Patent ID: 8721480

Claim:
Bicycle crankset comprising: a bottom bracket axle ( 2 ) with two opposite ends; two cranks, each of said cranks attached to a respective one of the opposite ends of said bottom bracket axle; first and second circular toothed chainrings ( 5 , 6 ) of different sizes, aligned mounting holes ( 12 , 13 ) provided in said first and second chainrings ( 5 , 6 ) respectively; a chainring carrier ( 8 ) provided with a central hole ( 9 ) for accommodating said bottom bracket axle ( 2 ) and bearing the first and second chainrings ( 5 , 6 ), said chainring carrier ( 8 ) having the shape of a star with uniformly spaced arms ( 10 ), each arm ( 10 ) have a free end and being provided near the free end with a first mounting hole ( 11 ) aligned with said aligned mounting holes ( 12 , 13 ) of said first and second chainrings ( 5 , 6 ) respectively; and fastening means ( 14 , 15 ) that extend through said first mounting hole ( 11 ) of each arm and, at the same time, through said aligned mounting holes ( 12 , 13 ) of both of said first and second chainrings ( 5 , 6 ) such that each fastening means ( 14 , 15 ) thereby fastens both said first and second circular toothed chainrings ( 5 , 6 ) to said chainring carrier ( 8 ), wherein, said first mounting hole of each arm ( 11 ) and said aligned mounting holes ( 12 , 13 ) of said first and second chainrings ( 5 , 6 ) are arranged on a first circle (C1) with a predetermined diameter (D1) and centered on said central hole ( 9 ) of the chainring carrier, and wherein each arm ( 10 ) of the chainring carrier ( 8 ) is further provided with a second mounting hole ( 16 ) which is disposed on a second circle (C2) that is concentric relative to said first circle (C1) and having a diameter (D2) that is reduced relative to the diameter (D1) of said first circle (C1), wherein said second mounting hole ( 16 ) of said arms ( 10 ) enables replacement of said first and second chainrings ( 5 , 6 ) by two other first and second circular toothed chainrings ( 5 ′, 6 ′) being compact chainrings with a size that is respectively reduced relative to a size of said first and second chainrings ( 5 , 6 ), and with mounting holes ( 12 , 13 ) located on said second circle (C2), thus obtaining a multipurpose chainring carrier ( 8 ), and wherein, each arm of said chainring carrier ( 8 ) extends substantially radially, each arm ( 10 ) of said chainring carrier ( 8 ) is defined by two lateral sides ( 17 , 18 ) that are essentially parallel to one another and connected by an end side ( 19 ), and said end side ( 19 ) is oblique relative to said lateral sides ( 17 , 18 ), and said first mounting hole and said second mounting hole of each arm are aligned to one another parallel to said end side.