Abstract: In a free-wheel for bicycles comprising an inner body integral with the wheel hub and an outer body carrying the chain drive sprockets, rolling on the inner body through two sets of balls, the seat for one of the sets is formed between a shoulder of the inner body and an adjustment cone screwed on the inner body. The cone is engaged with the shoulder through opposite conical centering surfaces, formed on the adjusting head of the cone and directly on the shoulder.

Abstract: A light and strong tube structure for frames of bicycles and motorcycles has its cross sections with a variable thickness of the tube wall. Said wall is formed by two or more layers of different materials, of which at least one is metallic material and at least another one has a preferential direction of tensile strength. Preferably, the straight cross sections of the tube are outwardly defined by a circle and inwardly defined by an ellipse and the said layers comprise an external metallic layer and an internal layer of fibers incorporated into resin.

Abstract: Freewheel device being formed by elements made of superlight material treated with a hard chromium plating, in which: the smallest sprocket wheel of the freewheel has a diameter almost equal to that of the inner body of the device onto the end of which it is fitted, and said end comprises two or more notches to be engaged by a control spanner, said notches extending axially in a very pronounced manner--the adjustment is carried out by means of a single spacer--the spring controlling the pawl of the freewheel consists of a steel wire engaging said pawl in the manner of a leaf spring.

Abstract: A fixture for mounting sprocket wheels on and removing them from the free-wheel units of bicycles, comprising a first tool in the form of an elongated metal plate, having a handgrip and a functional part provided with a plurality of recesses shaped to receive and mate with elements of a free-wheel unit, and cooperating with at least two locking pin members, and a second tool comprising a handle, provided at one end with a half-moon shaped body having a length of bicycle transmission chain pivotally connected to one end thereof. The recesses in said first tool are apt to mate with the outer profile as well as with the wall of an inner hole of the free-wheel unit elements having to be applied to said tool. The second tool comprises, in order to engage the sprocket wheels of said free-wheel unit, on one hand said transmission chain length and, on the other hand, a pair of chain links mounted so as to form an articulated parallelogram.

Abstract: In a pedal for bicycles there is provided a slanting guide extending from the top of the longitudinal element close to the toe clip of the peripheral band of the pedal, towards the central pin of the pedal itself.

Abstract: A fixture for the assembly and disassembly of special gears (particularly of gears of free-wheels applied to the rear wheel of bicycles) consists of a first tool which comprises an appropriately shaped, metal elongated plate, having a smooth handgrip and a functional part provided with a plurality of impressions corresponding to elements of a free-wheel unit and apt to house at least part of said elements by mating with their shape so as to prevent rotation thereof, threaded holes being provided at the center of said impressions, and at least two locking pin members apt to be screwed into said threaded holes for locking on the plate, in said impressions, the elements of the free-wheel unit having to be handled, and of a second tool of the type comprising a handle terminating with a halfmoon shaped body, to an end of which is pivoted a transmission chain section for bicycles, a notch being provided along the whole inner archway of the half-moon shaped body of said tool, for housing the periphery of a gear with

Abstract: Improvements in the mounting of the transmission chain of bicycles for guiding and supporting the chain, comprising an arc-shaped guide applied on the inner side of the end of the rear fork of the bicycle, substantially concentric to the axis of the rear wheel of the bicycle itself, and mechanism for controlling the change-speed gear, which comprise a control lever rotatable with high friction into an appropriate seat of a clamp fixed to the front tube of the bicycle frame, to which lever is connected the change-speed gear control cable, a pawl mounted on said lever freely oscillating against the action of a spring, and a fixed stirrup associated with said seat and/or clamp. The pawl is adapted to cooperate with two ratchet gear teeth of the stirrup to permit movement of the chain to either an adjacent sprocket or to the guide.

Abstract: In a disk brake for motorcycles, the brake disk connects the actual hub of the wheel with the spokes-carrying flanged body of the wheel itself, and the braking member consists of a non-rotating plate, provided with friction pads slidable along the wheel axis. The disk braking surface is a conical surface, with its axis coinciding with the wheel axis, and the friction pads are borne by the plate in such a way as to lie on a conical surface mating with the disk braking surface. The brake plate is widely slotted, so as to provide a unit comprising a hub, three spokes and two peripheral crowns, this unit being obtained by metal casting, the friction pads being applied to the spokes between one crown and the other.

Abstract: Adjustable saddle support for bicycle comprising a pillar, a head and means for supporting a saddle in an adjustable position, said means being in engagement with said head by way of at least a pair of complementary curved surfaces under the action of a single coupling member.

Abstract: A disk brake, of the type embodying the brake disk in the hub of the vehicle wheel and especially a motorcycle wheel, having: at least one brake disk, the braking surface of which is a conical surface, which brake disk connects the actual hub of the wheel with the spokes carrying flange of the wheel itself; and at least one non-rotating brake plate, placed to the side of the hub and provided with friction pads lying on a conical surface adapted to engage with the braking surface of the disk, said brake plate being slidable along the wheel axis in order to establish or interrupt braking engagement between said friction pads and said disk, under the opposing action of fluid pressure control means and of spring return means.

Abstract: A disk brake, of the type embodying the brake disk in the hub of the vehicle wheel and especially a motorcycle wheel having: a ring-shaped brake disk supported by a ribbed disk of the hub; a brake plate axially movable but locked against rotation; fluid pressure control means for driving the plate into friction engagement with said ring-shaped brake disk and return means acting against said control means.