A system and method for connecting parts

A bicycle frame, comprising: a first section (70) including a lower tube (13) and a tube (50) end, and a second section (72) including a connecting tube (30) and a tube (16) seat, wherein the lower tube (13) and the connecting tube (30) are connected, so that they can be separated, by a clamp (20) to form a joint (74) of lower tube, characterized that the tube (50) end and the tube (16) of the seat are connected so that they can be separated, using a shank (17) of the seat as a connecting element to form a junction (76) of the seat tube.