Abstract: A laser measuring device which comprises a horizontal rail, a vertical pole slidable on the horizontal rail, a laser source mounted on the vertical pole for sliding movement in the longitudinal direction of the vertical pole, a ferromagnetic web provided on each of the horizontal rail and the vertical pole and extending in the longitudinal direction of the horizontal rail or the vertical pole, respectively, a self-retractable tape measure provided on each of the horizontal rail and the vertical pole and extractable in the longitudinal direction, a paramagnetic member attached to the leading end of each tape measure; and an engaging member provided on the leading end of each tape measure and engageable with the base portion of the vertical pole or the mounting base of the laser source.

Abstract: A vehicle alignment system uses transverse, longitudinal and vertical bars mounted on a vehicle and equating to X, Y and Z axes for establishing the dimensions of the vehicle, which dimensions are then compared to the vehicle engineering specifications. The transverse bars are connected to the underside of the vehicle and, to enable quickness and ease of transferring the alignment system between vehicles, quick connect fittings extend between the transverse and longitudinal bars. Additional supports extend between the longitudinal bars and a base surface. The system is arranged so that transverse bars in a path of entry and exit of the vehicle can be readily removed and the vehicle removed and replaced, while maintaining the alignment system substantially set up and ready for use. The process improves the speed of use of the system by substantially alleviating the dismantling previously required.

Abstract: The invention relates to an arrangement for measuring wheel alignment and steering geometry in an automobile. A substantially horizontal bar is placed in front of the vehicle at right angles to its longitudinal axis. A light source displaceable along the bar emits a narrow ray of light at an angle to the bar. The vehicle front wheel to be measured is provided with a unit including at least three angle sensors of which at least one comprises a widely dimensioned light detector placed in the focal plane of an optical means. The light source on the bar is set to a position on said bar where the emitted light beam strikes the optics approximately at the center thereof. A calculating device determines the wheel alignment values with the aid of the angle sensor signals for variable positions of the wheel and the motion of the light source along the bar.

Abstract: An improved measuring bar device includes first and second parallel bars retained in a center housing by an array of biased and canted rollers that engage cam surfaces defined by the bars to provide for equal and opposite movement of the bars while maintaining the bars in parallel array.

Abstract: A frame straightening and measuring system for auto body repair is provided including position locating arms moveable along each of three axis, each of said arms being provided with an extendable retractable measuring device such as a roll-up type tape measure provided with means for clamping the free end thereof at a desired location on the extendable position locating bars whereby the correct position of a damaged part relative to the axis of the motor vehicle can be determined accurately.

Abstract: A method and apparatus for determining or adjusting a projecting direction of a light beam emitted from an automobile headlight is provided. In a first aspect of the present invention, the peripheral region of a light beam is used in determining its projecting direction. In particular, a region definable in a light pattern of the projected beam having a proportionality relation between log S and I, where S indicates the value of an area having light intensity I or above, is determined and its outer contour or any predetermined point in the contour is used in determining the projecting direction. In a second aspect, apparatus for determining a projecting direction of a light beam emitted from an automobile headlight includes an indicator which automatically indicates a predetermined position of a light pattern of the light beam projected.

Abstract: Automatic measurement of toe setting, thrust angle and run-out compensation provide data for automatic adjustment of the toe planes of front wheels of a motor vehicle. Vehicle stabilizers are employed for moving the vehicle so that the center line of the vehicle is coincident with the center line of the toe-set alignment system. Transducer units derive static toe angles and camber, as well as dynamic run-out compensation values for all from wheels of the vehicle.

Abstract: A vehicle alignment system uses transverse, longitudinal and vertical bars mounted on a vehicle and equating to X, Y and Z axes for establishing the dimensions of the vehicle, which dimensions are then compared to the vehicle engineering specifications. The transverse bars are connected to the underside of the vehicle and, to enable quickness and ease of transferring the alignment system between vehicles, quick connect fittings extend between the transverse and longitudinal bars. Additional supports extend between the longitudinal bars and a base surface. The system is arranged so that transverse bars in a path of entry and exit of the vehicle can be readily removed and the vehicle removed and replaced, while maintaining the alignment system substantially set up and ready for use. The process improves the speed of use of the system by substantially alleviating the dismantling previously required.

Abstract: A hole gauge arrangement is used for determining the distance of a vehicle fixture hole from a datum plane established with respect to the vehicle. The hole gauge arrangement includes a set rod with a die wheel having bores corresponding to the various sizes of fixture holes and also includes a measurement rod. By reference to a table, the desired distance from the datum plane to the fixture hole is established on the set rod and the measurement rod matched to the distance of the set rod and the hole diameter. The measurement rod is then transferred to support structure mounted in the datum plane and the distance difference, if any, between the measurement rod tip and the fixture hole is noted as an indication of dislocation.

Abstract: The present invention relates to a laser gauging apparatus for measuring a vehicle during the construction of and the repair of the vehicle. The apparatus includes a T-shaped rail arrangement. On one of the rails, a laser carriage is mounted which carries a laser along the rail. Laser measuring instruments are mounted on the other rail. The laser gauging apparatus projects a beam having a horizontally extending portion and a vertically extending portion. The horizontally extending portion defines a horizontal datum plane under the vehicle from which measurements can be taken to the vehicle to determine the correct position of datum points on the vehicle. In accordance with the present invention there is also provided a laser target which can be suspended from the datum vehicle point. The target when suspended and when intersecting the laser beam, indicates that the vehicle reference datum point is in proper position.

Abstract: Vehicle wheel alignment apparatus having preferred constructions in which the angle measuring components are assembled at each wheel in a unique cooperative arrangement and in which certain of the components represent existing wheel positions and other components relate the wheels in pairs so important alignment characteristics may be investigated for all wheels as well as the steerable wheels in relation to the non-steerable wheels.

Abstract: The present invention discloses an apparatus for the measurement of the underframe of a motor vehicle. The apparatus takes the form of a pair of "roof racks" able to be suspended underneath the vehicle by the door sills. A longitudinal arm carrying a pointer is able to be radially swung about a central pivot point and/or slid from side to side to enable comparison measurements of corresponding left and right side portions of the vehicle to be taken.

Abstract: Apparatus is provided for determining the relationship between a vehicle's thrust line and the vehicle's body center line. A movable light source is located externally of and independent of the vehicle and serves to establish a pair of reference light beams falling in parallel planes and which are spaced apart sufficient to permit a vehicle to be positioned longitudinally therebetween. The vehicle's thrust direction is determined by mounting sensors on the nonsteerable wheels so as to extend transversely away from the vehicle's body to intercept the light beams, together with circuitry for providing output indications dependent upon the location of light interception and which indications are representative of the vehicle thrust direction. The body center line is determined by employing targets which are mounted to body sides of the vehicle to intercept reference light beams.

Abstract: An elongated vertically disposed shank construction is provided defining a longitudinal center axis and the upper end of the shank construction includes structural features enabling the shank construction upper end to be anchored relative to a vehicle frame portion having a vertical bore formed therethrough with the longitudinal center axis of the shank construction coinciding with a selected edge portion of the bore. Further, the lower end of the shank construction includes location determining structure disposed on the longitudinal center axis of the shank construction, whereby frame measurement locations determined by specified margin edges of vertical bores formed in the vehicle frame may be established at an elevation spaced below the frame.

Abstract: This invention is a means for indicating the alignment or non-alignment of vehicle type frames. The device clips over a portion of the frame with an indicator arm terminating in an indicator finger which, if in alignment, will point toward a pre-determined location on the frame. If the frame is not in alignment, this is also readily apparent by the indicator being off the pre-determined location.

Abstract: A vehicle measuring instrument to measure a position-deviation of any selected vehicle reference point as when a person such as a car mechanic performs repair and maintenance of a car. With the well known vehicle measuring instrument of such type, an error caused by a deviation of the perpendicularity indicated by a pendulum member from the vertical direction of the vehicle due to an inclination of this vehicle has been detected and then a troublesome sequence of operations have been performed to compensate such error. According to the present invention, there is provided an angle variable portion by which an angle of each suspender with respect to a base frame can vary under an effect of this base frame's own weight in response to an inclination of the vehicle so that a reference portion is automatically displaced so as to respond to the deviation of the pendulum member and thereby to compensate said error automatically.

Abstract: An apparatus and method for determining the proper position of misaligned vehicle parts utilizes an X, Y and Z coordinate system to provide a proper point of position, or alignment, of vehicle parts which are identified in tables by such coordinates. The apparatus includes a framework which is established about the vehicle by transverse bars, datum plane bars, cross bars and a vertical standard, all with scale indicia, and forming a point of origin as on a graph. Lasers emitting planes of visible light are mounted on the datum plane bars and cross bar and project mutually perpendicular, intersecting planes of light. A laser is also mounted on the standard to project a horizontal plane of light that intersects the other two light planes and establishes a point capable of definition by X, Y and Z coordinates.

Abstract: A wheel alignment system uses head units attached to each of the four wheels. The front head units contain photodetector arrays which view across the front of the vehicle and to the rear. The rear units carry photodetector arrays which look forward. Each photodetector array views a target on one of the other head units. A microcomputer in each head unit determines an angular value based upon the position of the target image on the photodetector array. The angle values determined by the microcomputers of the individual head units are supplied to a master computer in a main console which determines individual toe angles with respect to a tread centerline for either the front two wheels or for all four wheels. The master computer controls a display at the main console, as well as a remote display to guide the mechanic in making alignment adjustments.

Abstract: A selectible beam/plane projecting laser is particularly useful for vehicle frame and body alignment. A lens contained in a holder mechanism mounted on a laser projector housing flips into and out of the laser beam path and when in the path, changes the beam to a plane. When used for vehicle frame and body alignment, the plane of the laser generated light allows the operator to spot targets any place in the plane of light and makes easier determination of alignment conditions.

Abstract: A wheel alignment and ball joint wear monitoring system employs a diagrammatic pictorial video display of the chassis of the vehicle being aligned and pictorial diagrams of alignment parameters associated with each of the wheels of the chassis. The region of each wheel when separately enlarged carries a chassis diagram indicating which wheel portion of the diagram has been enlarged. The system permits successive measurements of camber and of toe to be used to determine ball joint wear in the vertical and horizontal planes.

Abstract: A connector for mounting a vehicle measuring system to a vehicle fixture hole includes spaced arms with projecting end lugs which evenly and symmetrically open and grip the material defining the hole so that the connector is centered with respect to the hole. Rotation of a thumb wheel operates a wedge arrangement to evenly spread the arms and securely tighten the connector to the material defining the hole. A bushing on the connector is connectible to the vechicle measuring system and is longitudinally adjustable to set a precise distance from the measuring system to the fixture hole.

Abstract: An arrangement for mounting measuring devices of axle measurement equipment with a fastening plate that is adapted to be installed at the vehicle wheel aligned parallel to a flat reference surface of the vehicle axle by means of abutment pins extending through the wheel disk by way of through-openings. An incorrect alignment of the plane of the fastening plate which causes an incorrect adjustment of camber, toe-in or caster, is avoided with a completely satisfactory abutment of all abutment pins at the reference surface.

Abstract: Apparatus and a method for aligning the rolling plane of each of the wheels of a car, truck, trailer or other wheeled vehicle to factory specifications and to be parallel to the thrust line of the rearmost wheels. The apparatus comprises various embodiments of an adjustable stationary reference "halo", mountable in concentric relation about a vehicle or trailer, and relative to which individual gauge assemblies mounted to each of the wheels detects each wheel's toe condition and permits the determination of the vehicle or trailer thrust line and the correction of the rear suspension thereto. Wheel mountable caster, camber and king-pin inclination/strut angle detecting assemblies, in turn, permit the detection of each of these respective conditions for each wheel and the correction of each condition in relation to the established thrust line.

Abstract: An improved vehicle frame alignment gauge. The gauge can be readily installed and operated by a single mechanic. The gauge does not have to be attached to and suspended from a vehicle frame and does not have to be readjusted while the frame is being stressed to alter the shape of the frame.

Abstract: Measuring apparatus for use in vehicle collision repair work. The measuring apparatus comprises first and second telescopic extension members each having a first end for affixation, respectively, at first and second reference points. A cross-member is connectible between the second ends of the extension members. Indicator means are provided on each extension member for indicating displacement between the extension member first and second ends. Alignment means are also provided for aligning the extension member second ends on opposite sides of the vehicle center line and at equal distances from that center line. Third and fourth indicator means are also provided for indicating, respectively, the vertical height of third and fourth reference points above a reference line defined by the extension member second ends. The third and fourth indicator means also indicate, respectively, horizontal displacement of the third and fourth reference points from the vehicle center line.

Abstract: A device for locating a wheel and tire rim assembly on a right angular plane to the axis of a vehicle's axle by aligning the optical projection from a light source supported on the wheel or tire rim assembly to a remote target with a movable indicator positioned thereon.

Abstract: Disclosed is a method and apparatus for measuring deviations in vehicle bodies or frames in connection with inspection of damage or alignment of deformed vehicles. The measuring apparatus comprises gripping means which are attached to reference points on either side of the vehicle, transverse beams having graduated scales thereon, a center beam, a measuring beam and at least one measuring rod for direct or cross measurement. The device is relatively light weight and compact, and the beams are provided with quick couple attachments so that the measurement can be performed in a relatively short time period.

Abstract: An improved method, and apparatus for performing the method, is disclosed for measuring and correcting the individual toe of pairs of steerable and non-steerable wheels of a vehicle relative to a longitudinal centerline passing through the midpoints of the wheel pairs. The improved methods utilize aimable alignment heads which are alternately mounted on the non-steerable wheels and the steerable wheels and are sighted only once on targets on the other wheels thereby eliminating the need for resighting after each toe adjustment is made. Optical cross-toe paths of each head operate in a continuous mode and provide a running display of incremental toe angle adjustments of one wheel while the toe display value associated with the other wheel of the pair is frozen, which other wheel is not being adjusted for toe.

Abstract: A measuring bridge for determining the degree of motor vehicle damage includes a main frame which defines a reference plane and has a plurality of locating holes formed therein. Vehicle support means is mounted on the main frame in a predetermined relation to the locating holes for supporting a vehicle on the main frame with datum points beneath the vehicle being in a predetermined orientation relative to the locating holes. A first measuring gauge includes an elongate bar affixed to the locating holes and oriented below and in parallelism with the vehicle's center line and slide means mounted for longitudinal movement on the elongate bar. Slideably mounted on the slide means for transverse movement perpendicular to a plane containing the axis of the first elongate bar is an elongate measuring element.

Abstract: An elongated wheeled bench is provided for predetermined aligned positioning beneath a stationary jack stand supported vehicle body to be straightened and includes, supported therefrom at one end, a vertically adjustable horizontally elongated mount extending transversely of the bench. The mount has a light beam generating head mounted thereon for adjustable positioning therealong and also for angular displacement relative thereto about a first axis paralleling the mount and a second axis disposed normal to the first axis. The head is operable to generate a narrow light beam disposed normal to the second axis and scales are provided to indicate angular positioning of the head about the first and second axes and also longitudinal positioning of the head along the mount.

Abstract: Motor vehicle wheel alignment measuring apparatus, which enables measurement of toe-in, lateral offset and out of square conditions with respect to any given set of tires, comprises pairs of frames adapted to be hung by hooks against the side walls of the exposed tires of a set of tires. A combination of spring and elastic members are provided for engaging the frames with tire sidewalls. Methods include measuring the toe-in of a set of tires, the alignment of all the tires, and vehicle bearing wear, all while the tires are supporting the vehicle.

Abstract: A self-centering alignment gauge for determining automotive frame and body structure alignment has a clip to permit hanging such gauges outside of the vehicle body, from the top surface of the rocker panel.

Abstract: An apparatus and method is disclosed which utilizes modified wheel aligner heads and which accomplishes measurement of individual wheel toe on a vehicle having a pair of non-steerable rear wheels and a pair of steerable front wheels. The apparatus and method provides measurement of a steering or a rolling direction for the front and the rear wheel pair as a result of optical measurements taken relating the orientation of the planes of the wheels to the centerline of the vehicle chassis. Once the steering direction of the front wheels is obtained, individual toe measurements for the front wheels may be made relative to the chassis centerline. Alternatively, once the steering or average rolling direction of the rear wheels is obtained individual toe measurements for the rear wheels may be made relative to the chassis centerline and individual toe measurements for the front wheels may be made relative to the rear wheel rolling direction.

Abstract: The device for checking the positions of shock-absorber heads of a McPherson suspension system comprises a horizontal cross-beam which is placed above the front end of a damaged or undamaged vehicle body to be checked and which is pivotally mounted on two lateral support brackets. Two sliders mounted on the cross-beam each carry a pivoted control arm, the lower end of which is placed opposite to the center of the corresponding shock-absorber head. Graduated scales placed above each slider and on each control arm provide a direct visual indication of forward or backward angular displacement of the cross-beam with respect to the lateral support brackets and of outward or inward inclination of the control arms of the sliders.

Abstract: The target includes an L-shaped member in which the short leg defines a fixed jaw. A second jaw is slidably mounted on the long arm of the member, which jaw is associated with latching means so that the two jaws can engage against the opposite side walls of a tire and be retained thereby. A second arm is spaced from and attached to the first arm and slidably carries a scale.

Abstract: A vehicle frame measuring and aligning apparatus comprises parallel rails with transverse reference members moveable along the longitudinal axis of the rails slideable vertical locating members are mounted on the rails. The apparatus also comprises an overhead measuring and alignment device which is slideably attached to the rails, with a vertically adjustable overhead bar to which referencing and measuring members attach. Clamping devices are used to secure the vehicle in place.

Abstract: A wheel alignment measuring apparatus including four angle measuring instruments for mounting on front wheels and rear wheels of a vehicle, and including a calculation circuit for the determination of track measuring values. A measuring bridge is operatively provided essentially transversely to the driving direction and is positioned approximately between the front wheels and the rear wheels. Four additional angle measuring instruments are provided, two being operatively arranged on one side and two being operatively arranged on the other side of the measuring bridge. An elastic tension member is operatively connected between the four angle measuring instruments and the four additional angle measuring instruments for measuring the angle positions of the wheels. The calculation circuit determines the track measuring values from comparing angular positions of all angle measuring instruments.

Abstract: A measuring bridge for determining the degree of motor vehicle damages includes a main frame and a plurality of vehicle supports adjustable three dimensionally relative to the main frame. A first elongate guage is pivotally connected to a magnet coupler securable to the frame and having a pair of longitudinally and vertically adjustable measuring elements for the successive location of a plurality of datum points on the bottom of the vehicle. In addition, a plurality of tram gauges are supported on the main frame above the vehicle and are adjustable three dimensionally for locating datum points located on upper portions of the vehicle.

Abstract: A dimension measuring apparatus, for automatically measuring a dimension of a workpiece as the workpiece is on a production line, has a probe with a tapered end for insertion into a hole of the workpiece to be measured. The probe is supported by a second movable base provided on a first movable base. The first movable base is slidably provided on a frame member in one direction in a planar level and the second movable base is slidably provided on a grooved upper surface of the first movable base in another direction perpendicular to the one direction in the planar level. The movement value of the probe is detected by means of detecting the movement values of the first and second movable bases through potentiometers.

Abstract: There is disclosed herein a gauge for aligning opposite points within opposite surfaces of a normally symmetric body. The gauge comprises an elongated guidebar disposed above and upon the symmetric body. The guidebar is also perpendicularly transverse to the plane of symmetry of the symmetric body. Also included are left and right calibration assemblies which are slideably disposed upon and within opposite halves of the guidebar, each of the calibration assemblies themselves include an X- and Y-axis joystick connected, in each axis, to respective means for converting linear physical displacement of the joystick to corresponding electrical output signals.

Abstract: A laser alignment system for vehicles includes a laser module for attachment to either the front or rear wheels of a vehicle, a sensor module for attachment to the other wheels of the vehicle, and a control module connected to the laser module and the sensor module. Both the laser module and the sensor module can be attached to wheel spindles by the use of magnets, thereby eliminating rim adaptors and speeding set-up time. The modules are movable relative to the spindles and to each other so as to correct for vehicle uneveness, frame damage, and non-level floors. An electro-mechanical pendulum included as part of the sensor module provides fast, accurate caster and camber readings on a continuous basis for each wheel. The sensor module provides continuous, optical readouts of toe-in and toe-out for each wheel.

Abstract: The alignment of the front and rear wheel systems of automotive vehicles as well as the dynamic setback and static setback are measured by means of an angular displacement pickup supported by a horizontal arm at the level of each front wheel and connected by a reference straight line to the opposite pickup. A light beam produced by an emitter carried by each arm is reflected from a mirror carried by the rear wheel and impinges on a photosensitive cell. Wheel alignment and setback angles are obtained from the angle values determined by the pickups and corresponding to direction-changing movements of the front wheel system which is turned successively from left to right and from right to left.

Abstract: An adjustable carriage for mounting a measurement bar to a selected vehicle frame or body having locations corresponding to measurement points utilizes a carriage block sleeved about and slidably embracing the bar and has a clamp to secure the block at a selected location. An adjustable arm is mounted on the carriage block and has a socket affixing connectors which mount the bar from the vehicle. The arm is shiftable angularly to enable connection to the body at the proper points even though the points may be coarsely misaligned or deformed through damage.

Abstract: Reversible universal stand for inspection and repairing damaged motor vehicles comprising: a solid caisson-shaped frame, a square mesh modular drilling made directly on the longitudinal flanks and at least one main side of the frame. A system of squares-brackets having multiple functions and avoiding particularly the use of cross bars, various accessories: shoes, "cage"-shaped nut magnetic counter plates, etc., an original measuring device, using the modular drilling of the stand, and comprised of one or a plurality of independent units comprising: a squared projection plate, a weighted extensible measuring rod, a hooking device for hooking at the controlled point.

Abstract: A wheel alignment process using manually operable alignment apparatus wherein all four wheels of a vehicle having a front steerable wheel pair and a rear nonsteerable wheel pair may be set in toe without turning the vehicle around part way through the process. The process provides for setting both front and rear toe relative to the chassis centerline in one aspect of the disclosure and for setting rear toe as close as practical to the chassis centerline and the front toe relative to the rear wheel rolling direction in another aspect of the disclosure. A lock is also disclosed which assures stability of the reference for the front and rear toe settings during the practice of the toe setting process.

Abstract: A vehicle frame measuring and aligning apparatus comprises parallel rails with transverse reference members moveable along the longitudinal axis of the rails slideable vertical locating members are mounted on the rails. The apparatus also comprises an overhead measuring and alignment device which is slideably attached to the rails, with a vertically adjustable overhead bar to which referencing and measuring members attach. Clamping devices are used to secure the vehicle in place.

Abstract: In a disclosed practice, the method comprises pendently attaching translucent sighting targets to a plurality of at least three vehicle frame datum points, at distances, standardly-prescribed for the particular vehicle, from the latter's reference line (or one of such reference lines), and taking a linear sighting, with a coherent light beam, through the targets to ascertain alignment and misalignment, if any of the latter, of any one of the targets relative to at least two others thereof. The novel means, in a disclosed embodiment thereof, comprises a plurality of sighting targets and hangers for pendently attaching the targets to vehicle frame datum points, and a laser gun for directing a laser beam along the targets to determine alignment and misalignment of any one of the targets relative to to two others thereof.

Abstract: The invention relates to measuring apparatus and its use, primarily for checking vehicle wheels, and more specifically the alignment of the rotational axes thereof. Two wheels, opposite each other on a vehicle, are provided with projecting stub axles which are disposed accurately coaxial with the respective wheel. The measuring apparatus comprises a scale unit (40) which is mounted on the axle of one of the wheels by means of a locating and fastening means (46, 48) so as to project at right angles therefrom and carrying a movable rider (50) with a scale (55), and a light beam unit (60) preferably comprising a laser (65) and disposed for mounting on the axle of the other wheel, by means of a locating and fastening means (66, 67), to send a light beam (33) onto the scale (55) carried by the movable rider (50) which is locked in an initial position.

Abstract: This apparatus comprises, in combination, two similar devices disposed in opposite directions. The devices are adapted to be fixed respectively to the two opposite wheels of a vehicle and parallel to the latter. Each device comprises a first rigid hollow tubular bar and a fixing structure for fixing the bar to a projector carrier. A structure inside the bar projects a beam of light longitudinally inside the bar. The beam is reflected at one end of the bar by a mirror which is rigid with a screen and so disposed as to project the beam transversely toward the screen pertaining to the opposite device. The mirror is mounted on the first bar of at least one of the devices so as to be movable toward or away from the fixing structure. A structure for receiving a sub-assembly for inspecting the pivot and castor angles of the vehicle wheel is provided. An apparatus for measuring the camber angle of the vehicle wheel is also provided.

Abstract: According to the invention an arrangement (10) is proposed for measuring and checking motorcycle frames, comprising a measuring beam (14) which is attached to one side of the motorcycle frame which is to be checked, parallel thereto and preferably at the so-called pivot-point of the frame. One or more uprights (16, 18) at right-angles to the beam (14) can be moved along the beam and themselves bear movable mountings (24, 28) with adjustable measuring points (26, 30). The latter can be made to seek out desired points on the frame, and with the aid of appropriate scales or calibrations the co-ordinates of the points relative to the pivot point can be determined. Two such measuring arrangements (10) placed one on each side of the motorcycle frame can be connected together by means of transverse bridges or the like to form a stable measuring stand.