BACKGROUND OF THE INVENTION Bicycles and motorcycles typically employ fork suspensions comprising a pair of telescoping assemblies between which the front wheel is mounted on a hub and axle that have essentially equal diameters on each side, connected to each leg of the fork. Each telescoping assembly has telescoping inner and outer tubes. A shock cushioning device is generally provided between the tubes, often including a spring and hydraulic damper.

Generally, the outer tubes are connected at lower ends thereof to an axle of the front wheel, and the upper ends of the inner tubes are connected to a steer tube that is mounted within a head tube of the vehicle frame. The suspensions absorb shocks that are encountered during operation of the vehicle over uneven terrain, improving handling at higher speeds and concomitantly providing a more comfortable ride under rough conditions.

Many suspension designs incorporate bushings between the outer and inner tubes to guide the movement of the tubes with respect to each other and to reduce friction therebetween. The bushings at the ends of both tubes, however, suffer from undesirable static friction called"stiction", which is a term well-known in the art, referring to friction caused by compressing the bushings against the bearing surface that they abut when the tubes are substantially motionless with respect to each other, which hinders the commencement of the sliding of the bushings against the bearing surface. Bending moments between the inner and outer tubes cause the tubes to press tightly against the bushings, increasing stiction, which prevents the tubes from smoothly telescoping. As a result, a high initial force is required to overcome the stiction. This worsens handling and comfort. Because of stiction, the suspension systems using such bushings tend to stick and then suddenly release or move, and the point at which movement starts becomes higher with higher loads, such as when radial loads are increased due to braking.

To overcome the stiction problems of conventional bushings, other bearing systems have been developed. U. S. Patent No. 2,493,342 discloses an anti-friction reciprocating-type bearing for use in aircraft offset landing gear. The aircraft landing-gear strut has reciprocating ball bearings disposed between a cylinder piston and an outer cylinder, around the circumference thereof. The ball bearings allow the inner cylinder to move telescopically with respect to the outer cylinder. As the balls are cylindrical, swiveling of the cylinder piston with respect to the outer cylinder is also permitted. The patent mentions that a shimmy damper, which is external to the cylinders, may be used to restrict the swiveling. In addition, the ball bearings operate on point-contact with each cylinder, creating high stresses where the contact is made between the balls and the cylinders, speeding wear.

Particularly in suspensions with telescoping assemblies, it is desirable to space the bearings to stations distant from each other to best maintain the alignment of the telescoping members and reduce radial loads on the bearings. Although needle bearings placed between the telescoping members prevent axial rotation of the members and spreads compression loads over a greater are in each bearing, as the members telescope with respect to each other, the bearings roll along the length of the members, requiring that the bearings be placed a distance that is less than the distance between the telescoping ends of the members.

It is desirable to provide a vehicle suspension with bearings that can bear a combination of high radial loads occasioned by braking and bumps, while at the same time providing smooth, stable and tight motion between relatively moving vehicle supports. It is further desirable to provide a vehicle suspension with significantly reduced stiction with bearings that can be placed and maintained near the ends of the supports.

SUMMARY OF THE INVENTION The invention is directed to a vehicle suspension that has two supports associated for telescopic movement. A recirculating non-spherical roller bearing assembly is attached to one of the supports, abutting a race on the other of the supports. The shape of the bearings and of the race control, and preferably prevent, axial relative rotation between the supports.

The preferred embodiment is a steerable fork with three recirculating roller bearing assemblies fixed to the end of one of the supports, rolling against three corresponding races on the other of the supports. The end of the other support has a second bearing, which may comprise additional recirculating roller-bearing assemblies or a bushing. A wheel is mountable to a fork leg laterally below the top attachment of the fork, which is attachable to the bicycle frame.

As a result of this construction, stiction is significantly reduced, and rotational and torsional loads are borne internally to the suspension by the recirculating bearings. Additionally, the recirculating bearings are retained at the end of the support or supports to which they are attached, instead of rolling towards and away from the end as nonrecirculating bearings tend to do during telescopic movement of the supports. This placement reduces the compressive loads imposed on bearings that are placed axially closer together. This arrangement is particularly useful in single-sided suspension forks, in which bending moments are particularly high in the single fork leg, which must additionally support the entire weight that is placed on the wheel to which the fork is attached.

A coupling is also provided to house the bearing assemblies. The coupling is preferably detachably mountable to the end of one of the supports to facilitate replacement of the bearing assemblies.

The preferred fork has an axle attached to a fork leg. The axle is tapered axially to increase the strength thereof, while reducing weight. The axle preferably has a larger diameter portion adjacent the leg, and a small diameter portion remote from the leg.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an embodiment of a suspension constructed according to the present invention; FIG. 2 is a cut-away, exploded view of a portion of the suspension system of FIG. 1; FIG. 3 is a perspective view of another embodiment of the suspension;.

FIG. 4 is a cut-away front view of another embodiment of the suspension; FIG. 5 is a cross-sectional view of a bearing assembly constructed according to the invention;

FIG 6 is a perspective view of another embodiment of the suspension; FIG. 7 is a cross-sectional end view of the bearing assembly of FIG. 6; FIG. 8 is a side view of a the bearing assembly; FIG. 9 is a cutaway front view of the bearing assembly; FIG. 10 is a perspective view of a coupling constructed according to the invention; FIG. 11 is a cross-sectional side view thereof; FIG. 12 is a perspective view of another embodiment of the invention; FIG. 13 is a cross-sectional side view of the telescoping tubes thereof; FIG. 14 is a left side view of a hub of a single-sided fork; FIG. 15 is a front cross-sectional view thereof; FIG. 16 is a right side view thereof with the fork leg removed; FIGS. 17 and 18 are cross-sectional views other embodiments hubs of single- sided forks; FIGS. 19,19A, and 20 are cross-sectional views of alternative embodiments of cantilevered ends of single-sided fork hubs; FIG. 21 is a perspective view of a fork leg with a tapered axle, cast as a single piece; FIG. 22 is a front view of a dropout on a single sided fork; FIG. 23 is a cross-sectional front view of an alternative axle attached to a fork leg; FIGs. 24 and 25 are a perspective and a cross-sectional side view of an single-sided fork with a dropout that has an offset axle; FIG. 26 is a perspective view of another embodiment of a single sided fork; FIG. 27 is a cross-sectional view of an alternative embodiment of a single- sided fork leg; FIGs. 28 and 29 are a front view and side view of a needle bearing cage of the fork of FIG. 27; and FIG. 30 is a cutaway cross-sectional view of the cantilevered end of another embodiment of the axle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, bicycle frame 10 has a head tube 11. A suspension includes fork 12, which has an attachment attachable to the bicycle frame, which is preferably an inner steer tube 13 which extends upwardly through the head tube 11 into an upper outer steer tube 14. The tubes 13,14 are supports of the suspension. The front fork 12 is coupled to the front wheel between fork legs 12a and handle bars that are connected to handlebar stem 15. The upper end of the outer steer tube 14 is connected to the handlebar stem 15. Upper and lower bearings 16 and 17 can be provided to journal the steer tubes 13,14 within the head tube 11 for steering rotation. The assembly of the steer tubes 13 and 14 is connected together and retained within the head tube 11, and a suitable shock absorber and spring system is preferably mounted within the tubes 13,14.

The outer wall 20 of the inner steer tube 13 has a plurality of axially extending longitudinal bearing surfaces or races, which in this embodiment are flats 23.

Preferably three such flats 23 are provided, although a different number can be used. The inner wall 28 of the outer tube 14 has a set of opposing flats 32. These flats on both tubes 13,14 extend in the axial direction of the tubes. The tubes 13,14 are preferably formed of steel and can be formed from Nitriloy or equivalent, and the flats 23 are preferably hardened through the use of copper masking techniques as used in the automotive industry.

A bearing assembly 24 is fixed to one of the tubes 13,14, preferably to the outer tube 14. The bearing assembly 24 is comprised of three sets of recirculating roller bearings 36, preferably needle bearings, which have a length of preferably at least four times their diameter to significantly resist axial relative rotation of the tubes 13,14. More preferably, the length of the bearings 36 is more than 7 times the outer diameter. The bearing assembly 24 additionally has cages 42 attached to the lower end 37 of the outer tube 14. The bearings 36 are disposed between the respective flats 23,32 of the inner and outer tubes 13,14, as diagrammatically shown in FIG. 2. The recirculating needle bearings 36 are disposed normal to the axial direction of the tubes 13,14.

The recirculating needle bearings 36 allow the inner tube 13 to freely telescope with respect to the outer tube 14 along a predetermined telescoping path.

Additionally, the non-spherical, recirculating needle-bearings 36, in conjunction with the

associated flats 23 of the inner tube 13, prevent relative twisting between the inner and outer tubes 13,14 about the an axis parallel to the telescoping path, and thus transmit steering torsional or rotary action from handlebar stem 15 via the telescoping tubes 13,14 of the fork 12 to the front wheel. The flats 23 and recirculating needle bearings 36 carry a combination of loads including very high radial loads from the fork 12 during movement over rough terrain and during braking and the like, while stabilizing a rotational and torsional connection from the handlebars to the fork 12. No external coupling or linkage is needed to enable transmission of the rotational and torsional forces for steering, and the present suspension assembly can be made sufficiently strong, light and compact such that a single telescoping assembly can be provided for a bicycle fork without requiring a pair of telescoping assemblies. Sufficient longitudinal or axial telescoping travel can be provided, such as over several centimeters. The length of the flats 23 establishes the extent of telescoping action of the tubes 13,14. This assembly absorbs bumps, facilitates handling of the bicycle, is more controllable over rough conditions, and provides a tight positive steering action.

Similarly to bearing assembly 24, recirculating bearing assembly 25 includes three groups of recirculating needle bearings 37, reciprocably mounted in bearing cages 41, which are fixed to the upper end 38 of the inner tube 13. Needle bearings 37 abut the bearing surfaces 32 of the outer tube 14 to reduce friction therebetween and to transmit axial rotation therebetween.

The interior 39 of the inner tube 13 is hollow to reduce the weight of the suspension fork and to provide space for a shock absorber. Preferably a shock absorber is disposed within the inner and outer tubes 13 and 14 as disclosed in U. S. Patent No.

5,320,374, which is hereby incorporated by reference. A spring is also preferably provided between tubes 13,14.

A second embodiment of a suspension fork 9 constructed according to the present invention is shown in FIG. 3. This system is particularly useful for downhill bicycles and motorcycles. The suspension 9 is comprised of an outer support tube 14 that is secured to a steering tube 18, which is attached to handlebars 18a. The steering tube 18 is rotatably secured to a bicycle or motorcycle frame. A top bracket 7 and a bottom bracket 8 are used to secure the outer tube 14 to the steering tube 18. Recirculating needle bearing

assemblies 24 are secured to the lower end of the outer tubes 14 and rollingly abut flats 23 of the inner tubes 13. Inner tubes 13 are mounted to wheel 19 at attachment points, which are preferably axle brackets 5 that receive the front hub 19a of wheel 19. Increased telescoping travel can be provided between tubes 13,14 of this embodiment of over ten centimeters.

Another embodiment of the suspension system is shown in FIG. 4. This embodiment is comprised of a single outer tube 14 secured to a steering tube 18 via a top bracket 7 and a bottom bracket 8. Inner tube 13 is attachable to a wheel through axle 6.

Inner tube 13 is telescopically received in outer tube 14. Recirculating needle-bearing assembly 24 is fixed to the lower end of the outer tube 14, with needle bearings abutting the outwardly facing bearing surface 23 of the inner tube 13. Also, recirculating needle-bearing assembly 25 is fixed to the upper end of the inner tube 13, with recirculating needle bearings abutting the inwardly facing bearing surface 32 of the outer tube. Dial 90 is connected to a shock absorber within the inner and outer tubes to vary the damping rate thereof.

FIG. 5 illustrates the bearing cage 42 that houses the recirculating needle bearings 36 between a flared or locally widened base 79 of an outer tube and the flats 23 of the inner tube 13. The bearing assembly 25 fixed to the upper end of the inner tube 13 is similar to the bearing assembly 24 shown in these figures. The cage 42 has a continuous track 60 with a raceway that includes a feed raceway 61 disposed parallel to a contact raceway 62, which are continuous and interconnected at their ends by two arcuate supply raceways 63 for allowing the bearings to circulate around track 60. The bearings protrude by a distance 64 from the open base 65 of the cage 42, abutting the bearing surface 23 of the inner tube 13. Although raceways 61 and 62 are linear and parallel, in an alternative embodiment the raceways are nonparallel and arcuate. Similarly, the raceways may be formed to receive tapered roller bearings.

The cage 42 abuts the inner wall 78 of outer tube 79. Although the lower ends of the cage 42 and of the outer tube 79 are shown flush with one another, the cage 42 may be contained completely within the boundaries of the outer tube 79, and a protective cover may be placed thereover. Fasteners 71, such as screws or press fit pins, secure the

cage 42 to the outer tube 79. A shim 71 fitted between the cage 42 and the outer tube 79 applies a preload to the roller bearings 36 against the bearing surface 23.

Referring to fork suspension fork 100, shown in FIG. 6, two outer tubes 102 telescopically receive two inner tubes 104. The outer tubes 102 are attached via brackets 105 together and to a steer tube 107. The outer tubes 102 also have flared lower ends 106 for housing bearing assemblies of recirculating roller bearings. Referring to FIG. 7, the flared ends 106 include three recessed areas 108 for attaching the recirculating bearing assemblies 110. Referring to FIGS. 7-9, the bearing assemblies 110 include a cage 111 with a base plate 112 with an inner race 113 that has front and back surfaces 114,116 and curved end surfaces 118. A mounting wing 120 extends laterally to each side of the inner race 113.

Fasteners 122 are inserted through holes 124 of the mounting wings 120 and secure the base plate 112 to the flared end 106 of the outer tube 102.

Retaining plates 126 are mounted to the base plate 112 by receiving the mounting wings 120 through openings 128 in the retaining plates, preferably resulting in a press fit association. The retaining plate 126 on the right side of FIG. 9 is not shown to better display the detail of the base plate 112. Where the mounting wings meet the inner race 113 are notches 130 to locate and retain the retaining plates 126. In an alternative embodiment, the retaining plates are welded to the base plate or fixed thereto with fasteners.

The outer edges 138,139 of the retaining plates 126 are bent inwardly, forming outer races 140, which face the inner race 113 across channel 142.

Needle bearings 132 have a roller portion 134 and concentric spindles 136 of smaller diameter than the roller portion 134. The spindles 136 are captured within the channel 142, between the inner and outer races 113,140, thus guiding the needle bearings along a recirculating path around the baseplate 112. The retaining plates 126 extend further from the base plate 112 on the back side thereof than on the front side. To achieve this, the front side of the front outer edges 139 of the retaining plates 126 are thinner than the back outer edges 138. The height of the retaining plates behind the inner race is greater than the diameter of the roller portions 134 of the needle bearings, and is selected to protrude further from the baseplate 112 than the needle bearings 132. On the other hand, the height in front of the inner race 113 of the retaining plates 126 is smaller than the diameter of the roller portions 134 of the needle bearings 132, such that the roller portions 134 thereof protrude

ahead of the retaining plates 126 to contact race 144 of the inner tube 104, so that the needle bearings are compresses between the race 144 and the front race 114 of the baseplate 112.

The retaining plates 126 and the needle bearings 132 fit within a secondary recess 148 within the wall of the flared end 106. Thus, recesses 108 and 148 together form a double recessed area 149.

The inner tube 104 is hollow and has three preferably flattened races 144.

As the inner tube 104 telescopes within the outer tube 102, the recirculating roller bearings roll against the races 144, reducing friction and maintaining the tubes 102,104 in a preferably fixed rotational association. The races 144 and bearing assemblies 110 are preferably disposed about the axis of the tubes 102,104 such that any angle extending through points normal to all of the races is greater than 180 ° so the bearing assemblies 110 by themselves are sufficient to withstand radial loads in any direction.

FIGS. 10 and 11 show a coupling 150 with the general shape of the flared end 106 shown in FIG. 7. The coupling 150 defines the double recessed areas 149 and holes 152 for receiving fasteners that attach to bearing cages 111. The coupling 150 has a ledge 154 extending inwardly adjacent a tube attachment portion 156. Outer telescoping tube 158 is detachably secured within the tube attachment portion 156, and is preferably fixed thereto with fasteners. The coupling 150 can be removed from the outer tube 102 as a unit to facilitate replacement of the bearing assemblies 110. Alternatively the outer tube 158 may be permanently fixed to the coupling 150 be welding or gluing. A seal seat 160 is disposed adjacent the bearing mounting portion 162 of the coupling for placement of a seal to protect the bearing assemblies housed in the coupling 150. In an alternative embodiment, a coupling housing the recirculating bearing assemblies is attachable to the inner tube such that the bearings can abut races in the interior of the outer tube.

FIGS. 12 and 13 show another embodiment of a single-sided fork suspension 164, with a steer tube 166 connected via brackets 168 to an outer tube 170. Inner and outer telescoping tubes 170,172 of fork leg 173 are offset laterally from the steer tube 166, which preferably has a steering axis 171 that extends through the wheel. Thus, the wheel is disposed laterally below the steer tube 166.

A bushing 175 is attached to the upper end of the inner tube 172, extending radially outwardly to abut the inner surface of the outer tube 170 for reducing friction

therebetween. The bushing 175 is preferably self-lubricating and is a grooved sheet wrapped and bonded around the top end of the inner tube 172.

Employing recirculating bearings according to the invention is particularly advantageous in a single-sided fork because the off-center loading of the inner and outer tubes produces increased compression of the bearings against the bearing surfaces of the tubes. Because the bearings are recirculating, they can be localized and maintained as far apart as possible, i. e. at the ends of the tube to which they are attached. Also, since the bearings are nonspherical and cooperate with the bearing surfaces against which they bear to resist relative rotation between the tubes, no additional sliding structure is necessary which could be easily worn due to the increased bending moments in the tubes.

A shock absorbing cartridge 174 is preferably disposed within the inner and outer tubes 172,170 for damping the telescoping movement thereof. The cartridge 174 has a housing 176 containing hydraulic damping fluid and preferably screwed to the top of the inner tube 172. A piston shaft 178 fastened to the top of the outer tube 170 extends completely through the cartridge housing 176 and is coupled to a piston 180, which forces hydraulic fluid between at least two compartments in the cartridge housing 176 through a small orifice for damping movement of the piston 180. The damping rate can be controlled by turning knob 182 located outside of the outer tube 170, at the top end thereof, which alters the size of the opening through which the hydraulic fluid is forced to pass.

Alternatively, the damping rate can be controlled electronically. A second piston 184 at the bottom of the shaft 178 compresses elastomeric and coil springs 186,188 to cushion shocks to the telescoping tubes 170,172 and to extend the compressed tubes 170,172 to a preselected stabilized position.

At the lower end of the inner tube 172 of the single fork leg is a hub 190, which is shown in detail in FIG. 14-16. An axle 192 with outer threads 194 on a leg-side portion 195 is screwed into threaded bore 196 of the fork leg 173 such that the axle 192 cantilevered from the leg 173, in an orientation substantially perpendicular thereto. A retention flange 198 extends radially from the a leg-side end of the axle to prevent the axle 192 from being screwed into the leg 173 beyond a preselected position.

The leg-side portion 195 is preferably generally cylindrical. A hub-side portion 200 of the axle preferably has a generally tapered portion 203, which is preferably

conical, to reduce the weight of the axle while increasing its bending stiffness and strength by increasing the area moment of inertia of the axle 192 since the axle 192 is effectively an cantilevered beam. Thus, the diameter 201 of the axle preferably decreases in a direction away from the leg 173. Cantilevered end 202 of the axle 192, which is disposed remotely from the leg 173, has a smaller diameter portion 204 disposed nearer the leg 173. The tapered portion 203 has an axial length that is preferably more than 50%, more preferably more than 70%, more and most preferably more than about 80%, the length of the axle 192 that protrudes from the fork leg 173 or of the distance between the fork leg 173 and the bearing 210 located furthest from the leg 173.

On opposite sides of the tapered portion 203 are bearing seat portions 206,208, which are preferably cylindrical. Bearings 210,212 are mounted on seats 206,208.

As a result of the taper, bearing seat 206 has a smaller diameter than bearing seat 208, and bearing 210 has similarly smaller inner and outer diameters than bearing 212. End piece 214 is screwed into the hub-side portion 200 of the axle 192 with threads 216. The end piece 214 has a socket 218 to receive a tool to screw and unscrew the end piece 214.

Preferably the socket 218 has a hexagonal cross-section, as shown in FIG. 16. The end piece 214 has a radially extending bearing-retention flange 220 that has a diameter greater than the cantilevered end 202 of the axle and that bears against bearing 210 to retain bearing 210 on the axle 192 against step 222 on the outside of the axle 192.

A hub shell 224, has a preferably cylindrical outer surface 226 with flanges 228,230 extending radially on opposite sides thereof. The flanges have a plurality of spoke holes 232, preferably between about 10 and 25, and most preferably between 16 and 18.

The spoke holes 232 are configured to receive spokes 234 which are connected to the wheel to support the axle, the fork, and the bike frame. The spoke holes 234 of flange 228 are disposed around axis 236 of the axle 192 at a smaller distance than the spoke holes 234 of flange 230. The diameter of the circle extending through spoke holes 234 of flange 228 preferably is about 1.8 inches, and the diameter of the circle extending through spoke holes 234 of flange 230 is preferably about 2.2 inches for a bicycle.

A rotor bracket 238 is disposed adjacent the fork leg 173 and is configured for mounting a disk brake rotor 240 thereagainst. The rotor 240 is attached to the rotor bracket 238 preferably by four bolts 242, but may be attached in other manners known in

the art. Brake calipers 244 are mounted to the fork leg 173 and receive the rotor 240. The callipers are operable by the bicycle rider, preferably via levers mounted on the handlebar, to clamp against the rotor 240 to brake the rotation of the wheel and slow the vehicle. Seal 246 is disposed between bearing 212 and the rotor 244 to seal the bearing 212 and the interior of the hub shell 224.

In the above embodiments, the bearing cages and associated bearing surfaces are disposed at even angular intervals about the telescoping axis of the tubes. Other angular dispositions are also suitable for certain applications. Also, a number of bearing races other than three may be used, and a combination of recirculating roller-bearings and bushings or other bearing types may be employed at a station on the tubes. Additionally, the bearing surfaces or races on the tubes may be of a shape other than flat, but it is preferred that this shape cooperates with the shape of the roller-bearings to control relative axial rotation between the two tubes.

Referring to FIG. 17, axle 248 is press fit, welded, or bonded to the fork leg 173, and the exterior of the leg-side portion 250 preferably is not threaded. Additionally, end piece 252 has a quick release mechanism 254 which is preferably operable by rotating lever 256 of the quick release 254. The quick release 254 fixes the end piece 252 to the axle 248 when the lever 256 is in the locked position shown, and releases the end piece 252 from the axle 148 when the lever is rotated to an unlocked position 258 shown in phantom lines.

Removal of the end piece 252 permits the hub shell 224 with the attached wheel to be removed from the axle 148 for servicing, replacement, or storage.

Referring to FIG. 18, fork leg 290 has a bore 292 that extends only partially therethrough. Thus, the leg has an outer wall 293. Axle 294 has a back wall 296 with a threaded screw sleeve 298. Screw 300 is received through a hole in the back wall and is engaged to the sleeve 298 to capture the axle 294 axially within the bore 292. An alternative embodiment has a plurality of screws or other fasteners fixing the axle to the leg.

Referring to FIG. 19, hub shell 260 has an extension 262 with a recess 263 in which is received a retaining ring 264. The retaining ring 264 is preferably a resilient C- clip which is naturally biased outwardly into the recess 263. The retaining ring 264 abuts end piece 266 to retain the end piece 266 within the open end of the axle 261. An annular seal 268 is disposed between the end piece 266 and bearing 210 to seal the bearing 210 and

the interior of the hub shell 268, protecting against foreign matter such as dirt which can harm the bearings. The end piece 266 also has a step 270 that extends towards the axle 261 and abuts inner race 267 of the bearing 210 to prevent axial movement of the bearing 210 off the axle 261. The retaining ring 264 thus restricts movement of the hub shell 260 past a predetermined position towards the fork leg 173. The end piece 266 can be free rotationally, but captured axially by the retention ring 264. The hub shell 260 includes an inwardly extending step 272 that abuts outer race 269 of the bearing 210, preventing axial movement of the hub shell 260 off of the axle 161. Rotatable bearings 271 ride between the races 267,269 to reduce rotational friction between the hub shell 260 and the axle 261.

Rotational bearing are preferably ball bearings but may alternatively have other suitable shapes such as cylindrical or conical. Alternatively, a retaining ring 273 may be threaded to the inside of the end of the hub shell 275, and may be placed against the outer race 269of bearing 210, as shown in FIG. 19A to retain the bearing therein.

Referring to FIG. 20, axle 274 is shorter than the previous embodiments discussed and has a cantilevered end 276 which axially abuts the inner race of bearing 278.

End piece 280 extends into the axle 274 and is screwed thereto with threads 282. The end piece is configured and has sufficient strength and rigidity to support bearing 278, which is seated on bearing seat 284 of the end piece 280.

The tapered axle described above has increased strength and stiffness due to the tapered shape. The axle is preferably made of titanium and the end piece and hub shell are preferably aluminum alloys. Other materials may alternatively be employed in these parts, such as steels, aluminum, titanium, or composites. FIG. 21, for instance, shows fork leg 286 with axle 288 of unitary construction therewith, preferably formed from a single piece of material. Leg 286 and axle 288 are preferably molded or cast as a single piece.

A separate dropout can also be used to connect the axle to the fork leg. FIG.

22 shows an embodiment of an axle 302 which is unitarily constructed of a single piece with dropout 304. The dropout 304 receives the fork leg 306 and is fixed thereto, preferably by press fitting, but fixation methods also include the use of fasteners, adhesives, welding, and screwing. The axis of the axle 302 is oriented at about a right angle to the axis of the dropout 304.

Axle 308 of FIG. 23 has a collar 310 extending radially therefrom to limit its insertion in dropout 311. A nut 312 is threaded to the threaded back portion 314 of axle 308, to secure the axle 308 in a transverse bore in the dropout 311, which has a vertical bore 316 configured to receive the fork leg coaxially.

FIG. 24 shows an alternative embodiment of a single sided fork with dropout 318, preferably made from impact extruded aluminum tube, fixed to the end of the lower, inner tube 320 of the telescoping for leg 322. The dropout has an axle mounting portion 324 that is offset forward of the axis of the leg 322. The axle 326 is thus also offset forward of the leg 322. Thus allows access to the bottom end 328 of the tube322 and dropout 318, through which a damper adjustment rod 330 may extend, as shown in FIG.

25. Adjustment rod 330 is preferably coaxially rotatably mounted within shaft 332 of shock absorber 334. The adjustment rod is preferably rotatable by knob 336 at the bottom end of the dropout 318 to vary the size of at least one orifice communicating top and bottom chambers of housing 338 of the shock absorber. The dropout 318 also has brake caliper mounts 340 to which brake callipers are attachable. As the axle 326 is offset in the forward direction, the brake calliper mounts 340 are relatively short for proper positioning on a brake disk.

Single sided fork of FIG. 26 has recirculating bearing casings 342 fastened to the outer tube 344 with coupling 346, and are removable from the exterior thereof.

Dropout 348 is attached to the bottom end of the inner tube 350. A brake caliper mount 352, longer than the one of FIG. 24, is attached adjacent the axle 354. A brake calliper 343 is supported to the mount 352 and is associated with brake disk 345 for breaking rotation thereof.

FIG. 27 shows an alternative embodiment for the leg 356 of a single sided fork, which employs non-recirculating needle bearings 361 that move axially between the inner tube 358 and the outer tube 360, as disclosed in U. S. Patent No. 5,320,374. The needle bearings 361 are housed in bearing cage 362, shown in FIGs. 28 and 29. The needle bearings 361 roll along flat faces or races 364 on the outside of the inner tube 350 and on the inside of the inner tube 350. As the inner and outer tubes telescope with respect to each other, the bearings 361 reduce telescoping friction and restrict relative axial rotation of the tubes.

One of ordinary skill in the art can envision numerous variations and modifications. For example, the inner tube can be mounted to the handlebars on the top of the fork, with the outer tube mounted to the wheel, on the bottom of the fork. Also, a removable key 366 with a bearing seat 368 adjacent a rim 370 for retaining a bearing 210 can be mounted on the end of an axle 372, against a rim 374, as shown in FIG. 30. Also, the axle can be screwed with vertical fasteners to the bottom of the lower single sided fork tube. All of these modifications are contemplated by the true spirit and scope of the following claims.