a central opening 36 in freewheel clutch 28. Crankset connector member 30 includes an external connection formation 38 configured for releasable engagement with a corresponding internal connection formation 42 on inner bearing race 40 of freewheel clutch 28. As illustrated in Figure 2 the external connection formation 38 and internal connection formation 42 consist of corresponding threaded surfaces which improve engagement between clutch 28 and crankset connector member 30

[0089] In other forms of the invention the internal and external connection formations may consist of corresponding threads, protrusions, recesses or any other suitable formation. It will also be appreciated that in some alternative forms of the invention the internal and external connection formations may be omitted and the crankset connector member 30 and clutch 28 may be connected via interference fit. In case of threaded interface between crankset connector 30 and clutch 28, the corresponding threaded surfaces may be arranged such that the pedalling torque through the crank connector member 30 is in the direction of tightening for the threaded engagement between connector member 30 and clutch 28.

[0090] Chainring connector member 26 is generally annular and includes a central opening 44 having internal splines 45 which are configured for engagement with external splines 46 on an outer bearing race 48 of clutch 28. Freewheel clutch 28 is received within central opening 44 and corresponding internal splines 45 and external splines 46 are engaged so as to, in use, fix rotation of chainring connector member 26 with the rotation of outer bearing race 48.

[0091] Chainring connector member 26 includes a locking arrangement 50 for securing the outer bearing race 48 and freewheel clutch 28 in position within the central opening 44 of chainring connector member 26. Locking arrangement 50 includes a slit or groove 52 in chainring connector member 26 which permits slight contraction of central opening 44 via resilient deformation of chainring connector member 26. Locking arrangement 50 further includes a pinch bolt 54 bridging slit 50 and configured to pinch slit 52 toward a closed position in which clutch 28 is clamped in position within central opening 44 by slightly decreasing the diameter of central opening 44. In use, the unscrewing or removal of pinch bolt 54 operates to unclamp clutch 28 from chainring connector member 26 as central opening 44 returns to its original size, slightly larger than outer diameter of bearing race 48. Locking arrangement 50 thereby provides a releasable connection between chainring connector member 26 and freewheel clutch 28.

[0092] Central openings 32, 36 and 44 of the crankset connector member 30, freewheel clutch 28 and chainring connector member 26 are concentric and adapter 24 includes a central axis C extending through the centre of adapter 24. Locking arrangement 50 permits positional adjustment of clutch 28 within the chainring connector member central opening 44 along central axis C of adapter 24. In use, crankset connector member 30 and freewheel clutch 28 are secured in position relative to the bicycle 10 via the connection between crankset connector member 30 and the crank arm 16 or crank spindle 17 (depending on brands direct mount design). Locking arrangement 50 allows the position of chainring connector member 26 (and the chainring 20 attached thereto) to be adjusted along central axis C. This is particularly advantageous insofar as it provides chain alignment adjustment i.e. adjusting the position of the chainring relative to cassette 14 and to the rest of bicycle 10. Clutch 28 may also include alignment indicia (not shown) for example a series of indentations, notches or other markings to assist a user in selecting a desired chain alignment. In a particular embodiment of the invention the outer bearing race will include 1 mm lines etched into the surface to operate in a similar manner to a metric ruler and permitting precise adjustment of chain and chainring alignment.

[0093] Turning to Figure 3, pinch bolt 54 is removed such that locking arrangement 50 is in an unlocked condition permitting insertion of clutch 28 (and crankset connector member 30 connected to clutch 28) into chainring connector member central opening 44. In transitioning to the locked condition, slit 52 can be slightly shut by tightening pinch bolt 54 to slightly decrease the diameter of central opening 44 - in its static condition, chainring connector 26 has a slightly larger internal diameter 44 than that of the external diameter of outer bearing race 48 so chainring connector 26 can accommodate receipt of clutch 28. Figure 4 illustrates locking arrangement 50 in a locked condition wherein clutch 28 has been inserted into central opening 44 and adjusted to a desired axial alignment. Pinch bolt 54 has then been screwed into threaded opening 56 in locking arrangement 50 thereby pinching slit 52 and clamping clutch 28 at the desired position.

[0094] Still referring to Figure 4, chainring connector member 26 includes outwardly-extending connection arms (of industry standard - usually four or five) 58 each having an opening 60 for mounting the chainring connector member to a pre existing bicycle chainring 20. Openings 60 are positioned to match corresponding openings in chainring 20.

[0095] Turning to Figure 5 there is illustrated an example of the front freewheel adapter member 24 mounted between a chainring 20 and crankset 13 which includes a pair of crank arms 16 (comprising a drive side crank 16a and a non drive side crank arm 16b) and a crank spindle 125. Openings 60 in the connection arms 58 of the chainring connector member 26 are aligned with corresponding openings in chainring 20 and mounting bolts (not shown in Figure 5) are used to connect chainring connector member 26 to chainring 20. Bicycle chainrings for mountain bikes are mostly provided in two sizes, a 94mm or 104mm bolt circle diameter, and road bicycles mostly in two sizes, 110mm and 130mm bolt circle diameter colloquially known as 94BCD,104BCD, 110BCD, 130BCD, etc. The chainring connector member 26 may therefore be provided in any of these sizes or other less common industry standards so as to permit mounting to the user’s existing chainring.

[0096] In the illustrated embodiment freewheel clutch 28 comprises a sprag clutch which will be appreciated by a person skilled in the art as including a plurality of ‘sprags’ between the inner and outer bearing races permitting relative rotation of the bearing races in one direction (a freewheeling or overrunning direction) but not in the reverse direction (the engaged direction). A sprag clutch provides instant or near-instant clutch engagement and power transfer when rotated in the engaged direction. This is particularly advantageous for use as a bicycle freewheel as compared to spring and pawl clutches used in conventional bicycle freewheels which can undergo several degrees of free-rotation in the engaged direction before the clutch is engaged. A sprag clutch is also desirable for use as a bicycle freewheel clutch due to reduced drag and also elimination of the clicking noise associated with the pawl clutch in conventional bicycle freewheels. It will, however be appreciated that the present invention is also suitable for use with a variety of alternative freewheel clutch arrangements including a traditional pawl clutch arrangement.

[0097] Figure 6 illustrates an exploded view of front wheel adapter 24. As discussed in the foregoing, chainring connector member 26 includes internal splines 45 45 configured for engagement with external splines 46 on outer bearing race 48. Clutch 28 includes a pair of retaining rings 64, dustcovers/bearing seals 66, bearings 68, retaining clips 70, circlips 72 and spacers 74. Clutch 28 also includes an annular sprag ring/cage 76. Inner bearing race 40 includes internal thread 42 configured for engaging external thread 38 on crankset connector member 30.

[0098] Figure 7 illustrates adapter 24 fitted between the crankset (in this example, attached to crank arms 16) and chainring 20 of a conventional bicycle. A pair of chain guides comprising an upper chain guide 78 and a lower chain guide 80 are used to reduce the chance of undesirable ‘chain drop’ in which chain 22 drops off chainring 20, however neither may be mandatory or may consist of other or varying embodiments. As illustrated, adapter 24 is installed between the bicycle’s original crankset 16 and the bicycle’s original chainring 20. The rider is thereby afforded the abovementioned advantages of a FFS bicycle whilst retaining their original crank arms and chainring and being offered the ability to adapt to a variety of chain lines, through the axial adjustability of both the crankset connector 30 and the chainring connector 26.

[0099] Figure 8 (and onwards) illustrates a front freewheel adapter 124 according to a second embodiment of the present invention. Adapter 124 has a central axis C and includes chainring connector member 126 which is equivalent to the chainring connector member 26 discussed above with reference to the first embodiment front freewheel adapter 24. Front freewheel adapter 124 includes a crankset connector member 130 which engages directly to the inner race 140 on a freewheel clutch 128 by use of external splines 139 on crankset connector member 130 and internal splines 142 on inner race 140. The crankset connector member 130 includes a central opening 121 with internal splines 134 which engage with external splines 119 on a boss 123 of crank arm 116 when boss 123 is inserted into central opening 121 .It will be appreciated that boss 123 is found on conventional crank arms and configured to connect the chainring to the crank arm. [0100] The front freewheel adapter 124 includes a first locking arrangement for securing the chainring connector member 126 in a desired position relative to the freewheel clutch 128. The first locking arrangement comprises a pinch bolt arrangement 150 which operates to secure the chainring connector member 126 onto the outer race of the freewheel clutch 128 in the same manner as is described above with respect to the first embodiment front freewheel adapter 24.

[0101] The front freewheel adapter 24 further includes a second locking arrangement configured to engage and secure the inner race 140 of the clutch 128 at a desired position, relative to the crankset connector member 130. As shown in Figure 8, the crankset connector member 130 has a discontinuous ring configuration with a radial opening 137 extending from the central opening 121. The second locking arrangement includes an expansion member comprising a wedge member 190 received within the radial opening 137 in the crankset connector member 130.

[0102] The wedge member 190 has a pair of opposite end faces 191 (one of which is shown in Figure 9) for contacting a pair of corresponding crankset connector end faces 192 (one of which is shown in Figure 8) at the opening of the discontinuous ring. Each pair of end faces 191 , 192 is tapered with respect to the central axis C such that insertion of the wedge member 190 into the radial opening 137 drives deformable expansion of the crankset connector member 130. Said expansion expands the outer diameter of the crankset connector member 130 and thereby locking external splines 139 with internal splines 142 and securing the crankset connector member 130 relative to clutch 128 in a desired position along axis C.

[0103] Figure 9 provides a closer perspective of the wedge member 190. The end faces 191 of the wedge member 190 are tapered by angle ‘x’ relative to central axis C and are also tapered radially by angle y. The taper provided by angle x relative to central axis C results in the wedge member 190 having an outer face 193 which is larger than the inner face 194. As shown in Figure 8, the larger outer face 193 is contacted by the wave washer 184 such that the wedge member 190 is received in the radial opening 137 with the inner smaller face 194 entering the opening 137 first. Insertion of the wedge member 190 into the opening 137 of the crankset connector member forces enlargement of the opening 137 when the wedge member 190 is moved into the opening 137 parallel with central axis C, as indicated by arrow ‘A’ in Figure 8. [0104] Referring again to Figure 8, the wedge member 137 is driven into engagement with the crankset connector member 130 by a wave washer 184 located between the crankset connector member 130 and a securing mechanism of the bicycle crankset (not shown). When the securing mechanism is tightened, the wave washer 184 is compressed by the securing mechanism. The wave washer 184 may be generally configured to distribute pressure evenly across the crankset connector member 130 and wedge member 190.

[0105] Figure 8 illustrates how the corresponding splines 139 and 142 may be held axially and radially dependant once desired offset is achieved via a tapered/multiple tapered wedge 190. In another embodiment, a plurality of wedge members may be used, where the plurality of wedge members simultaneously move inwards toward crankset connector member 130, parallel to axis C and outwards adjacent to axis C. As the wedge member(s) 190 move further inwards to crankset connector 130 and corresponding wedge end faces 191 make hard contact with crankset connector end faces 192, crankset connector 130’s diameter expands/deforms so as to clamp outwardly and remain in axial and radial dependence with inner bearing race 140, mating splines 139 with inner race’s splines 142. Furthermore, as wedge member 190 moves outwards adjacent to axis C, the wedge member itself also provides a similar outward clamping force to inner bearing race 140, mating splines 139 splines 142.

[0106] The wedge member 190 may be slightly thinner in the radial direction as compared to the crankset connector member. The is, the internal splines 193 of the wedge member 190 may be spaced further apart from central axis C when the wedge member 190 is inserted into the opening 137. This may allow room for the wedge 190 to move inwards into opening 137, along axis C, without any componentry interference and to appropriately expand surrounding crankset connector 130. The outer radial face 197 of the wedge member 190 (and the external splines of the wedge member 190) may sit proud of external splines 139 on the crankset connector 130 such that the wedge member 190’s external splines 198 receive prioritised force from the securing method, so as to prioritise the expanding action of the wedge system.

[0107] The crank connector member 130 is inserted at a desired axial offset inside clutch 128 (parallel to axis C) mating splines 139 with splines 142. The wedge member 190’s tapered wedge faces make contact with crank connector 130 tapered wedge faces 131 . As shown in Figure 8, a wave washer 184 is located adjacent to the crankset connector member 130 and to the wedge member 190. The wave washer 184 is positioned between the direct mount securing mechanism and the crankset connector member 130 such that compression of the wave washer 184 applies load to the crankset connector members 130 and the wedge member 190.

[0108] The wave washer 184 may be positioned so that a trough or low point of the wave washer 184 is positioned atop wedge member 190 so as to prioritise pressure to the outer wedge face 197 (more so than crankset connector 130) to ensure wedge member activates the expansion/deformation of the crankset connector member’s 130 outer diameter properly and uniformly. As the wedge member 190 move inwards parallel to central axis C, the wedge member end faces 191 make contact with crankset connector member end faces 192 causing radial expansion of crankset connector member 130 to clamp splines 139 outwardly into inner race spines 142 of the inner bearing race 140 of the clutch 128. This secures the crankset connector member 130 in axial and radial dependence with the inner bearing race 140. Furthermore, as the wedge member 190 moves radially outward relative to axis C, the wedge member 190 itself also provides said outward clamping force to inner bearing race 140 and splines 142. The corresponding crankset connector external splines 139 and inner bearing race internal splines 142 being held at an axial offset provides the ability for the desired offset of adapter 124 to be achieved. That is, the position of the clutch 128 (and the chainring connector member 126 secured to the clutch) can be adjusted relative to the position of the crankset connector member 130 which is secured to the crankarm 116.

[0109] Figure 10 illustrates a cross sectional view of adapter 124, showing the interface and connection with the crankset including the drive side crankarm 116 and with the chainring 120 and shows the connectivity of how the 3 main components and their sub-components are held in place to unify adapter 124. Figure 10 is illustrated with a crankset connector member 330 (illustrated in Figure 22) which is a variation of the crankset connector member 130 and in particular is provided with a peripheral lip 311 which is discussed in further detail below with respect to Figure 22. As shown, the lip 311 abuts a radial face of the clutch 128 and in particular abuts an edge of the inner bearing race 140. The lip 311 facilitates co-axial alignment of the crankset connector member relative to the clutch and reduces the possibility of the crankset connector member becoming tilted or skewed within the clutch during tightening of the locknut 118.

[0110] As shown, the chainring connection member 126 is engaged with the outer bearing race 148 of the clutch 128. The inner bearing race 140 is engaged with outer splines of the crankset connector member 130. The inner splines of the crankset connector member 130 are engaged with splines on the boss 123 of the drive side crank arm 116.

[0111] An example of where wave washer 184 is located and how the wave washer acts as a compression member to members 130 and 190 is provided in Figure 10. The wedge member 190 is sandwiched between crankset connector 130 and the wave washer 184. Figure 10 illustrates a crankset-securing mechanism comprising a locknut 118 (but may alternatively comprise an individual securing bolt or crank arm pressure). The locknut 118 secures to the crank arm 116 and applies compression to wave washer 184, the wave washer 184 in-turn pushes against the outer face 197 of the wedge member 190 and drives wedge 190 toward crankset connector member 130 and also radially outward into engagement with internal splines 142 on inner race 140 of the clutch 128. The locknut 118 may comprise the chainring-securing locknut from a bicycle crankset prior to the bicycle being adapted with the front freewheel system. That is, the locknut originally used to secure a direct-mount chainring to the crankset may be reused with the front freewheel adapter of the present invention as the locknut 118.

[0112] It is noted that in an alternative embodiment of the invention, the wave washer is not used and therefore the lock nut 118 directly contacts the wedge member 190 and the crankset connector member 130. For example, Figure 24 (discussed below) relates to a crankset connector member 430 with a raised portion configured for the locknut to apply even pressure to both sides of the crankset connector member and without the use of the wave washer.

[0113] Figure 11 provides an exploded view of the 3 main components of the present invention which are the crankset connector member 130, the clutch 128, and the chainring connector member 126. As illustrated, the chainring connector 130 is received within a central opening of the clutch 128 such that external splines 139 of the chainring connector member 130 engage with internal splines 142 on the inner bearing race 140 of clutch 128. The clutch 128 is received within a central opening 144 of the chainring connector member 126 such that external splines 146 of the outer bearing race 148 engage with internal splines 145 of the chainring connector member 126. It will be appreciated that the position of each of these three components is adjustable independently along the central axis C and thereby providing improved adaptability in order to achieve a desired chain line or chain offset. For example, the position of chainring connector member 126 may be slid along axis C relative to the clutch 128 and secured via the pinch bolt arrangement 150 when a desired position is achieved. Similarly, the crankset connector member 130 may be slid along axis C relative to the clutch 128 and secured in position along axis C via the wedge member 190 when the crankset securing mechanism is tightened.

[0114] Turning to Figure 12, the adapter 124 may further include an additional component configured to facilitate or assist in achieving a desired chain alignment via positional adjustment of the chainring connector member 126, relative to the clutch 128. To assist in this procedure, a spacer device 180 of predetermined size may be fitted to the outer bearing race 148. The spacer 180 includes an internally splined surface 182 having splines 183 configured to engage with external splines 146 of the outer bearing race 148. The spacer 180 may be sized so as to set the relative position between the clutch 128 and the chainring connector member 126.

[0115] The spacer 180 comprises a cup-shaped member fitted onto the outer bearing race of the clutch 128. The spacer 180 is fitted to an inboard side of the clutch 128 (i.e. the opposite side of the clutch 128 from the chainring). The spacer 180 includes a spacing portion 184 extending a predetermined size from the inboard side of the clutch 128 to a distal end 185 of the spacing portion 181 which is best shown in Figure 13. In use, the inboard side radial face 127 of the chainring connector member 126 is abutted against the distal end 185 of the spacing portion 181 of the spacer 180 to achieve a desired position of the chainring connector member 126. Turning briefly to Figure 15, spacer 180 includes an inner radial face 102 which, in use, abuts with an outer radial face 129 of the clutch 128 which is labelled in Figure 12. The spacer 180 is also illustrated in Figure 10, and turning thereto, the distal end 185 of spacing portion 181 of spacer device 180 is shown abutting the side of the chainring connector member 126. [0116] Referring to Figures 12 and 13, the spacer 180 is connected via internal female splines 183 to outer bearing races male splines 146. Spacer 180 is fitted to provide a desired chain offset and to ensure chainring connector 126 is true in chain alignment when chainring connector member 126 is abutted against the distal end 185 of the spacer 180.

[0117] The spacer 180 may be provided in various sizes (i.e. varying length of the spacing portion 181 ) to suit the crankset brand of the user. The adapter 124 could be sold with a number of spacers 180 of varying size (i.e. varying spacing portion length) and corresponding to the most popular cranksets in the market. Alternatively, when purchasing the adapter 124, a user might select a particular spacer 180 size to suit their existing crankset. Popular offsets (measured from the inside of the crank arm to the outside face of the chainring 20) are 0, 3 and 6mm - however it is appreciated that there are other offsets used, and thus spacer 180 may come in varying sizes to accommodate these less common chain lines.

[0118] The offset cup 180 may be held in place by being pressed onto outer bearing race 148 or, alternatively, may be held in place by fitting under a lip (not shown) in chainring connector member 126 which is under compression of chainring connector member 126 as the pinch bolt arrangement 150 is tightened. In some embodiments, the offset cup 180 may be held in place by slipping under a groove in the backside of chainring connector 126, so as when pinch bolt 154 is tightened and the chainring connector member 126 diameter is decreased, the spacer 180 is radially compressed and held in place.

[0119] Figure 12 also illustrates the arrangement of the chainring 120 with respect to the chainring connector member 126. In particular, the chainring connector member 126 includes a seat 132 upon which the chainring 120 is positioned. The seat 132 is orientated approximately parallel with central axis C and may be provided with a width approximately equal to the width of a standard chainring.

[0120] Figure 13 shows the spacer 180 placed at the inboard side (i.e. the frame side) of the clutch 128 (mating spacer splines 183 with outer bearing race splines 146). The chainring connector member 126 and pinch bolt 154 are shown exploded from the rest of the adapter 124. The spacer 180 presses/clips over outer bearing race 148 mating spacer splines 183 with outer bearing race splines 146. The spacer 180 is designed per desired chain offset (usually 0mm, 3mm, 6mm) for each crank brand/model and thus is provided in varying sizes to account for the particular chain line required. The length of the spacing portion 181 corresponds to the desired difference in the offset of crank connector 130 and chainring connector 126, parallel to axis C.

[0121] The desired length of the spacing portion 181 may be calculated by the following formula: Desired spacer length (i.e. spacing portion 181 length) = CW (clutch width) - CO (chain line offset) - CRSW (chainring seat width) - CD (crank depression). The clutch width CW and Chainring seat width CRSW will be appreciated as the respective widths of the clutch 128 and the chainring seat 132 on the chainring connector member 126 (shown in Figure 10) along the central axis C. The Chain line offset CO is defined as the distance along central axis C from the front face (i.e. the outboard side) of the chainring to the inside face (i.e. inboard side) of the crank arm. The crank depression CD is defined as the distance along central axis C which the crank arm is depressed into the clutch 128, as is the case for particular types of crank arms which include a protrusion that would conventionally be depressed into the chainring 120. It will be appreciated that CW, CRSW and CD will be physical dimensions of the particular components being used and will therefore be constant. The desired chain line offset CO may vary depending on user preference.

[0122] By way of example, the clutch 128 used with the present invention may typically have a width of 18mm. In an example where a chain line offset of 3mm is desired and the user is using a chainring seat width (and a chainring) having a width 5mm and a crank with a 4mm depression, the length of the spacing portion 181 of the spacer 180 will be equal to 18mm - 3mm - 5mm - 4mm = 6mm.

[0123] Figure 14 illustrates an assembled view of adapter 124 when viewed from the outboard (i.e. the chainring side). The crankset connector member 130 and wedge member 190 can be seen located within the inner bearing race 140 of the clutch 128 which is located within the chainring connector member 126. Figure 14 illustrates a secured configuration where the pinch bolt arrangement 150 is tightened to secure the position of the chainring connector member 126 relative to the clutch 128 and also where the wedge member 190 has expanded the chainring connector member 130 so as to secure the position of the clutch 128 relative to the chainring connector member 126.

[0124] Figure 15 illustrates an exploded view of front wheel adapter 124. From top to bottom of Figure 15 there is illustrated the wave washer 184, the wedge member 190, the crankset connector member 130, the spacer 180, a dust cover 166, a bearing 168, the outer bearing race 148, the inner bearing race 140, the sprang ring 176, another dust cover 166, the chainring connector member 146 and the accompanying pinch bolt 154.

[0125] Figures 16 - 19 illustrate a potential configuration of the present invention in which the chainring connector member 126 is fitted to the clutch 128 in a ‘flipped’ configuration in order to achieve a differing chain line characteristic, such as negative (or more outboard) chain line. It should also be noted that chainring connector member can be adjusted axially, or flipped, without the aid of offset cup 180 if proprietary or less common chain line is to be sought.

[0126] Figures 16 and 17 illustrate a ‘conventional’ installation of adapter 124 in a side and perspective view respectively. The chainring in Figure 17 has been removed for illustrated purposes. The chainring connection member 124 includes a circular seat 132 onto which the chainring 120 is fitted and secured to the connection arms 158. The configuration shown in Figures 16 and 17 is similar to Figures 5, 8 and 10 in that the chainring connector member 126 is orientated with the circular seat 132 located inwardly of the connection arms 158. As shown in Figure 16, this results in the chainring 120 being spaced inwardly by approximately the width of the connection arms 158 and which, in the illustrated embodiment is 6mm. This is known as a 6mm ‘offset’ in that the bicycle chain is spaced 6mm from the inner side of the crank arm 116.

[0127] In Figures 18 and 19, the orientation of the chainring connector 126 (with the chainring 120 connected thereto) has been flipped (i.e. reversed) such that the connection arms 158 are positioned inwardly of the circular seat 132 onto which the chainring 120 is fitted. The result is that the chainring 120 is positioned outwardly (i.e. moved in the outboard direction as compared to the 6mm offset shown in Figures 16 and 17). The chainring 120 is moved outwardly by an amount equal to the thickness of the chainring connection member minus the thickness of the chainring. In the illustrated embodiment this is also equal to the thickness of the connection arms 158 taken in the direction of the central axis. In the particular example illustrated in Figure 18, this achieves a 0mm offset i.e. the chainring 120 is 0mm from the inner side of the crank arm 116.

[0128] The invention thereby allows a significant user adjustment of preferred chain offset via movement of the chainring connector member 126 relative to the clutch 128 and then also potential flipping of the chainring connector member 126 in order to achieve larger offset adjustment.

[0129] The spacer 180 may also be flipped radially, either respectively or independently to chainring connector member 126, to achieve desired the chain alignment.

[0130] It is appreciated that clutch 128 is itself symmetrical and can be “flipped” independently of the other 2 main components, so that the bicycle would work in reverse. In other applications of the freewheel adapter, the chainring connector member and crankset connector member may be flipped relative to the clutch so as to permit installation of the adapter in a ‘left hand drive’ configuration on the left side of the bicycle frame. This configuration may be used in some speciality bicycle builds where a bicycle gearing arrangement is assembled on the left of the bicycle frame and connects to a drivetrain on the right side of the bicycle frame which connects to a gear on the rear hub for driving the rear wheel.

[0131] It will be appreciated that in particular embodiments of the invention, only part of a wave washer (for example a segment or strip of a wave washer as opposed to an entire wave washer) may be used instead of a wave washer. In other alternative embodiments, a wave washer may be omitted altogether.

[0132] It will be appreciated that a single wedge member 190 or potentially a plurality of wedge members could be used in the present invention. For example, turning to Figure 20, there is illustrated an alternative embodiment of a crankset connector member 230 first wedge member 290 in use with a second wedge member comprising a wedge-shaped insert 295 insertable into a cut-away 235 in the crankset connector member 230. The cut-away 235 is located radially opposite to the opening 237 in the crankset connector member 230 which is configured to receive the first wedge member 290. The wedge-shaped insert 295 and the wedge member 290 each include radial faces 299 and 297 respectively which face away from the crankset connector member 230 and which, in use, are contacted/compressed by a wave- washer or other clamping mechanism in order to drive the wedge-insert 295 and the wedge member 290 into the corresponding cut-away 235 and opening 237 in the crankset connector member.

[0133] The crankset connector member 230 includes a radial face 238. In use, the radial faces 299 and 297 of the wedge-insert 295 and wedge member 290 protrude from the radial face 238 of the crankset connector member 230. The radial faces 299 and 291 of the wedge-insert 295 and wedge member 290 provide clamping faces for the securing mechanism of the bicycle crankset. That is, when the securing mechanism is tightened, the wedge-insert 295 and wedge member 290 are compressed and consequentially driven radially outwardly into engagement with internal splines of the clutch inner race.

[0134] It will be appreciated from Figure 20 that insertion of wedge member 290 into the opening 237 acts to drive apart opposing end faces 292 of the crankset connector 230 on either side of the opening 237 to deformably increase the outer diameter of the crankset connector 230. Insertion of the wedge-shaped insert 295 into the cut-away 235 does not have the effect of deforming the crankset connector 230, but instead provides a clamping face 299 which is flush or aligned or co-planar with the clamping face 297 of the wedge member 290. The clamping faces 299, 297 sit proud of the radial face 238 by an equal distance so as to provide an even face for the securing mechanism to make contact with. This facilitates clamping of the wedges 295, 290 for example by a wave washer or similar.

[0135] Figure 21 illustrates an alternative embodiment chainring connector 226 which is similar in configuration to the above discussed chainring connectors 26, 126 but includes a pair of radial slits 252 which comprise a break. The chainring connector member 226 thereby has a two-piece configuration comprising a first piece 226 and a second piece 226b. Each slit 252 is associated with a respective pinch bolt 254 (only one of which is visible in Figure 21 ). Loosening of the two pinch bolts 254 enables radial slits 252 to be enlarged in order to increase the size of the central opening 244 of the chainring connector member 226 which facilitates placement over the external splines 46, 146 of the freewheel clutch 28, 128. Tightening of the pinch bolts 252 reduces or closes the slits 252 in order to reduce the size of the central opening 244 and secure the chainring connector member 226 onto the clutch 28, 128. The pair of slits 252 and pinch bolts 254 provide a first locking arrangement for securing the chainring connector member 226 in a desired position relative to the freewheel clutch 28, 128. Operation of the first locking arrangement allows for positional adjustment of the chainring connector member 226 (and the chainring connected thereto) and which therefore enables adjustment of the offset between the chainring and the drive side crank arm.

[0136] Figure 22 illustrates an alternative embodiment crankset connector member 330 which comprises a C-shaped portion 319 and a removable wedge member 290 received within the C-shaped portion 319. The C-shaped portion 319 includes a circumferential lip 311 for abutting the clutch. The lip 311 facilitates proper positioning and orientation of the C-shaped portion 319 by ensuring that the C-shaped portion 319 is axially aligned with the clutch.

[0137] In the illustrated embodiment in Figure 22, the connector member 330 is configured for use with SRAM™ type direct mount standards which include bolt fixtures. The connector member 330 therefore includes three bolt openings 321 including two openings 321 on the C-shaped portion and one opening 321 on the wedge member 290. The openings 321 are configured to receive bolts which engage with SRAM cranksets.

[0138] Figure 23 illustrates the crankset connector member 330 fitted with a bicycle crankset 313 of the SRAM™ type. The internal splines 334 of the connector member 330 are engaged with external splines 319 on a crank boss 323 of a crankset 313. The external splines 339 of the crankset connector member 330 are engaged with internal splines 342 on the clutch inner bearing race 340 of the clutch 328. Only the inner bearing race 340 is visible in Figure 23 with the rest of the clutch being obscured by a spacer cup 380 which is equivalent in configuration to spacer cup 180 shown in Figures 12 and 13 is also visible in Figure 23.

[0139] Figure 24 illustrates a further embodiment crankset connector member 430 configured for use with Shimano™ type direct mount standards. The crankset connector member 430 includes a removable wedge 490 and a lip 411 which is equivalent in function to the lip 311 described above with reference to Figures 22 and 23. The crankset connector member 430 includes a radial face 438 which includes a raised portion 491 located radially opposite (i.e. on the opposite side of the central axis) from the wedge opening 437 and the wedge 490.

[0140] The raised portion 491 includes a radial face 499 which is raised from the radial face 438 by approximately the same amount that the radial face 497 of the wedge member 490 is raised from the radial face 438 of the crankset connector member 430, when the wedge member 490 is inserted into opening 437. In this manner, the radial face 499 of the raised portion 491 and radial face 497 of the wedge member 490 are approximately aligned and provide aligned clamping faces for a securing mechanism such as a locknut to clamp against when the crankset is assembled and tightened.

[0141] Referring to Figures 22 and 24, the crankset connector members 330, 430 each include a pair of openings 307, 407 configured as tool engagement points to facilitate removal of the crankset connector member from the clutch. These openings 307, 307 are engageable by a tool such as needle-nose pliers or the like in order to manually reduce the diameter of the crankset connector member 330, 430 which might become resistant to removal over time and particularly with prolonged exposure to grease and in the event of exposure to dirt and grime.

[0142] Figure 25 illustrates the crankset connector member 430 (and the whole of a front freewheel adapter 424 according to the present invention) fitted with a bicycle crankset 413 of the Shimano™ type. A chainring 420 is also shown fitted to the chainring connector member 426. In use, a locknut (not shown) is engaged with the drive side crank arm 416 and which contacts the wedge member 490 and raised portion 491. The crankset connector member 430 is therefore sandwiched and clamped between the locknut and the drive side crank arm 416. The locknut drives the wedge member 490 into the opening 437 of the crankset connector member 430 causing radial expansion of the crankset connector member which secures the crankset connector member against relative movement along the central axis between the crankset connector member 430 and the clutch.

[0143] Figure 26 is a perspective cut-away view of the assembly shown in Figure 25. Figure 26 shows part of the crankset 413 which includes a drive side crank arm 416 and a crank spindle 417. The crank arm 416 includes a splined boss 423 with external splines 419 engaged with internal splines 434 on the crankset connector member 430. The lip 411 of the crankset connector member 430 abuts an outboard radial face of the clutch 428 and in particular of the inner bearing race 440. The lip 411 facilitates alignment between the crankset connector member 430 and the clutch 428.

[0144] The lip 411 also provides predetermined relative positioning along the central axis of the adapter between the crankset connector member 430 and the clutch 428. In the illustrated embodiment, the predetermined relative positioning is such that an outboard radial face of the crankset connector member 430 is approximately flush with an outboard radial face of the clutch 428. However, it will be appreciated that other relative positions could be desired and the lip 411 configured accordingly. For example, the lip may be configured to locate the crankset connector member further inboard of the clutch such that the crank arm 416 was moved toward or partially received inside the clutch 428.

[0145] In other embodiments of the invention the crankset connector member may be provided without a lip (for example, crankset connector member 230 illustrated in Figure 20) and may therefore be permitted for positional adjustment along the central axis of the adapter to a preferred relative position within the clutch.

[0146] Still referring to Figure 26, the crankset connector member 430 external splines 439 (not visible in Figure 26) are engaged with internal splines 442 of the inner bearing race 440 of the clutch 428. An externally threated locknut (not shown) engages with an internal thread in the crank arm 416 to clamp the crankset connector member 430 to the crank arm 416. The assembly of the locknut, crankset connector member 430, crank arm 416 and spindle 417 is secured in position relative to the clutch 428 by operation of the wedge member 490 which is shown partially cutaway in Figure 26. As discussed in the foregoing, the locknut compresses the wedge member 490 into its corresponding opening 437 (shown in Figure 24) to cause radial expansion of the crankset connector member 430 which thereby prevents relative movement along the central axis between the crankset connector member 430 and the clutch 428.

[0147] The offset cup 480 is fitted over the inboard side of the clutch 428 to set the relative positioning between the chainring connector member 426 and the clutch 428. Once the desired relative position between the chainring connector member 426 and the clutch 428 is achieved, the pinch bolts (not shown in Figure 26) of the chainring connector member 426 are tightened to secure the chainring connector member 426 onto the outer bearing race 448 of the clutch 428.

[0148] The chainring 420 is fitted to the connection arms 548 of the chainring connector member 426.

[0149] Referring to the above-discussed Figures and reference numerals, a particular method for installing front freewheel adapter 24,124 to convert rear-freewheel bicycle 10 to a front-freewheel bicycle, is as follows:

1 ) Remove chain 22 from chainring 20, 120 and remove front chain guide - noting the respective chain off-set (usually 0mm, 3mm or 6mm)

2) Remove spindle/crank bolt and remove crank arms 16, 116 and in some cases spindle 17, 117 from bike 10.

3) Remove chainring 20, 120 and chainring bolts 62 from the chainring connection member 26, 126 (aka the ‘spider’) - note which BCD chainring/spider combination is present.

4) Remove the Direct Mount securing system (depending on crank brand this may consist of a singular lock-nut, a multitude of securing bolts or pressure of drive side crank arm) and disconnect spider 26, 26 or complete chainring from the drive-side direct mount splines located on crank arm 16, 116 or spindle 17, 117.

5) Fit the desired spacer cup 180 (depending on chain alignment for appropriate crank brand/offset configuration) to the backside of the clutch 28, 128, mating spacer cup splines 183 with outer bearing face splines 146 so that spacer cup 180 inner radial face 102 mates with the outer radial face 129 of the clutch 128.

6) Fit desired chainring connector member 26, 126 (of industry standard BCD) to the freewheel clutch 28, 128 by loosening pinch bolt 54, 154 and sliding the chainring connector member 26, 126 onto the external splines 46, 146 of the freewheel clutch 28, 128 - chainring connector member 26, 126 should be facing the appropriate way (flipped or not flipped) according to the desired offset and depicted by the spacer cup used in step 5. Once secure and appropriate offset is achieved by abutting the chainring connector member 26 126 inner radial face 127 with outer radial edge 185 of spacer cup 180, tighten pinch bolt 54, 154 with use of alien wrench/socket. ) Connect chainring 20, 120 to the chainring connector member 26, 126 using the removed chainring bolts 62 from step 3. ) Fit the crankset connector 30, 130 to the cranksets direct mount system as per crank brand, located on drive side crank arm 16, 116 or spindle 17, 117. Match the male crank direct mount to the female mount in crank arm connector member (i.e. opening 32). It is not secure at this point. ) Slide the freewheel clutch 128 onto the crankset connector member 130 engaging the corresponding external splines 139 and internal splines 142 of both parts. 0) Insert the corresponding crankset connector’s wedge(s) 190 into the radial opening 137 of the crankset connector member 130. 1 ) Depending on brand, wave washer 184 may be added between the crankset connector 30, 130 and the direct mounts securing system (respective brands lock- ring, securing bolts or crank arm). Note the wave washer 184 should be placed so that a lower point, or “trough” of a wave is positioned so as to make contact with wedge 190’s outside radial face 193, so when securing system is tightened the wave washer 184 provides prioritised pressure to the wedge member 190 to drive it inward parallel to central axis C to expand/deform crankset connector member 130, and to also provide even distribution of lateral compression to the face of crankset connector member 130. This will also activate wedge member 190 to move radially outward relative to axis C and provide radially outward clamping pressure to inner bearing race 140. Wave washer 184 may be provided with a slit 186 (labelled in Figure 8) whereby the slit 186 sits either side of wedge member 190to leave wedge face 193 exposed to direct pressure from securing method. Some brand of components may negate the use of wave washer 184 2) Secure crankset connector 130 by tightening the Direct Mount securing system (via respective brands lock-ring, securing bolts or by crank arm compression). By tightening this system, the wedge member 190 is compressed along central axis C and makes contact end faces 192 on crankset connector member 130. The wedge member 190 may sit either flush or proud of the crankset connector member 130, such that wave washer 184 or crank securing system makes hard contact with wedge member 190 as it tightens, moving the wedge member 190 inward parallel to central axis C and thereby expanding/deforming crankset connector member 130 radially outwardly and into tighter engagement with inner bearing race 140. The multiple tapered face of wedge member 190 means that, as the securing mechanism is tightened, the wedge 200 drives further inwards parallel to axis C (as above), but also radially outward relative to central axis C (due to the corresponding multiple taper in crankset connector member face 192), as the wedge member face 191 make harder contact with crankset connector member faces 192. The crankset connector member 130 respectively expands outwards (increasing its diameter) and into the corresponding inner race splines 142 of the clutch 128 to create a clamping fit to eliminate any axial or radial movement between the clutch 128 and the crankset connector member 130. ) Secure left and right crank arms 16, 116 by reassembling their interface with the spindle 17, 117 (reinsert spindle 17, 117 inside bike’s bottom bracket if removed) as per the original bicycle configuration and refit the chain 22 to the chainring 20, 120. ) Fix rear wheel 12 to cassette 14. This may be performed by replacing the rear freewheel with a locked hub. Alternatively, certain brands may permit locking of a freehub via the following procedure: Remove the wheel from the bicycle and remove freehub. Remove the two clutch plates and replace with a splined locking member to span between the hub body and the driver. The splined locking member slides into the mating female splines of the driver and the hub body to inhibit independent rotation. Insert the driver/freehub back in its original position with the new driver/freehub spacer properly seated in the splines and spanning between the hub body and the driver. Ensure the driver/freehub is properly seated axially all the way to the hub body so the spacer is totally concealed (as it was originally). Proceed to secure as original with appropriate end caps and reinstall back into the bicycles rear dropouts. Other locking techniques may come in the form fixing the cassette 14 to the wheel 12 spokes or hub flange by the method of an adapter or ties to inhibit independent rotation between the cassette and the hub.

[0150] The above procedure is included to exemplify one possible method of installing front freewheel adapter 24, 124 however it will be appreciated that the above procedure may vary depending on the particular drive train configuration and component brand.

[0151] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is understood that the invention includes all such variations and modifications which fall within the spirit and scope of the present invention.

[0152] Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other feature, integer, step, component or group thereof.