Abstract: A telescopic element, particularly for frames of folding bicycles, comprising a sliding inner element that can be locked in an operating position within an outer element by a quick locking element, the locking element comprising a ring that is normally in the position for locking the axial movement of the inner element with respect to the outer element, the locking element being movable radially by means of a release button.

Abstract: Transmission assembly, particularly for bicycles or the like, having an inside box-like body, a first chain ring associated with a pedal crank shaft and connected to a pinion by a first chain, and a second chain ring associated with a second shaft and rotating rigidly with said pinion. A second chain is associated with the second chain ring and is adapted to transmit the motion to a gearshift assembly constituted by a plurality of gears that can be selectively associated with the second chain by a derailleur. The gearshift assembly is rigidly coupled to a hub that supports a wheel in a cantilevered manner outside the box-like body.