A bicycle frame includes a top tube that connects to a head tube at a front portion of the bicycle frame. The bicycle frame also includes a first seat stay that connects to the top tube at a first point of intersection and a second seat stay that connects to the top tube at a second point of intersection such that a back portion of the top tube extends beyond the first point of intersection and the second point of intersection so that the top tube is a cantilever. The bicycle frame also includes a seatmast sized to receive a seatpost. The seatmast extends from the back portion of the top tube that forms the cantilever.

A bicycle comprising a frame; a handlebar assembly attached to an upper steering tube of the frame in such a way that at least the relative rotation between the two with respect to an upper axis is allowed, but the relative displacements between both in the directions perpendicular to the upper axis are restricted; a fork attached to a lower steering tube of the frame so that it has the same degrees of freedom relative to the lower axis between the fork and the lower steering tube as the degrees of freedom relative to the upper axis between the handlebar assembly and the upper steering tube; and a means for rotation transmission for transmitting at least partially a rotation of the handlebar assembly with respect to the upper tube into a rotation of the fork with respect to the lower steering tube.

This invention relates to polygonal frame structures made from anisotropic materials, and methods for their construction. The polygonal frame structures include at least one frame member that is constructed as a torsion box. The torsion box is constructed with layers of anisotropic materials, resulting in a lightweight, torsionally stiff polygonal frame. Natural and/or man-made anisotropic materials may be used. Wood may be used as a natural anisotropic material. The invention is applicable to bicycles and other vehicles, as well as other products, where frame structures having light weight and torsional stiffness are advantageous.

This invention relates to polygonal frame structures made from anisotropic materials, and methods for their construction. The polygonal frame structures include at least one frame member that is constructed as a torsion box. The torsion box is constructed with layers of anisotropic materials, resulting in a lightweight, torsionally stiff polygonal frame. Natural and/or man-made anisotropic materials may be used. Wood may be used as a natural anisotropic material. The invention is applicable to bicycles and other vehicles, as well as other products, where frame structures having light weight and torsional stiffness are advantageous.

A vehicle may have a seat and front wheel similar to those of a bicycle. However, the vehicle may have two rear wheels. The position of the two rear wheels may be adjustable. When the two rear wheels touch each other, the vehicle may function as a bicycle. When they are moved apart, the vehicle may function as a tricycle. In tricycle mode, the vehicle may travel autonomously without a human rider. In bicycle mode, a human may ride the vehicle like a bicycle. To transition between bicycle and tricycle modes, each rear wheel may rotate about a horizontal axis that is parallel to a longitudinal axis of the vehicle. In some cases, a bike chain is connected to only one of the rear wheels. In bicycle mode, motion imparted by the chain to one rear wheel may be transferred to the other by friction.

A bicycle frame set includes a front fork, a head tube, a main tube, a seat tube, and a seat stay. The front fork includes a right fork leg and a left fork leg. The front fork is rotatably coupled to the head tube. The main tube is connected to the head tube. The seat tube is connected to the main tube, the seat tube being configured to connect to a seat post. The seat stay includes a first portion connected to the seat tube at a front end of the first portion of the seat stay. When a rear wheel and a front wheel are mounted to the bicycle frame set, the first portion of the seat stay extends in a horizontal direction substantially parallel with respect to a ground plane supporting the rear wheel and the front wheel.

A bicycle frame set includes a front fork, a head tube, a main tube, a seat tube, and a seat stay. The front fork includes a right fork leg and a left fork leg, the right fork leg being substantially parallel to the left fork leg. The front fork is rotatably coupled to the head tube. The main tube is connected to the head tube. The seat tube is connected to the main tube, the seat tube being configured to be connected to a seat post. The seat stay is extending from the seat tube.

A fan powered folding wing bicycle apparatus for novelty and transportation includes a frame and a rear wheel coupled between a pair of lower horizontal tubes. A stem is pivotably coupled within a head tube. A handle bar is coupled to the stem. A pair of forks is coupled to the stem and a front wheel is coupled to the pair of forks. A pair of engine straps is coupled between a pair of top horizontal tubes. A duct is coupled to the pair of engine straps and a turbine is coupled within the duct. A seat is coupled to the duct. A battery is in operational communication with the turbine. A pair of wings is pivotably coupled to the pair of top horizontal tubes.

A fan powered folding wing bicycle apparatus for novelty and transportation includes a frame and a rear wheel coupled between a pair of lower horizontal tubes. A stem is pivotably coupled within a head tube. A handle bar is coupled to the stem. A pair of forks is coupled to the stem and a front wheel is coupled to the pair of forks. A pair of engine straps is coupled between a pair of top horizontal tubes. A duct is coupled to the pair of engine straps and a turbine is coupled within the duct. A seat is coupled to the duct. A battery is in operational communication with the turbine. A pair of wings is pivotably coupled to the pair of top horizontal tubes.

A bicycle has a front fork, within which the front wheel is mounted, attached to the head tube. Extending downwardly from each end of a lateral member are downwardly projecting forks, each comprising a primary portion, the respective primary portions extending downwardly and substantially parallel to each other. The longitudinal axes of both the main portion and a rider's lower leg are aligned. By aligning the wakes created by the forks and the lower leg a reduction in overall system drag is provided. Additionally or alternatively, the rear wheel may be provided between downwardly projecting stays, each comprising a primary portion, the respective primary portions extending downwardly and substantially parallel to each other. By aligning the downwardly projecting stays with the lower leg beneficial drag reduction is achieved.