Abstract:
An apparatus for securing a personal transport vehicle (PTV) such as a motorcycle or ATV on a truck bed or the ground includes a pair of handlebar struts each adjustable to a length fixable by a first key lock, an upper hook lockable by a second key lock to a handlebar of a PTV, a lower hook securable to an anchor member fixed to a truck or the ground, by a third key lock, and a cross-lock arm adjustable to a length fixable by a cross-lock arm key lock. Each cross-lock arm has at one end a swivelable hook attachable to a PTV, and at the other end a fixed hook for engaging an eye plate of the strut. A pair of struts is used to secure a single PTV using a pair of cross-lock arms or a pair of PTV&#39;s joined by a single cross-lock arm.

Description:
[0001]    This application is a divisional of and claims priority to U.S. application Ser. No. 11/438,102, filed May 19, 2006. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    A. Field of the Invention 
         [0003]    The present invention relates to accessory devices for use with All Terrain Vehicles (ATV&#39;s), motorcycles or similar personal transport vehicles. More particularly, the invention relates to an apparatus for securing in an upright position a vehicle such as an ATV or motorcycle, or pairs thereof, within the bed of a truck used to transport the vehicle, or to an anchor member such as an elongated channel or tube placed on the ground, to discourage theft of the vehicle. 
         [0004]    B. Description of Background Art 
         [0005]    Motorcycles and ATV&#39;s are routinely transported in the beds of pick-up trucks to and from the owner&#39;s residences to destinations such as off-road recreational areas. Customarily, an ATV or motorcycle is positioned upright in a truck bed, and secured therein by tie-down cords, cables or the like. Typically, a tie-down cord is fastened at one or both ends thereof to a bracket or other part of a truck bed or body, the cord being fastened to or looped around a component of the ATV or cycle. To ensure that the ATV or motorcycle remains securely positioned relative to the truck bed as a conveying vehicle accelerates, decelerates or turns, it is usually required that the tie-down cords exert a substantial compressive force on the tires and suspension components of the ATV or motorcycle. The tie-down forces can be sufficiently large to cause fatigue or distortion of suspension components and tires of an ATV or motorcycle. 
         [0006]    Another problem encountered by owners of ATV&#39;s or motorcycles is the possibility that these vehicles might be stolen when left unattended at remote locations, or even from the owner&#39;s truck. In view of the foregoing problems, a variety of devices have been disclosed which are intended to secure ATV&#39;s or motorcycles against shifting within a vehicle used to transport the vehicles. Also, devices have been disclosed which are intended to discourage theft of ATVs or motorcycles, either from the bed of a transporting vehicle, from a parking location on the ground, or both. The following U.S. patents and patent application publications disclose devices intended to accomplish one or more of the foregoing objectives: 
         [0007]    Martin, U.S. Pat. No. 5,813,259, Locking Device: Discloses a locking stand for preventing theft of portable objects, such as boats, ATV&#39;s and bicycles. 
         [0008]    Weaver, U.S. Pat. No. 6,036,417, Mar. 14, 2000, Stabilizing Arm For All-Terrain Vehicle Discloses a stabilizing arm for stabilizing an All Terrain Vehicle in the bed of a pickup truck. 
         [0009]    Rekemeyer, U.S. Pat. No. 6,058,749, May 9, 2000, Combination Anti-Skid Anti-Theft And Vehicle Lifting System. 
         [0010]    Fotou, U.S. Pat. No. 6,065,914, May 23, 2000, Apparatus For Securing A Vehicle. 
         [0011]    Voiculescu, U.S. Pat. No. 6,524,041, Feb. 25, 2003, Locking Ratchet For A Lashing Mechanism: Discloses a tie-down assembly for securing an article by a strap. 
         [0012]    Trauthwein, U.S. Pat. No. 6,655,885, Dec. 2, 2003, Tie Down BarFor Motorcycles: Discloses a tie down device for securing modern sport type motorcycles having a full fairing to a truck or trailer bed without damaging the fairing. 
         [0013]    Jackson, Sr., U.S. Pat. No. 6,715,972, Apr. 6, 2004, Rigid Tie-Down Device For Securing A Two-Wheeled Vehicle: Discloses a non-compressing device for securing a two-wheeled vehicle to a towing apparatus. 
         [0014]    Bosley, U.S. Publication No. 2003/0059269, Mar. 27, 2003, Cargo Restraint Apparatus: Discloses a cargo restraint apparatus for use to secure a load on a vehicle which includes a frame assembly, a reel, and an elongated strap. 
         [0015]    Quinn et al., U.S. Publication No. 2004/0011096, Jan. 22, 2004, Theft Deterrent-Device For ATVs (All Terrain Vehicles): Discloses a method of securing a vehicle in place on the ground which includes an articulating head and an auger for burrowing into the ground. 
         [0016]    The present invention was made to provide a versatile ATV/motorcycle lockdown apparatus which is useable to secure one or more small vehicles such as ATV&#39;s or motorcycles in an upright disposition within the bed of a truck or trailer used to transport the vehicle, or in place on the ground. 
       OBJECTS OF THE INVENTION 
       [0017]    An object of the invention is to provide an apparatus for mechanically securing a personal transport vehicle such as a motorcycle or All Terrain Vehicle (ATV) in a fixed position in a truck bed to prevent movement of the vehicle within the truck bed when the truck is in motion. 
         [0018]    Another object of the invention is to provide an ATV/motorcycle lockdown apparatus which is useable both to secure a personal transport vehicle such as an ATV or motorcycle, or pairs of such vehicles, within the bed of a truck or on the ground, to thwart theft of the vehicle or vehicles. 
         [0019]    Another object of the invention is to provide an ATV/motorcycle lockdown apparatus which does not require the use of tie down cords. 
         [0020]    Another object of the invention is to provide an ATV/motorcycle lockdown apparatus which does not exert compressive forces on suspension components or tires of a vehicle secured by the apparatus. 
         [0021]    Another object of the invention is to provide an ATV/motorcycle lockdown apparatus which is useable to support ATV&#39;s, motorcycles and similar small personal transport vehicles in an upright position in trucks, trailers and on the ground, and which may also be used as a work stand to support such a vehicle while maintenance or repair operations are performed thereon. 
         [0022]    Another object of the invention is to provide an ATV/motorcycle lockdown apparatus which is readily operable by a single individual using a key. 
         [0023]    Various other objects and advantages of the present invention, and its most novel features, will become apparent to those skilled in the art by perusing the accompanying specification, drawings and claims. 
         [0024]    It is to be understood that although the invention disclosed herein is fully capable of achieving the objects and providing the advantages described, the characteristics of the invention described herein are merely illustrative of the preferred embodiments. Accordingly, we do not intend that the scope of our exclusive rights and privileges in the invention be limited to details of the embodiments described. We do intend that equivalents, adaptations and modifications of the invention reasonably inferrable from the description contained herein be included within the scope of the invention as defined by the appended claims. 
       SUMMARY OF THE INVENTION 
       [0025]    Briefly stated, the present invention comprehends a lockdown apparatus for temporarily securing a personal transport vehicle such as a motorcycle, All Terrain Vehicle (ATV), or pairs of such vehicles in place on a support surface such as a truck bed or the ground. An ATV/motorcycle lockdown apparatus according to the present invention includes a pair of elongated handlebar support struts and one or two shorter cross-lock arms which are used to secure in an upright position two motorcycles in a side-by-side disposition, a single motorcycle, or ATV. According to the invention, a pair of handlebar support struts and a pair of cross-lock arms are used to secure a single motorcycle or ATV. 
         [0026]    A preferred method of using the lockdown apparatus of the present invention to secure ATV&#39;s or motorcycles in place on the ground utilizes an anchor member such as a longitudinally elongated rectangular steel tube or channel which is provided with spaced apart perforations through a longitudinally disposed wall thereof, the anchor member being disposed transversely on the ground in front of the handlebars of the vehicle or vehicles to be secured. When the apparatus is used to secure ATV&#39;s or motorcycles to a truck bed, existing laterally spaced apart perforations in a forward part of the truck bed may be used. Alternatively, a steel tube or channel, or similar anchor member, may be temporarily or permanently secured to the truck bed in a transversely disposed orientation. 
         [0027]    According to the invention, each handlebar support strut includes an elongated, straight cylindrically-shaped member which is telescopically adjustable to a desired length, and provided with one or more key locks to secure the strut at its adjusted length. Each strut is provided at an upper end thereof with a J-hook of relatively large cross-section and a U-shaped opening which is hooked over and locked onto a separate handlebar of a vehicle to be secured. Each strut is provided at the lower end thereof with a relatively smaller J-hook which is of relatively smaller circular cross-section and of an appropriate diameter to be insertably receivable in a selected perforation of a transversely disposed steel channel or tube, or other anchor member. Preferably, the lower J-hooks of the two handlebar struts are hooked into a pair of perforations located equidistant from opposite sides of a vertical longitudinally disposed center plane of a motorcycle or ATV to be secured. The handlebar support struts are disposed obliquely upwardly and inwardly from the anchor member towards the vehicle center plane. The larger J-hooks at the upper ends of the handlebar support struts are hooked around intermediate portions of left and right handlebars of the motorcycle or ATV. Each upper J-hook is secured in place to a handlebar by a first, upper key lock, the telescopically adjustable length of the handlebar support strut is secured by a second, intermediate key lock, and the lower J-hook is inserted into a perforation through the anchor member and secured there by a third, lower key lock. 
         [0028]    A preferred embodiment of a telescopically adjustable handlebar support strut according to the present invention includes an intermediate tubular section, and a cylindrical upper bar section which is swivelably mounted to an upper end of the intermediate tubular section by a ball-and-socket type joint. The upper J-hook is telescopically mounted to the exterior of the upper end of the upper bar. 
         [0029]    A preferred handlebar support strut construction according to the present invention also includes a lower cylindrical bar section which fits telescopically within a coaxial inner bore of the intermediate tubular section, and secured at adjustable extensions from the tubular section by the intermediate key lock. The lower J-hook protrudes from a lower transverse end of the lower cylindrical bar section, and the opening of the lower J-hook is closed after the hook is inserted through a perforation of an anchor member, by sliding a sleeve mounted on the outside of the lower cylindrical bar section downwardly towards the inward curved end of the hook and securing the sleeve in that position by the lower key lock. 
         [0030]    Each cross-lock arm of the lockdown apparatus according to the present invention includes an elongated, straight tubular section which has at a first end thereof a first longitudinally disposed upper C-hook which is fixed to and protrudes from a first transverse end of the tubular section. The cross-lock arm also includes an elongated cylindrical bar which is telescopically received in a coaxial bore disposed through the tubular section, the bar having an extension distance from the lower transverse end of the tubular section which is telescopically adjustably and secureable at a desired extension by a cross-lock arm key lock. The lower end of the cylindrical bar has protruding from a lower transverse end thereof a second longitudinally disposed C-hook similar in construction to the first C-hook, but which is swivelably joined to the bar. 
         [0031]    When the ATV/motorcycle lockdown apparatus according to the present invention is used to secure a single vehicle, a pair of cross-lock arms are used, with the first, fixed C-hook of each cross-lock arm hooked into a perforation through an eye plate which protrudes radially from a floating collar assembly that is slidably mounted on the outside of the lower cylindrical bar section, or on intermediate tubular section of, each handlebar strut. The floating collar assembly is slidably adjustable on the lower cylindrical bar section or intermediate tubular section of a handlebar strut, and a selected longitudinal position thereon maintained by a spring-loaded detent button which protrudes into a selected one of a plurality of longitudinally spaced apart circular grooves or perforations provided in the outer circumferential wall surface of the cylindrical bar or tube on which the collar is mounted. Each cross-lock arm is disposed obliquely rearwardly and inwardly towards a center plane of a vehicle, from a floating collar assembly on a handlebar strut, and the second, swivelable C-hook thereof hooked around a lower chassis or engine component of a motorcycle or ATV, and secured in that position by the cross-lock arm key lock which protrudes radially from a lower end of the cross-lock arm and locks the arm at a selected extension length. 
         [0032]    When the lockdown apparatus according to the present invention is used to secure a pair of motorcycles or ATV&#39;s side-by-side, the handlebar struts are deployed in a fashion similar to that used to secure a single vehicle, except that one handlebar strut is attached to one handlebar, e.g., the right handlebar of a first, right-hand vehicle, while the other handlebar strut is attached to the opposite handlebar of the adjacent vehicle. Also, when the lockdown apparatus according to the present invention is used to secure two vehicles, a single cross-lock arm is disposed horizontally between inner facing parts of two adjacent vehicles, and the two C-hooks at the opposite end of the cross-lock arm secured to the two vehicles. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]      FIG. 1  is a front perspective view of a basic embodiment of an ATV/motorcycle lockdown apparatus according to the present invention showing two handlebar struts and two cross-arm locks of the apparatus in use to secure a motorcycle to a transversely disposed perforated angle iron used as an anchor member. 
           [0034]      FIG. 2  is a side perspective view of the apparatus of  FIG. 1 . 
           [0035]      FIG. 3  is a fragmentary side elevation view of the apparatus of  FIGS. 1 and 2 , showing engagement of a chassis component of the motorcycle by a swivelable C-hook of a cross-arm lock of the apparatus. 
           [0036]      FIG. 4  is a fragmentary perspective view of the apparatus of  FIGS. 1 and 2  showing engagement of a handlebar of the motorcycle by an upper J-hook of a handlebar strut of the apparatus. 
           [0037]      FIG. 5  is a rear perspective view showing the apparatus of  FIG. 1  fastened to a pair of tie-down brackets in the lower front portion of a pickup truck bed to secure a motorcycle in the truck bed. 
           [0038]      FIG. 6  is a front perspective view showing the apparatus of  FIG. 1  in use to secure a pair of motorcycles to a transversely disposed anchor member consisting of a perforated angle iron beam. 
           [0039]      FIG. 7  is a perspective view of a handlebar strut and cross-arm lock comprising two different components of the lockdown apparatus of  FIG. 1 . 
           [0040]      FIG. 8  is a fragmentary, partly sectional view of the apparatus of  FIG. 7  on an enlarged scale. 
           [0041]      FIG. 9  is a perspective view of a modification of the apparatus of  FIG. 1 , in which a handlebar strut thereof has a modified upper J-hook. 
           [0042]      FIG. 10  is a side elevation view of a handlebar strut component of the apparatus of  FIG. 7 , partly in longitudinal section. 
           [0043]      FIG. 11  is a fragmentary, partly sectional view of the handlebar strut of  FIG. 10 , showing details of an upper swivel joint thereof. 
           [0044]      FIG. 12  is a fragmentary, partly sectional view of the handlebar strut of  FIG. 10 , showing details of a floating collar assembly thereof. 
           [0045]      FIG. 13  is a fragmentary, partly sectional perspective view of the floating collar assembly of  FIG. 10 , on an enlarged scale. 
           [0046]      FIG. 14  is a transverse sectional view of the floating collar assembly of  FIG. 13 . 
           [0047]      FIG. 15  is a fragmentary, partly sectional view of the handlebar strut of  FIG. 10 , showing details of a lower J-hook thereof. 
           [0048]      FIG. 16  is a fragmentary, partly sectional perspective view of the handlebar strut of  FIG. 10 , showing details of an upper J-hook and locking mechanism thereof. 
           [0049]      FIG. 17  is a fragmentary partly sectional perspective view of the handlebar strut of  FIG. 10 , showing details of an upper swivel joint thereof. 
           [0050]      FIG. 18  is a fragmentary, partly sectional perspective view of the handlebar strut of  FIG. 10 , showing details of floating collar assembly thereof. 
           [0051]      FIG. 19  is a perspective view of the cross-arm lock of  FIGS. 7 and 9 . 
           [0052]      FIG. 20  is a fragmentary, partly sectional side elevation view of the cross-lock arm of  FIG. 19 , on an enlarged scale, showing details of a swivel joint for a second, lower C-hook thereof. 
           [0053]      FIG. 21  is a fragmentary, enlarged-scale perspective view of the cross-lock arm of  FIG. 20 , showing details of an upper, fixed C-hook thereof. 
           [0054]      FIG. 22  is a partly sectional side elevation view of a modification of the handlebar strut of  FIG. 10 . 
           [0055]      FIG. 23  is a fragmentary, partly sectional view of the modified handlebar strut of  FIG. 22 , showing details of the modified upper J-hook thereof. 
           [0056]      FIG. 24  is a fragmentary, enlarged scale, partly sectional view of the handlebar strut of  FIG. 22 , showing details of an upper swivel joint thereof. 
           [0057]      FIG. 25  is a fragmentary, enlarged scale, partly sectional view of the handlebar strut of  FIG. 22 , showing details of a lower key lock thereof. 
           [0058]      FIG. 26  is a fragmentary, partly sectional view of a further modification of the modified J-hook of  FIG. 23 . 
           [0059]      FIG. 27  is a fragmentary perspective view of another modification of the handlebar strut of  FIG. 10 , in which floating collar assemblies thereof are replaced by an elongated multi-perforation eye plate. 
           [0060]      FIG. 28  is a fragmentary, partly broken-away perspective view of another modification of the handlebar strut of  FIG. 10 , in which an upper swivel joint thereof is lockable at a fixed orientation. 
           [0061]      FIG. 29  is a broken-away view of the lockable swivel joint of  FIG. 28 , on an enlarged scale. 
           [0062]      FIG. 30  is a perspective view of a modification of the cross-lock arm of  FIGS. 7 ,  19  and  20 . 
           [0063]      FIG. 31  is a fragmentary perspective view of an extending, lockable end of the cross-lock arm of  FIG. 30 , on an enlarged scale. 
           [0064]      FIG. 32  is a fragmentary perspective view of a fixed-length end of the cross-lock arm of  FIG. 30 , on an enlarged scale. 
           [0065]      FIG. 33  is a partly sectional perspective view of a handlebar locking arm according to the present invention. 
           [0066]      FIG. 34  is a partly sectional view showing a handlegrip receptacle of the handlebar locking arm of  FIG. 33 , on an enlarged scale. 
           [0067]      FIG. 35  is a front perspective view showing the handlebar locking arm of  FIG. 33  and a pair of handlebar struts in use to secure a street motorcycle. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0068]      FIGS. 1-6  illustrate an ATV/motorcycle lockdown apparatus according to the invention, in use to secure one or two motorcycles to an anchor member on the ground, or to a truck bed. 
         [0069]      FIGS. 7-21  illustrate structural features of a handlebar support strut and cross-lock arm which comprise two components of an ATV/motorcycle lockdown apparatus according to the present invention. 
         [0070]      FIGS. 22-35  illustrate modifications of lockdown apparatus components according to the present invention. 
         [0071]    Referring first to  FIGS. 1 and 2 , an ATV/motorcycle lockdown apparatus  50  according to the present invention may be seen to include an elongated, straight handlebar support strut  51  and a shorter, straight cross-lock arm  71 , pairs of each of which are attached to an elongated anchor member B comprising a length of C-cross-section channel iron, and to a motorcycle A to secure the motorcycle in an upright position on a ground surface C. 
         [0072]    As shown in  FIGS. 1 and 2 , each handlebar support strut  51  includes a relatively long, straight longitudinally centrally located or intermediate tubular section  52 . A shorter elongated straight upper cylindrical bar section  53  protrudes longitudinally from an upper transverse end of intermediate tubular section  52  and as shown is generally coaxially aligned with but pivotably mounted to the central tubular section. Upper cylindrical bar section  53  is terminated at an upper end thereof by an upper J-hook  54  which is hooked around a handlebar D of motorcycle A, e.g., left handlebar Dl. 
         [0073]    Handlebar support strut  51  also has a lower elongated straight cylindrical bar section  55  which is telescopically held within a coaxial bore disposed longitudinally through central tubular section  52 , and extendable from a lower transverse end thereof. Lower cylindrical bar section  55  is terminated at a lower end thereof by a lower J-hook  56  which is of a smaller diameter cross-section than upper J-hook  54 , and of an appropriate size to be insertably receivable through a selected one of a plurality of longitudinally spaced apart perforations E provided through an upright vertical wall F which protrudes upwardly from a base plate G of angle iron channel support anchor member B. 
         [0074]    As shown in  FIGS. 1 and 2 , each handlebar support strut  51  includes an upper cylindrical key lock  57 , which is used to secure upper J-hook  54  to a handlebar D, an intermediate cylindrical key lock  58  to maintain cylindrical lower bar section  55  at a selected predetermined extension length from central tubular section  52 , and a lower cylindrical key lock  59  and sleeve assembly  60  to secure lower J-hook  56  to anchor member B. 
         [0075]    As may be seen best by referring to  FIG. 1 , each handlebar support strut  51  preferably includes at least one, e.g., a lower, floating collar assembly  61  which is longitudinally slidably mounted on the outer cylindrical wall surface of lower cylindrical bar section  55 . Floating collar assembly  61  has protruding radially outwardly therefrom a longitudinally disposed eye plate  62  provided with a perforation  63  through its thickness dimension. 
         [0076]    Referring still to  FIGS. 1 and 2 , it may be seen that each cross-lock arm  71  includes a longitudinally elongated, straight, tubular section  72 . Tubular section  72  of cross-lock arm  71  has a first, fixed C-shaped hook  74  which protrudes longitudinally outward from a first transverse end of the tubular section, the hook having the shape of a uniform thickness bar bent into the shape of a C, one leg of which is fastened to an end of the tubular section, with opposite parallel sides of the bar disposed parallel to and equidistant from a longitudinal center plane of the tubular section. 
         [0077]    As shown in  FIGS. 7 ,  9  and  19 , cross-lock arm  71  also has a cylindrical bar section  75  which is telescopically slidably held within a central coaxial bore  73  disposed longitudinally through tubular section  72 . Cylindrical bar section  75  is telescopically extendible a selectable distance from tubular section  72  of cross-lock arm  71 , and fixed at that distance by a cylindrical key lock  76  which protrudes radially outwards from an outer cylindrical wall surface  77  of the tubular section, near lower transverse end  78  thereof. Cross-lock arm  71  also includes a second, swivelable C-hook  79  similar in construction to C-hook  74 , which protrudes longitudinally outwards from a swivel joint  80  fastened to an end of lower cylindrical bar section  75 . 
         [0078]    As shown in  FIGS. 1-4 , apparatus  50  is used to secure a motorcycle A to an anchor member B such as an elongated length of channel iron which has a base wall G supported on a surface C, such as a ground surface. Anchor member B has a first flange plate F which protrudes vertically upwards from base plate G that has formed through its thickness dimension a plurality of longitudinally spaced apart perforations E, and has a second flange plate H which protrudes upwardly from an opposite longitudinal edge of the base plate. 
         [0079]    As shown in  FIG. 1 , the lower J-hook  56  of each of a pair of spaced apart handlebar struts  51  is hooked into a separate perforation E spaced outwardly from opposite sides of motorcycle A, secured therein by sleeve lock assembly  60 , and locked thereat by lower cylindrical key lock  59 . Also, the length of handlebar strut  51  is adjusted to span the distance between anchored lower J-hook  56  and a handlebar D of motorcycle A by telescopically adjusting central tubular portion  52  of the handlebar strut relative to lower cylindrical bar section  55  thereof, and locking that length adjustment using intermediate key lock  58 . In addition, upper J-hook  54  of each of a pair of handlebar struts  51  is looked around a separate handlebar D of motorcycle A, and secured thereto by upper cylindrical key lock  57 . 
         [0080]    With a pair of handlebar struts  51  fastened at one end to the handlebars D of a motorcycle A and at the other end to anchor member B, each of a pair of cross-lock arms  71  is fastened to an opposite side of the motorcycle and to an adjacent handlebar strut  51 . Thus, as shown in  FIGS. 1 ,  2  and  3 , the fixed C-hook  74  of each cross-lock arm  71  is hooked into perforation  63  through eye plate  62  of a separate floating collar assembly  61 , which has been slidably adjusted to an appropriate longitudinal position on handlebar support strut  51 . 
         [0081]    Cylindrical bar section  75  of each cross-lock arm  71  is then telescopically extended an appropriate longitudinal extension length from tubular section  72  of the cross-lock arm to enable swivelable C-hook  79  to be hooked around a motorcycle component, swiveling the hook on joint  80  if necessary. Cylindrical lock  76  of each cross-lock arm  71  is then operated by a key inserted into the lock to a locked position which secures cylindrical bar section  75  of the cross-lock arm at an appropriate extension distance between floating collar assembly  61  and the swivelable C-hook  79  of the cross-lock arm, thus securing the motorcycle in place as shown in  FIGS. 1-4 . 
         [0082]    As shown in  FIG. 5 , the manner of using apparatus  50  to secure a motorcycle to the bed of a truck is substantially identical to the manner of securing a motorcycle to an anchor member placed on the ground, as described above and shown in  FIGS. 1-4 . However, to secure a motorcycle to a truck bed J, the ends of lower J-hooks  56  of a pair of handlebar support struts  51  are secured in holes L through a pair of laterally spaced apart brackets K located in a lower front portion of the bed of the truck. 
         [0083]      FIG. 6  illustrates the manner of using apparatus  50  to secure a pair of upright, side-by-side motorcycles to a transversely disposed perforated channel member placed on the ground, or to a truck bed. As shown in  FIG. 6 , a pair of handlebar support struts  51  is used exactly as described above to support left and right motorcycle handlebars, but in this case, the left handlebar of a “left” motorcycle and the right handlebar of a “right” motorcycle located adjacent to the right side of the left motorcycle. A single cross-lock arm  71  is then connected between laterally spaced apart and aligned components of the two motorcycles, and locked in place b operating cross-lock arm key lock  76 . 
         [0084]      FIGS. 7 ,  8  and  10 - 18  illustrate construction details of handlebar support strut  51 . 
         [0085]    As may be seen best by referring to  FIGS. 7 ,  8  and  10 , upper cylindrical bar section  53  of handlebar support strut  51  is preferably connected to upper transverse end  91  of central tubular section  52  of the handlebar support strut by an upper swivelable joint  92 . As shown in  FIG. 11 , swivelable joint  92  includes a cylindrically-shaped bushing  93  which is retained coaxially within a central coaxial bore  94  disposed longitudinally inwards from upper transverse end  91  of central tubular section  52 . Bushing  93 , of a type sometimes referred to as a Heim Ball Outer Race, has a generally spherically-shaped cavity  95  located concentrically within the bushing, the cavity being truncated equidistant from north and south poles thereof by inner and outer transverse faces  96 ,  97  to form inner and outer circular bores  98 , 99 , respectively, which communicate with the cavity. 
         [0086]    Upper swivelable joint  92  includes a ball  100  which has parallel, equal diameter truncating faces (Heim Ball Inner Race) which fits rotatably and concentrically within spherical cavity  95  within bushing  93 , the ball being truncated by parallel flat opposed circular faces  101 ,  102 . Ball  100  has disposed perpendicularly through truncating faces  101 ,  102  thereof a coaxial longitudinally disposed cylindrically-shaped bore  103 , which receives therethrough an Allen bolt  104 . 
         [0087]    Allen bolt  104  has a shank 104 A which is disposed longitudinally outwardly through bore  103  of ball  100 , and has an enlarged head  105  which seats on inner circular face  101  of the ball. Shank  104 A has a smooth upper portion  106  which protrudes through outer face  102  of the ball, and a lower portion  107  provided with external helical threads  108 . Threaded lower shank  107  of Allen bolt  104  protrudes longitudinally outwardly from upper transverse end  91  of central tubular section  53 , and is disposed longitudinally through the central coaxial bore  109  of a generally cylindrically-shaped grommet  110 . 
         [0088]    Grommet  110  is made of a resilient material such as an elastomeric polyurethane, and has parallel inner and outer transverse faces  111 ,  112 , respectively. Threaded lower shank portion  107  of Allen bolt  104  protrudes outwardly through outer transverse face  112  of grommet  110 , and is threadingly received with a blind threaded bore  113  that protrudes inwardly into lower transverse face  114  of upper cylindrical bar section  53 . Constructed as described above, joint  92  functions as a swivelable, ball-and-socket type joint which enables upper cylindrical bar section  53  to be oriented at a desired angle relative to central tubular section  52  of handlebar support strut  51 . Preferably, swivelable joint  92  includes a cylindrically-shaped steel spacer sleeve  115  which fits coaxially within bore  109  of grommet  110 , the spacer having a longitudinally disposed coaxial bore  116  which receives lower shank  107  of Allen bolt  104 . Spacer sleeve  115  ensures that a minimum distance is maintained between cylindrical bar section  53  and central tubular section  52  of strut  51 . 
         [0089]    As will be described in detail below, a modification of handlebar support  51  in which swivelable joint  92  is replaced by a lockable joint, preferably is used when apparatus  50  is used to secure a pair of motorcycles. 
         [0090]    The structure and function of upper J-hook  54 , which is longitudinally slidably mounted to an upper end portion of upper cylindrical bar section  53  of handlebar support strut  51 , may be best understood by referring to  FIG. 16 . 
         [0091]    As shown in  FIG. 16 , upper J-hook  54  has a straight longitudinally disposed, inner leg  117  which protrudes radially outwards from an outer cylindrical wall surface  118  of cylindrical upper key lock  57 , which in turn protrudes radially outwardly from the outer cylindrical wall surface  119  of a cylindrically-shaped sleeve  120  that is longitudinally slidably mounted on the outer cylindrical surface  121  of upper cylindrical bar section  53  of handlebar support strut  51 . Straight inner leg  117  of J-hook  54  is disposed parallel to the longitudinal axis of upper cylindrical bar section  53  of handlebar support strut  51 , and extends longitudinally outwards of outer transverse annular end wall  122  of sleeve  120 , sufficiently far to also extend longitudinally outwards of outer transverse circular end wall  123  of the cylindrical bar section, even with the outer transverse end wall of the sleeve slid rearward or inwardly of the outer end of the cylindrical bar section, as shown in  FIGS. 10 and 16 . 
         [0092]    As may be seen best by referring to  FIG. 16 , straight inner leg  117  of upper J-hook  54  is terminated by an arcuately curved U-shaped end portion  124  which curves radially inwardly, towards the longitudinal axis of upper cylindrical bar section  53 , and rearwardly, the end portion having a generally straight, short outer leg  125  which is disposed parallel to a longitudinal center line of upper cylindrical bar section, on a side of the center line opposite to that of straight inner leg  117  of the upper J-hook. With this construction, curved end portion  124  of J-hook  54  has a concave, generally U-shaped opening  126  which confronts outer transversely disposed circular end wall  123  of upper cylindrical bar section  53 . 
         [0093]    As may be seen best by referring to  FIGS. 8 ,  10  and  16 , sleeve  120  has a central longitudinally disposed coaxial bore  127  which has an inner cylindrical wall surface  127 A that is longitudinally slidable on outer cylindrical wall surface  121  of upper cylindrical bar section  53  of handlebar support strut  51 . Preferably, sleeve  120  is prevented from rotating on upper cylindrical bar section  53  by providing a longitudinally disposed slot  128  in the outer cylindrical wall surface  121  of the upper cylindrical bar surface, and a guide pin  129  which protrudes radially inwardly into the slot from a radially disposed hole  130  through cylindrical wall  131  of sleeve  120 . 
         [0094]    As shown in  FIGS. 8 and 16 , outer cylindrical wall surface  121  of upper cylindrical bar section  53  is provided with a plurality of regularly spaced apart, blind indexing bores  132 , which are adapted to insertably receive a locking pin  132 A (see  FIG. 23 ) that is advanceable radially inwardly into a selected bore by operating upper cylindrical key lock  57  with an appropriate key. This construction enables a vehicle structural member such as a handlebar to be engaged within U-shaped opening  126  of upper J-hook  54 , between U-shaped end portion  124  of the J-hook and outer transverse circular end wall  123  of upper cylindrical bar section  53  of handlebar support strut  51 . 
         [0095]    In a preferred embodiment, to prevent marring a handlebar or other structural members engaged by J-hook  54 , outer transverse circular end wall  123  of upper cylindrical bar section  53  is fitted with a resilient bumper stop  133 . In one embodiment of handlebar support strut  51 , shown in  FIGS. 8 ,  10  and  16 , bumper stop  133  comprises a bolt  134  which has an enlarged resilient head  135  and a threaded shank  136  which is threadingly received in a threaded blind bore  137  that extends longitudinally inward into outer circular face  123  of upper cylindrical section  53 . 
         [0096]      FIGS. 7 and 10  illustrate structural details of handlebar support strut  51  that enable lower cylindrical bar section  55  to be extended an adjustable distance outwards or below the lower transverse end  140  of central tubular section  52  of the handlebar support strut. As shown in  FIGS. 7 and 10 , a plurality of longitudinally regularly spaced apart, blind indexing bores  141  are formed in the outer cylindrical wall surface  142  of lower cylindrical bar section  55 . As is also shown in  FIGS. 7 and 10 , intermediate cylindrical key lock  58  protrudes radially outwardly from outer cylindrical wall surface  143  of central tubular section  52 , longitudinally inwards of lower transverse end  140  of the central tubular section. Intermediate key lock  58  has a locking pin  144  which is advanced radially inwardly through a perforation  145  through cylindrical wall  146  of central tubular section  52  when operated with a key, the pin being insertably received in a selected blind index bore  141  and thus maintaining a selected extension distance of lower cylindrical bar  55 . 
         [0097]      FIGS. 7 ,  10  and  15  illustrate structural details of lower J-hook  56  of handlebar strut  51  and the manner of securing the J-hook through a perforation of an anchor member. As shown in those figures, lower cylindrical key lock  59  associated with lower J-hook  56  protrudes radially outwardly from the outer cylindrical wall surface  149  of a cylindrically-shaped, lower J-hook locking sleeve  150 , which is longitudinally slidably mounted on the outer cylindrical surface  151  of lower cylindrical bar section  55  of handlebar support strut  51 . Lower J-hook  56  has a straight, longitudinally disposed leg  147  which fits slidably in a central blind coaxial bore  148  in lower transverse end face  151  of lower cylindrical bar section  55 . Straight inner leg  147  of lower J-hook  56  is terminated at a longitudinally outwardly located end thereof by an arcuately curved, U-shaped end portion  154  which curves rearwardly, the end portion having a generally straight leg  155  which is disposed parallel to and adjacent to outer cylindrical wall surface  151  of lower cylindrical bar section  55 . With this construction, curved end portion  154  of lower J-hook  56  has a concave, generally U-shaped opening  156  which confronts outer circular end wall  153  of lower cylindrical bar section  55 . 
         [0098]    As shown in  FIGS. 7-10 , longitudinally disposed coaxial bore  148  of lower J-hook locking sleeve  150  has an inner cylindrical wall surface which is longitudinally slidable on outer cylindrical wall surface  142  of lower cylindrical bar  55  of handlebar strut  51 . Preferably, sleeve  150  is prevented from rotating on lower cylindrical bar section  55  by providing a longitudinally disposed slot  158  in the outer cylindrical wall surface  142  of the lower cylindrical bar section, in combination with a guide pin  159  which protrudes radially inwardly into the slot from a radially disposed hole  160  through cylindrical wall  149  of sleeve  150 . 
         [0099]    As shown in  FIGS. 7 ,  9  and  15 , blind indexing bores  141  in the outer cylindrical wall surface  142  of lower cylindrical bar section  55 , are adapted to insertably receive a locking pin  163  which is advanced radially inwardly into a selected bore by operating lower cylindrical key lock  59  with an appropriate key. This construction enables lower J-hook  56  to be inserted into a perforation through anchor member, and secured therein by sliding sleeve  150  inwardly on lower cylindrical bar section  55  to thereby slide inwardly disposed leg  147  of hook  56  into blind bore  148  in lower transverse end  153  of bar  55 , and operating lower key lock  59 . 
         [0100]    As shown in  FIGS. 1 and 7 , handlebar support strut  51  of ATV/motorcycle lockdown apparatus  50  according to the present invention preferably includes at least one floating collar assembly  61  which is slidably mounted on lower cylindrical bar  55  of the handlebar strut. Optionally, floating collar assembly  61  may be slidably mounted on central tubular section  52  of handlebar strut  51 , or as shown in  FIGS. 1 and 7 , an additional floating collar assembly  61 A may be slidably mounted on central tubular member  52  of the handlebar strut. The quantity and location of floating collar assemblies  61  positioned on handlebar support strut  51  is selectable by a user of apparatus  50  as is appropriate for securing a particular ATV or motorcycle to a particular support anchor or transport vehicle. 
         [0101]    As may be seen best by referring to  FIGS. 13 ,  14  and  16 , floating collar assembly  61  includes a cylindrical sleeve  164  which has therethrough a central longitudinally disposed coaxial bore  165 . Sleeve  164  has protruding radially outwardly from outer cylindrical wall surface  166  thereof an eye plate or link  62  which has therethrough a transversely disposed aperture or eye  63 . As shown in  FIG. 16 , aperture  63  has a generally rectangular outline shape including an upper, radially outwardly located longitudinally disposed edge wall  167 , inner and outer transversely disposed, longitudinally spaced apart edge walls  168 ,  169 , and a lower, radially inwardly located longitudinally disposed edge wall  170  proximate outer cylindrical wall surface  166  of sleeve  164 . 
         [0102]    As may be seen best by referring to  FIGS. 13 and 14 , in addition to  FIG. 16 , inner longitudinally disposed edge wall  170  of floating collar assembly  61  has protruding radially outwardly therethrough, into eye  63 , a hollow cylindrically-shaped, detent button boss  171 . Detent button boss  171  has a central, radially disposed, coaxial bore  172  which penetrates upper longitudinally disposed wall  173  of the boss, and inner cylindrical wall surface  174  of sleeve  164 , thus communicating with longitudinally disposed bore  165  through the sleeve. Radially disposed bore  172  through detent button boss  171  radially slidably receives therein a cylindrical locking pin  176  which has at an upper, radially outwardly located transverse end thereof a transversely disposed, circular finger knob  177 . Cylindrical locking pin  176  also has formed in the outer cylindrical wall surface  178  thereof a pair of longitudinally spaced apart, annular ring-shaped outer and inner grooves  179 ,  180 . Also, boss  171  has disposed transversely through cylindrical wall  181  thereof an aperture  182 . Aperture  182  contains a steel detent ball  183 , which is urged inwardly beyond the inner cylindrical wall surface  184  of the boss, into an outer or inner annular detent grooves  179 ,  180  of locking pin  176 , by a C-shaped leaf spring  185 . 
         [0103]    With locking pin  176  retracted radially outwards as shown in  FIGS. 13 and 14 , and detent ball  183  urged resiliently into lower, inner annular detent groove  180 , sleeve  164  of floating collar assembly  61  is longitudinally slidable on either lower cylindrical bar  55  or tubular central section  52  of handlebar support strut  51 . When floating collar assembly  61  is adjusted to a desired longitudinal position on lower cylindrical bar  55  or tubular central section  52 , finger knob  177  is pushed radially inward, thus extending inner radial end  186  of locking pin  176  into a selected blind indexing bore  141  in bar  55 , or through a selected index hole  145  through wall  146  of central tubular section  52 . Pushing finger knob radially inwards causes detent ball  183  to engage upper, outer detent groove  179 , thus securing the floating collar assembly  61  at a selected longitudinal position. 
         [0104]      FIGS. 9 ,  22  and  23  illustrate a modification of handlebar support strut  51  described above. As shown in  FIGS. 9 ,  22  and  23 , modified handlebar support strut  191  has a modified upper J-hook  194  in which the inner leg  197  thereof corresponding to inner straight leg  117  of J-hook  54  shown in  FIG. 16 , has in side elevation view a serpentine or S-shape, including a straight longitudinally inwardly located segment  198  disposed rearwardly from outer cylindrical wall surface  118  of cylindrical upper key lock  57 , the rear leg segment being parallel and relatively close to a modified upper cylindrical bar  53 A of the modified handlebar strut. 
         [0105]    Inner leg  197  of modified upper J-hook  194  also has a relatively short serpentinely curved intermediate segment  199  which angles radially outwardly from an outer longitudinal end portion of straight rear segment  198 , and a straight longitudinally outwardly located segment  200  which protrudes longitudinally outwards from the intermediate segment, parallel to but disposed radially outwardly from outer cylindrical wall surface  121 A of modified upper cylindrical bar section  53 A. 
         [0106]    Outer straight segment  200  of modified J-hook  194  is disposed parallel to the longitudinal axis of upper cylindrical bar section  53 A of modified handlebar support strut  191 , and extends longitudinally outwards of outer transverse annular end wall  122  of sleeve  120  that supports upper key lock  57 , sufficiently far to also extend longitudinally outwards of outer transverse circular end wall  123 A of the upper cylindrical bar section, even with the outer transverse end wall of the sleeve positioned rearwardly or inwardly of the outer end of the cylindrical bar segment as shown in  FIGS. 9 ,  22  and  23 . 
         [0107]    As may be seen best by referring to  FIG. 23 , outer straight leg segment  200  of modified upper J-hook  194  is terminated by an arcuately curved U-shaped end portion  204  which curves radially inwardly towards the longitudinal axis of upper cylindrical bar section  53 A, and rearwardly, the end portion having a generally straight, short outer leg  205  which is coaxially aligned with the longitudinal center line of the upper cylindrical bar section. As shown in  FIG. 23 , circular transverse end wall  123 A of upper cylindrical bar section  53 A has formed therein a coaxial blind bore  206  of a suitable diameter to insertably receive longitudinally inwardly directed leg  205  of modified upper J-hook, thus securing a handlebar or other structural member within U-shaped opening  206  of the J-hook, when sleeve  120  is slid longitudinally inwardly and upper key lock  57  operated 
         [0108]    The structure and function of cross-lock arm  71  may be best understood by referring to  FIGS. 7 ,  19  and  20 . As shown in those figures, and described briefly above, cross-lock arm  71  includes an elongated, straight tubular section  72  which has protruding longitudinally from an outer cylindrical wall surface  77  thereof, proximate a first transverse end  211  thereof, a fixed C-shaped hook  74 . Fixed hook  74  has front and rear parallel, longitudinally disposed sides  212 ,  213 , which are spaced equidistant from a longitudinal center plane through tubular section  72  of cross-lock arm  71 . Fixed hook  74  includes a short, straight, longitudinally inwardly located section  214  which is secured to outer cylindrical wall surface  216  of tubular section  72 , as for example, by a welded joint. Hook  74  also has extending longitudinally from straight section  214  thereof an arcuately curved outer section  215  which has a generally transversely oriented concave opening  216  and an outer tang  217 . Although the exact construction of hook  74  is not critical, a suitable construction, shown in  FIG. 7 , utilizes a length of arcuately bent steel bar stock. 
         [0109]    Referring still to  FIGS. 7 ,  19  and  20 , it may be seen that cylindrical bar section  75  of cross-lock arm  71  is telescopically adjustable within central coaxial bore  73  disposed longitudinally through tubular section  72 , and locked at a selected longitudinal extension distance from transverse end wall  78  of the tubular section, by cross-lock arm key lock  76 , utilizing a construction exactly similar in structure and function to that of lower cylindrical bar section  55  and tubular central section  52  of handlebar upper strut  51 , as described above. Also, swivel joint  80 , which joins a transverse end  219  of lower cylindrical bar section  75  to swivelable C-hook  79 , is exactly similar in structure and function to swivel  92  of handlebar support strut  51 , as described above. 
         [0110]      FIG. 26  illustrates a further modification of J-hook  194  of modified handlebar strut  191 , as shown in  FIGS. 9 ,  22  and  23 , and described above. As shown in  FIG. 26 , modified J-hook  294  includes a sleeve  220  which has a central coaxial bore  227  that slidably receives upper cylindrical bar section  53  of handlebar strut  191 . Sleeve  220  has a generally cylindrically-shaped, longitudinally disposed tubular section  222 , and a hollow outer key lock cylinder  223  which protrudes radially outwardly from outer wall surface  224  of the tubular section. Radially disposed cylinder  223  of sleeve  220  has disposed therethrough a coaxial bore  224  in which is fitted cylindrical key lock  57 . Key lock  57  has a locking pin  225  that is advanceable, by turning a key  226 , into a selected blind bore  133  in outer cylindrical wall surface  121  of cylindrical bar  53 . 
         [0111]    As shown in  FIG. 26 , sleeve  220  of modified J-hook  294  also has a longitudinally disposed cylindrical boss  227  which protrudes perpendicularly from outer cylindrical wall surface  228  of key lock cylinder  223  and which is disposed parallel to bore  227  of sleeve  220 . Longitudinally disposed boss  227  has a transversely disposed end face  229  which is penetrated by a blind, threaded bore  230  that is disposed parallel to the longitudinal axis of sleeve  220  and bar  53 . Threaded bore  230  threadingly receives an externally threaded straight inner leg  296  of J-hook  295 , thus enabling the extension of inner opening  306  of the J-hook relative to transverse end  307  of sleeve  220 , and therefore relative to the transverse end of bar  53 , to be adjusted by threadingly advancing inner leg  296  within bore  230 . 
         [0112]      FIG. 27  illustrates a modification of handlebar strut  51  shown in  FIGS. 8-10  and described above. Modified handlebar strut  51 B uses a modified upper tubular section  52 B, in which floating collar assemblies  61  are replaced by a longitudinally disposed central eye plate  62 V which has through its thickness dimension a plurality of longitudinally spaced apart perforations  63 V. Perforations  63 V serve as selectable anchor points for hook  74  of a cross arm  71 , as shown in  FIGS. 1 and 2  and described above. 
         [0113]      FIGS. 28 and 29  illustrate another modification of handlebar strut  51 , in which the upper swivelable joint  92  thereof is replaced by an adjustable length joint  292  which may optionally be locked to prevent flexural motion of upper cylindrical bar section  53 C of the strut relative to intermediate tubular section  52 C of the strut. 
         [0114]    As shown in  FIGS. 28 and 29 , modified handlebar strut  51 C has an upper swivelable joint  292  which connects an upper end of an intermediate tubular section  52 C to an upper central bar section  53 C of the strut. Joint  292  is similar in construction and function to swivelable joint  92  which connects intermediate tubular section  52  and upper bar section  53  of the basic embodiment  51  of a handlebar strut, as illustrated in  FIG. 17  and described above. However, as shown in  FIGS. 28 and 29 , a longitudinally disposed end portion  53 E of cylindrical bar section  53 C is provided with external helical threads  53 F which are disposed axially inwardly from lower transverse end face  314  of the cylindrical bar section. A cylindrically-shaped collar  315  which has internal helical threads  316  fits threadingly over end portion  53 E of cylindrical bar section  53 C. With the outer transverse edge wall  317  of collar  315  threadingly retracted from transverse end wall  314  of tubular intermediate section  52 C of strut  51 C, upper cylindrical section  53 C may be locked or unlocked relative to the tubular intermediate section by rotating the collar  315  about the axis of an Allen bolt  304  which threadingly joins the upper and intermediate sections of the strut. When upper cylindrical bar section  53 C has been adjusted to a desired extension length relative to intermediate tubular section  52 C, collar  315  is threadingly advanced towards the central tubular section until outer (lower) transverse end wall  317  of the collar abuts outer (upper) transverse end wall  314  of the central tubular section. With joint  292  thus configured, central tubular section  52 C and upper cylindrical section  53 C of strut  51 C are axially aligned and locked against relative motion therebetween. 
         [0115]      FIGS. 30-32  illustrate a modification of cross-lock arm  71  shown in  FIGS. 7 ,  19 ,  20  and described above. A modified cross-lock arm  71 C shown in  FIGS. 30-32  is useful for securing a pair of motorcycles in a laterally spaced apart arrangement, as shown in  FIG. 6 . 
         [0116]    Referring to  FIGS. 30-32 , it may be seen that modified cross-lock arm  71 C includes an elongated hollow cylindrical tube  72 C which telescopically slidably receives within bore  73 C thereof an elongated cylindrical bar section  75 C. Cylindrical bar section  75 C is telescopically extendible a selectable distance from tubular section  72 C of cross-lock arm  71 C, and fixed at that distance by a cylindrical key lock  76 C, which protrudes radially outwards from an outer cylindrical wall surface  77 C of the tubular section, near lower transverse end  78 C thereof. 
         [0117]    As shown in  FIGS. 30 and 31 , cross-lock arm  71 C includes a U-bolt clamp assembly  79 C which is attached to lower transverse end  318  of cylindrical bar section  75 . U-bolt clamp assembly  79 C includes a saddle  319  which has a flat rectangular base  320  that is fastened concentrically to lower transverse end  318  of the cylindrical bar section. Saddle  319  has an outer transverse wall  321  in which is formed a generally semi-circularly-shaped longitudinally inwardly disposed concave notch  322  that is positioned midway between a pair of rectangularly-shaped side walls  323 L,  323 R which protrude perpendicularly outwards from base  320 . 
         [0118]    Base  320  of U-bolt clamp  79 C has disposed perpendicularly through its thickness dimension a pair of laterally spaced apart longitudinally disposed bores  324 ,  325  located short equal distances inwardly from side walls  323 L,  323 R, respectively. Bores  325 ,  324  receive the threaded and smooth, longitudinally disposed shanks  326 ,  327 , respectively, of a U-bolt  328 . Bore  324  for smooth U-bolt shank  327  preferably has a key-hole shaped extension  329  which protrudes radially outwardly from the inner circumferential wall surface  330  of the bore. Smooth shank  327  of U-bolt  328  is provided with a locking pin  331  which protrudes outwardly from outer cylindrical wall surface  332  of the shank, near outer transverse end  333  of the shank. Thus constructed, smooth shank is insertable into bore  324  of saddle  319 , with pin  331  aligned in parallel with key hole extension  329 , and prevented from withdrawal from the bore with the shank rotated 90 degrees, as shown in  FIG. 31 . 
         [0119]    As shown in  FIG. 31 , U-bolt clamp assembly  79 C has a generally circular or oval-shaped opening  334  formed between saddle notch  322  and a generally semi-circularly-shaped inner wall  335  of U-bolt  328 . Opening  334  is of an appropriate size and shape to receive therethrough either of the left and right front fork tubes FTL, FTR of a motorcycle, as shown in  FIG. 6 , whereupon U-bolt clamp assembly  79 C is secured to the fork tube by tightening a wing nut  336  on a threaded portion  326  of U-bolt shank which protrudes through bore  325 . As shown in  FIGS. 30 and 32 , cross-lock arm  71 C also includes a U-bolt clamp assembly  74 C which is attached to outer transverse end  338  of tube  72 C of the cross-lock arm. U-bolt clamp assembly  74 C is identical in structure and function to U-bolt clamp assembly  79 C. 
         [0120]      FIGS. 33 and 34  illustrate a handlebar locking arm  340  for use with the lockdown apparatus of  FIG. 1 . The purpose of handlebar locking arm  340  is to provide anchor eyes  341 ,  342  for engagement by J-hooks  54  of handlebar support struts  51 , when apparatus  50  is used to lockdown a street-type motorcycle which has short, downwardly angled handlebars which would not otherwise be readily engageable by J-hooks  54 , as may be understood by referring to  FIG. 35 . 
         [0121]    As shown in  FIG. 33 , handlebar locking arm  340  includes an L-shaped, circular cross-section hollow tubular beam  343  which has an upwardly disposed upright leg  344  and a longer, laterally inwardly disposed leg  345  which protrudes perpendicular inwardly from an upper elbow-shaped transition section  346  located at an upper end portion of the upwardly disposed leg. 
         [0122]    As is also shown in  FIG. 33 , handlebar locking arm  340  also has an L-shaped, circular cross-section cylindrical bar  353  which has a shape that is symmetrical to that of tubular beam  343 . Thus, bar  353  includes an upwardly disposed upright leg  354  and a longer, laterally inwardly disposed leg  355  which protrudes perpendicularly inwardly from an upper elbow-shaped transaction section  356  located at an upper end portion of the upwardly disposed leg. Lateral leg  355  of bar  353  is telescopically received within a coaxial bore  357  disposed laterally through leg  345  from inner transverse end wall  358  of the straight tubular leg. Leg  355  of bar  353  is secured at an adjustable extension length from straight tubular leg  345  by a pin  359  advanced into a selected one of a plurality of longitudinally spaced apart blind bores  360  which are formed in the outer cylindrical wall surface  361  of leg  355 , the pin being advanced by inserting a key into and turning the cylinder  362  of cylindrical lock  363  which protrudes radially outwards from outer cylindrical wall surface  364  of tubular lateral leg  345 . As shown in  FIGS. 33 and 34 , handlebar locking arm  340  includes a pair of tubular-shaped handlebar receiver cups  365 L,  365 R fastened to lower ends  367 ,  368  of upright tubular leg  344  and upright bar leg  354 , respectively. Tubular handlebar receiver cups  365 L,  365 R may be identical in structure and function, and include a longitudinally elongated, hollow cylindrical tube section  369  which has disposed longitudinally through its length a coaxial cylindrical bore  370 . Bore  370  is of the proper size to insertably receive in an opening  371  in an inner transverse end wall  372  thereof the handgrip end of a motorcycle handlebar. Tube section  369  of handlebar receiver cup  365  has located at a longitudinal end thereof opposite to that of inner transverse annular end wall  372  a circular disk-shaped outer end wall  373 . Outer end-wall  373  has protruding perpendicularly outwards from outer surface  374  thereof a U-shaped eye bolt  375 . Eye bolt  375  has a pair of parallel, radially apart legs  376 ,  377 , which join an arc-shaped outer section  378 , forming an oval-shaped eye  379  between end-wall outer surface  374  and arc-shaped portion  378 . 
         [0123]    As shown in  FIGS. 33 and 34 , each handlebar receiver cup  365  includes a hollow, cylindrically-shaped boss  380  which protrudes radially outwardly from outer cylindrical wall surface  381  of tubular section  369 . As shown in the Figures, boss  380  is positioned midway between inner transverse annular end wall  372  and outer transverse wall  373  of tubular handlebar receptacle cup section  369 . 
         [0124]    Boss  380  functions as a component of a swivelable joint  392  which swivelably joins handlebar receiver cups  365 L,  365 R to left and right uprights  343 ,  353  of handlebar locking arm  340 . In a preferred embodiment, swivelable joins  392  are similar in construction and function to swivelable joint  92  shown in  FIG. 11  and described above. 
         [0125]      FIG. 35  illustrates the manner of using handlebar locking arm  340 , in which left and right handlebar grips  74 L and  74 R are inserted into inner openings  371 L,  371 R of left and right handlebar receiver cups  365 L and  365 R, respectively. Tubular beam  343  and bar  353  are then telescopically collapsed relative to one another to decrease lateral opening between left and right handlebar receiver cups  365 L and  365 R, and key lock  363  operated to secure the uprights  344  and  354  at a lateral spacing which secures handlebar cups HR and HL with their respective handlebar receiver cups. J-hooks  54  of a pair of handlebar support struts  51  are then hooked into openings  379 L and  379 R of eye bolts  375 L and  375 R, and the struts secured to an anchor member as shown in  FIGS. 1 and 34 .