WO2003095042A2

WO2003095042A2 - Kiteboard

Info

Publication number: WO2003095042A2
Application number: PCT/GB2003/001978
Authority: WO
Inventors: David Morris; Mark Daniels
Original assignee: George Anthony Limited
Priority date: 2002-05-08
Filing date: 2003-05-08
Publication date: 2003-11-20
Also published as: GB0210452D0; AU2003227916A1; WO2003095042A3; GB0426927D0; GB2404870A

Abstract

A kiteboard comprising a platform on which a person stands in use, a pair of ground engaging members and an axle between the pair of ground engaging members, wherein the platform is located between the axle and the ground in use.

Description

Kiteboard

This invention relates to kiteboards and wheels and more particularly to wheeled kiteboards and wheels for kiteboards.

It is known to use kites to power three wheeled stainless steel framed carts commonly known as "buggies". The kites used to power such "buggies" are often ram-air kites that form a wing shape and are inflated by air being rammed into a leading edge through mesh or holes. The use of these kites to power buggies has become a popular leisure and sporting activity.

It is also known to use kites to pull surfboards across water in the sport of "kitesurfing" or "kiteboarding". Specialist kites have been developed for use with surfboards such as inflatable kites with a single skin, comprising air bladders for inflation, which hold their shape. Similarly specialist surfboards known as kiteboards have been developed better suited to the needs of a kite surfer.

Kite surfers have to take great consideration of safety and this is a hindrance to learning and limits the frequency with which the activity can be carried out. When kite surfing in the sea a kite surfer must not sail in offshore winds or go out in conditions beyond his capabilities and has to take into consideration tide time tables. Lakes and pools can also be used but usually have natural obstacles to be aware of such as trees, staging and fishermen and also a kite surfer may have to abide to time slots as lakes and pools are mostly used by water-ski, windsurfing and sailing clubs. Kite surfers therefore have only a limited number of suitable locations and are dependent on weather conditions so that the frequency with which they can practise is low in most counties. Indeed kite surfers are usually also advised not to practise on their own.

It is known for kitesurfers to attempt to use skateboards or mountainboards, which are slightly larger than skateboards and have pneumatic tyres, in combination with kites as a practise tool. Mountainboards and skateboards are designed to be used on firm surfaces powered down hill by gravity and steered by weight distribution and this is what they are most suitable for. This means they have a very different feel to a conventional kiteboard which uses a kite and board in a similar manner to a water skier uses a motorboat and skis, the kite pulling the surfer along until they are fast enough to skim over the water. Static balancing on an skateboard, designed for tricks and therefore designed to be relatively unstable, that frequently sticks in soft sand while trying to fly a kite is very difficult, the more so because the power from the kite applies to the torso and can pull the user off the board. The wheels used on skateboards and mountainboards are also not suitable for soft sand on which many surfers like to practise, partly to cushion them if they fall.

It is an object of the invention to provide a kiteboard which can be used on land , such as soft sand, and which overcomes some of the problems of using skate or mountainboards in combination with a kite.

It is another object of the invention to provide a wheel designed so that different tyres can be quickly changed for different surfaces.

According to a first aspect of the invention there is provided a kiteboard comprising a platform on which a person stands in use, a pair of ground engaging members and an axle between the pair of ground engaging members, wherein the platform is located between the axle and the ground in use.

Preferably the kiteboard comprises two pair of ground engaging members and an axle between the ground engaging members in each pair and/or the ground engaging members comprise wheels.

Preferably an axle is rotateable, or pivotable about a spindle which spindle is inclined at an angle to the ground in use and is preferably substantially straight. The angle is preferably between 15 and 35 degrees and more preferably about 20 degrees. Preferably still the spindle comprises a bolt. Preferably two axles each rotate on separate spindles, the two spindles being inclined in opposite directions at angles to the platform.

Preferably the axle can be removed making the kiteboard capable of travelling across a surface such as water or wet grass with the platform in contact with the surface. More preferably the axle is attached and detached from the kiteboard by fastening an unfastening a bolt and preferably still by only fastening and unfastening a bolt. Preferably the bolt comprises a headed bolt or cap screw and/or the spindle comprises the bolt for attaching and detaching the axle to and from the kiteboard.

Preferably the underside of the platform is substantially planar and free from obstructions.

Preferably the axles are kept parallel with the platform by a leaf spring which leaf spring is preferably attached to the axle.

Preferably the axle is ellipse shaped in cross section.

Preferably the kiteboard comprises carbon and glass fibre and/or is laminated with a carbon/aramid composite.

According to a second aspect of the invention there is provided a kiteboard comprising a platform on which a person stands in use, a pair of ground engaging members and an axle between the pair of ground engaging members, wherein the axle can be removed making the kiteboard capable of travelling across a surface such as water or wet grass with the platform in contact with the surface.

According to a third aspect of the invention there is provided a wheel comprising a rim wherein the rim comprises two axially separable components. Preferably the two components are substantially the same size and/or the two components are connectable by rotation and more preferably the two components are substantially identical

Preferably the two components each comprise a face and a face comprises a connector for connecting to the other face. More preferably both faces comprise a connector for connecting to the other face and/or a connector comprises a bayonet fastener. Preferably still the bayonet fastener comprises a protrusion and recess on each face wherein the protrusion of one face fits into the recess of the other face.

Preferably the rim comprise a stepped upper surface wherein a step is inclined towards the centre of the rim to engage a tyre in use. More preferably the wheel comprising a tyre with a lower surface in contact with the upper surface of the rim wherein the lower surface of the tyre fits into the upper surface of the tyre.

An embodiment of the invention will now be described, by way of example only ,with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a kiteboard according to the invention;

Figure 2 is a plan view of the platform of the kiteboard of Figure 1;

Figure 3 is a side view of the platform of Figure 2;

Figure 4 is a perspective view of the platform of Figure 2

Figure 5 is a perspective view of an axle of the kiteboard of Figure 1;

Figure 6 is a side view of the axle of Figure 4:

Figure 7 is a side view of one end of the kiteboard of Figure 1 without the wheels attached to the axle: Figure 8 is a sectional view of Figure 7;

Figure 9 is a plan view of the kiteboard of Figure 1;

Figure 10 is a diagram showing the position of a person on a kiteboard according to the invention when moving in a straight line, and a kite;

Figure 11 is a diagram showing the orientation of the axles of a kiteboard according to the invention when moving in a straight line.;

Figure 12 is a diagram showing the position of a person steering upwind with a kiteboard according to the invention, and a kite;

Fi ure 13 is a diagram showing the orientation of the axles of a kiteboard according to the invention when steering upwind;

Figure 14 is a front view of the kiteboard of Figure 1 shown without the wheels and with the axles in the positions needed to steer upwind;

Figure 15 is a plan view of the kiteboard of Figure 1 shown without the wheels and with the axles in the positions needed to steer upwind;

Figure 16 is a front view of a wheel according to the invention substantially similar to the wheels shown in Figure 1;

Figure 17 is a perspective view of the wheel of Figure 16;

Figure 18 is a rear view of part of a half of the wheel of Figure 16;

Figure 19 is a sectional view of the top of a tyre for use with the wheel of Figure 16; Figure 20 is a sectional view of the top of a second embodiment of a tyre for use with the wheel of Figure 16; and

Figure 21 is a sectional view of the top of a third embodiment of a tyre attached to the wheel of Figure 16.

Referring to Figure 1 there is shown a kiteboard 10 comprising a platform 12, two axles 14, four wheels 16 and two leaf springs 18 each located between an axle 14 and the platform 12. A user U (not shown in Figure 1) of the kiteboard 10 stands on the platform 10 in a manner similar to a conventional surf or skateboard.

In Figure 2 is shown the platform 12 without the axles 14 and wheels 16. The platform 12 comprises a front end 20 a middle section 22 and an end section 24.

Front section 20 has a curved outer edge 25 and has three projections from its surface: outer support 26 in the centre of the section 20 and two raised elements 28 and 30 for attaching and/or abutting leaf spring 18. End section 24 is substantially the mirror image of front section 20. Middle section 22 comprises substantially straight edges 32 and two inner supports 34 each opposite a corresponding outer support 26 on the end and front sections 24 and 20 respectfully. In use a user U can place his or her feet anywhere on the middle section but typically would place one foot at each end of the middle section adjacent the inner supports 34. Alternatively the platform 12 can be provided with attached bindings to secure the user U to the board.

In Figure 3 it can be seen that the middle section 22 is substantially planar and the front and end sections 20 and 24 curve upwards to apexes 36. The lower surface 38 underneath of the platform 12 is clear of any obstructions forming a smooth substantially planar surface.

The supports 26 and 34 can be seen in more detail in Figure 4. Outer support 26 comprises a three sided base 42 in contact with the upper surface 40, an inner face 44 and a curved, wedge-like, upper surface 46 between the base 42 and face 44. The base 42 is attached to the surface 40. Face 44 comprises two substantially straight sides 48 which with the front side 50 of base 42 approximate a triangle with a rounded apex 52, which face 44 is inclined at an angle to the middle section 22. Curved wedge 46 approximates an ellipsoidal wedge.

Face 44 comprises a hole 54 spaced equally from the two straight sides 48 and proximate the apex 52. A slightly larger aperture 56 is located on the surface of the curved upper surface 46. The aperture 56 and hole 54 form the entrance and exit of a continuous circular bore 58.

Inner support 34 comprises a three sided base 60, an outer face 62 and two substantially straight sides 64 between the base 60 and face 62, the two sides 64 meeting at a rounded apex 66.

Outer face 62 is similar but smaller to inner face 44 and both faces 44 and 62 are inclined at substantially the same angle β with respect to a plane defined by the upper surface 40 of the middle section 22. Equally spaced from the two straight sides 64 and proximate the apex 66 is an aperture 68 leading to a tapped bore 70.

Bore 58 and tapped bore 70 are both substantially straight so that line L travels through the centre of the two bores 58 and 70 which is at an angle α to the surface 40 of the middle section. Angle α in this embodiment is the corresponding angle of β as outer face 62 is perpendicular apex 66. Angle α is preferably between fifteen and thirty five degrees and more preferably about twenty degrees.

Platform 12 is preferably around 1200 to 2000 mm long, 250 to 400 mm wide and 10 to 30 mm thick. The platform 12 preferably comprises a glass fibre and carbon core with an outer, preferably laminated, surface comprising a carbon/aramid composite. The aramid gives the platform 12 good abrasion resistance.

The platform 12 without the wheels 16, axles 14 or springs 18 as shown in Figures 2 to 4 is still suitable for use with a kite. The platform 12 acts like a simple ski or snowboard and can be pulled by a kite over shallow water, wet beaches, wet grass or snow due to the smooth and unobstructed nature of the underneath surface 38. The thickness of the platform is preferably substantially uniform across its entire length as this gives the board most versatility. Alternatively the platform could be thicker in the end and front sections 24 and 20 than the middle section 22 in a similar manner to a conventional snowboard, making it most suitable for snow or be thicker in the middle section 22 then the end and front sections 24 and 20 in a similar manner to a conventional surfboard, making it more suitable for use on water.

In Figure 5 is shown an axle 14 comprising a cylinder 80 central shaft 82 and two wheel bearing rod ends 84, which are all preferably made of stainless steel.

Shaft 82 has an elliptical cross section which is constant through the length of middle section 86 but rotates round through end sections 88 such that the elliptical outer face 90 is off line with the cross section of the middle section 22. This can be clearly seen in Figure 6 where the outline 92 of the middle cross section can be seen to be off axis with and slightly larger than outer face 90. Line 94 represents the top of the shaft 82 and it can be seen to run at angle across the length of end section 88.

Attached to outer faces 90 are the two rod ends 82. These rod ends 82 are of circular cross section and are considerably thinner than the central shaft 82. The two rod ends 84 are in line with each other and are designed to have wheels fitted and rotated about them. Preferably the two wheel bearing rod ends 84 form part of one continuos rod which runs through the entire length of the axle 14.

In the centre of shaft 82 is a cutaway 96 into which is welded cylinder 80. Cylinder 80 has tapered edges 98 and bushing 100 through the centre of the circular cross section throughout the entire length of the cylinder 80. In Figure 6 is shown that the angle between the centre of bushing 100 and the longest diameter of the ellipse of outer face 90 is approximately . The outer cylinder surface 102 is substantially parallel to bushing 100. In Figure 7 can be seen axle 14 attached to the platform 12. Cylinder 80 is inserted between inner face 62 and outer face 44. A bolt 104 (not shown in Figure 7) is inserted through bore 58 and bushing 100 and screwed into tapped bore 70. The bolt 104 acts as a spindle about which axle 14 can rotate or pivot. Distance D determines the amount the axle 14 can rotate before the shaft 82 abuts the platform 12 and prevents further rotation. The axles 14 are provided with bearings and spacers which allow them to rotate freely around the bolts 104.

The longest diameter of elliptical outer face 90 is substantially parallel to the middle section of the platform 12. In use this helps the shaft 82 can cut through air and water when moving.

In Figure 8 is shown the bolt 104 which is preferably a headed bolt or cap screw, and may be fastened by an Allen key for example. In the embodiment shown only the portion of the bolt 104 which engages tapped bore 70 is threaded.

In Figure 9 is a plan view of the completed kiteboard of Figure 1. Each leaf spring 18 comprises ends 106 and may be attached to the platform 12 by its ends 106 being pushed beneath raised elements 28 and 30 or alternatively the leaf spring 18 merely rests on the platform 12 with the ends 106 abutting the raised elements 28 and 30. The leaf spring 18 can rest under the axle 14 or alternatively can be attached to it so that attachment and removal of the axles 14 to the platform 12 is made even easier. With the spring 18 in place the bushing 100 will be lined up with the bores 70 and 58 so that just the bolts 104 need be inserted to complete the kiteboard 10. The leaf springs 18 are preferably fifty to one hundred and fifty mm long, ten to thirty mm wide and three to twelve mm thick.

Wheels 16 are attached to rod ends 84 and can rotate on them allowing the kiteboard 10 to move freely across the ground G. A user U of the kite will stand on the platform 12 in a similar manner to as explained above when the wheels are not attached to the platform.

The kiteboard 10 can be pulled along by a kite such as the ram-air kites or inflatable kites used with surfboards. Nonnally there will be substantially even weight distribution on the kiteboard 10 and it will move in a straight line with the platform 12 horizontal as shown in Figure 10.

Figure 11 shows that when the board is moving in a straight line, the platform 12 is parallel to the ground and a theoretical cone formed from lines L has a pinnacle formed directly underneath the centre of the platform 12. This moving straight position will normally be maintained due to the stability of the platform caused by it being below the axles 14 with a low centre of gravity . The position is also helped to be maintained by the resilience of leaf springs 18 against the axles 14.

When the kite pulls more forcibly on the user U. The user's instinct is then to lean further backwards to counter the pull, and this will place more weight on the far side of the kiteboard 10 from the kite. This cause the platform 12 to rotate about the axles 14 pushing down on the leaf springs 18. This position is shown in Figure 12 and causes the kiteboard 10 to steer upwind keeping the lines to the kite taut.

Because all the wheels 16 must stay in contact with the ground and the axles 14 can pivot on the bolts 104, the rotation of the platform 12 causes the axles 14 to move from being parallel and for the pinnacle of the cone formed by the lines L to move to one side of the centre of the kiteboard 10. With the axles 14 out of parallel the wheels 16 are closer together on one side of the kiteboard 10 and further apart on the other side as shown in Figures 12 to 14.

Referring to Figure 13 the wheels 16 form two circular arcs c and d of different radii but with the same centre. These effectively form the turning circle and in the embodiment shown the turning circle will be approximately 5.5m in radius with the axles 14 rotated to their full amount. The turning circle is much larger than on known skateboards and mountainboards which is beneficial for kiteboarding. Sudden sharp turns can pull hard against the taut kite lines pulling the user U of the board (or the user and board over into one side if the user is strapped in bindings) or cause the lines to slacken too rapidly causing loss of control of the kite. The size of the turning circle is determined by the angle α and the distance between the axles 14 which is preferably much larger than a skateboard or mountainboard.

The movement of the axles 14 relative to the platform 12 when steering are shown in Figures 14 and 15 which for illustrative purposes are shown without the wheels 16. Whilst the platform tilted to the ground G the axle 14 must stay parallel to the ground. as the wheels 16 at each end abut the ground and can not move downwards. Since the axles 14 are pivoted at angle α to the platform in opposite directions, the axles move out of parallel with each other as shown in Figure 15.

The wheels 16 are preferably much larger than on a skateboard and most preferably between two hundred and sixty to three hundred and forty mm in diameter. This allows the platform to be placed below the axles 14 which gives increased stability to the kiteboard 10 and lowers the centre of gravity of the kiteboard 10, and of the user U when standing on the platform 12. Because the platform 12 is below the axles 14 the user U is not a passenger rolling down a hill instead he is transferring the power of the kite to the kiteboard 10 and therefore is always driving the board forward.

The axles 14 are also preferably long so that the wheels 16 are far apart. This lessens the likelihood of the kiteboard being turned over or onto its side which can be a desirable feature for skateboards allowing tricks to be done but is not desirable for kiteboarding where a kite is constantly pulling the user to one side. Most preferably the central shaft 82 of the axle 14 is between two hundred and seventy five and five hundred mm long separating the wheels 16 by approximately the same distance. The wheels 16 are preferably between one hundred and one hundred and eighty mm wide.

Because the kiteboard 10 is suspended so far below its pivot points (the bolts 104) and it needs positive pressure to tilt the deck it provides a very stable platform such that the invention can be made without any springs 18 and merely rely on its natural stability. A wheel 16 according to the invention is shown in Figure 16 and comprises a hub 110 three spokes 112, a rim 114 and a tyre 116. The hub 110 comprises a central aperture 1 18 through which rod 84 is positioned in use. The diameter of aperture 118 is preferably just larger than the diameter of rod end 84 so allowing the wheel 16 to turn freely about the axle 14 without being too loose. Each spoke 112 comprises an aperture 120 preferably closer to the tyre 116 than the hub 110.

hi one embodiment the wheels can be solid and formed substantially in one piece, while in a preferred embodiment the wheel 16 is axially split into two halves 122 and 124 as shown in Figure 17. The halves 122 and 124 join together at interface 126. The two halves 122 and 124 are preferably substantially identical, each comprising half of the hub 1 10, spokes 122 and rim 114.

Interface 126 comprises the adjoining inner wheel faces 128 of each half 122 and 124. Each wheel face 128 comprises a series of bayonet fasteners 130 located in the rim 114. There are preferably between three and nine, more preferably a multiple of three and most preferably six of the bayonet fasteners 130.

One of the bayonet fasteners 130 is shown in Figure 18. The bayonet fastener 130 comprises a bayonet clip 132 which protrudes from the wheel face 128 and a bayonet socket 134 which extends into the wheel face 134. Bayonet clip 132 comprises a curved sloping section 136 which begins at position 137 level with the rest of the wheel face 128 and curves away from the wheel face through curved section 136 to a straight section 138 substantially parallel with the rest of the wheel face 128 and ends at a clip abutment 140 substantially perpendicular to the rest of the wheel face 128. Bayonet socket 134 has a substantially identical profile to clip 132 but curves inwardly and instead of ending at clip abutment 140 has a straight channel (not shown) extending beneath the clip 132 and ending at a socket abutment (not shown) directly below the start position 137 of clip 132 or at a position even further from clip abutment 140. To form the complete wheel 16, the two halves 122 and 124 must be attached together. This is done by placing the bayonet clips 132 of one half 122 or 124 into the sockets of the other half 124 or 122 and rotating one half relative to the other such that the bayonet clips 132 slide into the straight channels until clip abutments 140 abut the socket abutments. This fixes the wheels together axially but to stop any rotational movement and to reduce stress on the bayonet fasteners 130 fasteners, such as nuts and bolts, are preferably inserted through apertures 120 and used to secure the halves 122 and 124 in place.

As the kiteboard 10 is suitable for use on a variety of surfaces it is beneficial to use a range of different tyres 116 suitable for different surfaces. A first embodiment of tyre 216 is shown in Figure 19. The tyre comprises a lower surface 218 and an upper surface 220. The upper surface 220 is substantially flat making it suitable for use on grass for example.

Lower surface 218 has a first level 222, a second level 224 and a third level 226 each progressively further from upper surface 220. Each level is joined to the next level via a step 228. The step 228 circled in Figure 19 comprises a slanted portion 230 which connects level 222 with level 224. As can be seen, the two levels 222 and 224 overlap across the width of the tyre 220 and hence the slanted portion 2030 cuts backwards from an end of level 228 to the nearest end of level 222. The other steps 228 are substantially similar to the one circled.

In Figure 20 is shown a second embodiment of tyre 316 comprising a lower surface 318 and an upper surface 320. Lower surface 318 is substantially the same as lower portion

218. Upper surface 320 curves towards an apex 332 and comprises four ribs 334. The ribs 334 make the tyre 316 particularly suitable for use on sand and other soft terrain.

Various different numbers and shapes of ribs can be used but the embodiment shown lias five ribs 334 with two ribs 334a on the extreme ends of the tyre 316, one rib 334c in the centre and two ribs 334b in between the others. Each rib 334 is substantially triangular in shape with the base 336 nearest to the lower surface 318 and the point 338 projecting outwards. Figure 21 shows a third embodiment of tyre 416 attached to the wheel rim 114 to form a complete wheel 16. The upper surface of tyre 416 curves to an apex 432 and the lower surface 418 is substantially identical to lower surfaces 218 and 318.

The wheel rim 114 has an upper surface 434 with a profile which matches that of the tyre lower surface 418. Tyre 316 is fixed onto the rim 114 as teeth 436 abut slanted sections 430 and prevent the tyre 316 from being forced upwards relative to the rim 114.

As with the rest of the wheel 16 the rim 114 is formed by the two halves 122 and 124 meeting at interface 126. The tyre 416 is attached by being placed on top of one or both of the halves 122 and 124 prior to their attachment and with them axially spaces. The levels of the tyre 416 should be adjacent their corresponding levels 436 on upper surface 434 so that when the two halves 122 and 124 are attached to each other the tyre 436 will be fixed in the position shown in Figure 21.

Since the lower surfaces 218, 318 and 418 are substantially identical they will each match the rim upper surface 434 allowing any of the tyres 216, 316 or 416 to be attached to the wheel 16 in a similar manner. Any tyre made with a matching lower surface can thus be quickly attached, removed, or replaced onto a wheel 16. It is possible to change between different tyres leaving the half 122 or 124 nearest the platform 12 in use, on the axle 14 when changing tyres 114.

Kiteboard 10 is suitable to be used for any traction sport and in addition to being pulled by a kite could be pulled by a motor boat, jet ski or land vehicle.

Claims

1. A kiteboard comprising a platform on which a person stands in use, a pair of ground engaging members and an axle between the pair of ground engaging members, wherein the platform is located between the axle and the ground in use.

2. A kiteboard according to claim 1 which comprises two pairs of ground engaging members and an axle between the ground engaging members in each pair.

3 A kiteboard according to claim 1 or 2 wherein the ground engaging members comprise wheels.

4. A kiteboard according to any preceding claim in which an axle is rotatable, or pivotable about a spindle which spindle is inclined at an angle to the ground in use.

5. A kiteboard according to claim 4 in which the angle is between 15 and 35 degrees and preferably about 20 degrees.

6. A kiteboard according to claim 4 or 5 in which two axles each rotate on separate spindles, the two spindles being inclined in opposite directions at angles to the platform.

7. A kiteboard according to claim 4, 5 or 6 in which the spindle is substantially straight.

8. A kiteboard according to claim 4, 5, 6 or 7 in which the spindle comprises a bolt.

9. A kiteboard according to any previous claim in which the axle can be removed making the kiteboard capable of travelling across a surface such as water or wet grass with the platform in contact with the surface.

10. A kiteboard according to claim 9 in which the axle is attached and detached from the Idteboard by fastening an unfastening a bolt.

1 1 . A kiteboard according to claim 9 or 10 in which the axle is only attached and detached from the kiteboard by fastening and unfastening a bolt.

12. A kiteboard according to claim 9, 10 or 11 in which the bolt comprises a headed bolt or cap screw.

13 A kiteboard according to any of claims 9 t ol2 when dependent on claim 4 wherein the spindle comprises the bolt.

14. A kiteboard according to any previous claim wherein the underside of the platform is substantially planar and free from obstructions.

15. A kiteboard according to any preceding claim in which the axles are kept parallel with the platform by a leaf spring.

16. A kiteboard according to claim 15 wherein the leaf spring is attached to the axle.

17. A kiteboard according to any preceding claim wherein the axle is ellipse shaped in cross section.

18. A Idteboard according to any preceding claim comprising carbon and glass fibre.

19. A kiteboard according to any preceding claim which is laminated with a carbon/aramid composite.

20. A Idteboard comprising a platform on which a person stands in use, a pair of ground engaging members and an axle between the pair of ground engaging members, wherein the axle can be removed making the kiteboard capable of travelling across a surface such as water or wet grass with the platform in contact with the surface.

21. A wheel comprising a rim wherein the rim comprises two axially separable components.

22. A wheel according to claim 21 wherein the two components are substantially the same size.

23. A wheel according to claim 21 or 22 wherein the two components are substantially identical

24 , A wheel according to claim 21, 22 or 23 wherein the two components are connectable by rotation

25. A wheel according to any of claims 21 to 24 wherein the two components each comprise a face and a face comprises a comiector for connecting to the other face.

26. A wheel according to claim 25 wherein both faces comprise a connector for connecting to the other face.

27. A wheel according to claim 25 or 26 wherein a connector comprises a bayonet

Fastener.

28. A wheel according to claim 27 wherein the bayonet fastener comprises a protrusion and recess on each face wherein the protrusion of one face fits into the recess of the other face.

29. A wheel according to any of claims 21 to 28 wherein the rim comprise a stepped upper surface wherein a step is inclined towards the centre of the rim to engage a tyre in use.

0. A wheel according to claim 29 comprising a tyre with a lower surface in contact with the upper surface of the rim wherein the lower surface of the tyre fits into the upper surface of the tyre.