A chair-shaped hoverboard attachment may comprise at least one chair atop a platform having at least one wheel on the platform's underside, wherein the platform contains a control box and a removable hoverboard attachment element, such as a strap. In some embodiments, one or more control rods with brake controls may extend from the platform to within reach of the chair and may be configured to control the hoverboard.

A walker-shaped hoverboard attachment provides a center platform having a cavity and a rim around the cavity configured to rest on either side of a hoverboard's upper surface. Support rails and crossbars collectively configured as a walker may be fixedly connected to the platform. One or more brakes on one or more grips may enable a user to control the hoverboard while a user is standing on the platform.

Various embodiments of side-by-side flexible adjacent vehicles, such as twin bikes, are disclosed including includes two vehicles joined together side-by-side by means of a plurality of interconnecting pivoted link bars. One or more driver riders may simultaneously or independently operate said side-by-side flexible adjacent vehicles. The side-by-side flexible twin bicycle may be configured employing different size bicycles, in-line multi-rider tandem bicycles, recumbent bicycles, mountain bicycles, and motorcycles of various types. These embodiments provide the vertical stability of a four-wheel vehicle while retaining the ability to lean into turns and ride over irregular surfaces affording for each of the riders the handling, ride and feel similar to that of a single conventional vehicles.

Various embodiments of side-by-side flexible adjacent vehicles, such as twin bikes, are disclosed including includes two vehicles joined together side-by-side by means of a plurality of interconnecting pivoted link bars. One or more driver riders may simultaneously or independently operate said side-by-side flexible adjacent vehicles. The side-by-side flexible twin bicycle may be configured employing different size bicycles, in-line multi-rider tandem bicycles, recumbent bicycles, mountain bicycles, and motorcycles of various types. These embodiments provide the vertical stability of a four-wheel vehicle while retaining the ability to lean into turns and ride over irregular surfaces affording for each of the riders the handling, ride and feel similar to that of a single conventional vehicles.

The kit for pairing two bicycles includes a rear angle member, a seat-to-seat tube member, a pair of head-to-head tube members, and a tie-bar. The rear angle is adapted to attach between chain stays of a first bicycle and a second bicycle. The seat-to-seat tube member is adapted to attach to seat posts of the first bicycle and the second bicycle. The pair of head-to-head tube members is adapted to extend between the head tubes of the first bicycle and the second bicycle. The tie-bar is adapted to attach to a fork of the first bicycle and the second bicycle in order to provide consistent steering when in use. When installed, the kit securely aligns the first bicycle parallel with the second bicycle such that both bicycles ride and move in unison.

The kit for pairing two bicycles includes a rear angle member, a seat-to-seat tube member, a pair of head-to-head tube members, and a tie-bar. The rear angle is adapted to attach between chain stays of a first bicycle and a second bicycle. The seat-to-seat tube member is adapted to attach to seat posts of the first bicycle and the second bicycle. The pair of head-to-head tube members is adapted to extend between the head tubes of the first bicycle and the second bicycle. The tie-bar is adapted to attach to a fork of the first bicycle and the second bicycle in order to provide consistent steering when in use. When installed, the kit securely aligns the first bicycle parallel with the second bicycle such that both bicycles ride and move in unison.

An adjustment device usable on equipment such as sports equipment for children or as a pram, pushchair, stroller or similar device to adjust the spacing between wheels of such equipment. The adjustment device includes at least one slider body comprising a curved guide track disposed on the body of the equipment mirror-symmetrically to the longitudinal principal plane of the at each side of said longitudinal principal plane, the slider body comprises a sliding member that is configured to correspond in size and shape to the curved guide track of the slider body, and can be displaced along the curved guide track of the slider body, with the curved movement paths of the sliding members and the centrelines of the guide tracks of the slider body constituting mutually corresponding circular arcs.

An adjustment device usable on equipment such as sports equipment for children or as a pram, pushchair, stroller or similar device to adjust the spacing between wheels of such equipment. The adjustment device includes at least one slider body comprising a curved guide track disposed on the body of the equipment mirror-symmetrically to the longitudinal principal plane of the at each side of said longitudinal principal plane, the slider body comprises a sliding member that is configured to correspond in size and shape to the curved guide track of the slider body, and can be displaced along the curved guide track of the slider body, with the curved movement paths of the sliding members and the centrelines of the guide tracks of the slider body constituting mutually corresponding circular arcs.

A kit for an electric cycle includes a powertrain module including a case, a battery disposed in the case, an electric motor in communication with the battery and disposed in the case, and a connecting port on the case. The kit includes a first module including a frame member configured to releasably engage the connecting port and a wheel rotatably connected to the frame member, a second module including a frame member configured to releasably engage the connecting port, and a releasable locking feature on the connecting port.

A kit for an electric cycle includes a powertrain module including a case, a battery disposed in the case, an electric motor in communication with the battery and disposed in the case, and a connecting port on the case. The kit includes a first module including a frame member configured to releasably engage the connecting port and a wheel rotatably connected to the frame member, a second module including a frame member configured to releasably engage the connecting port, and a releasable locking feature on the connecting port.