The bicycle crankset includes a bottom bracket axle, two cranks and a chainring carrier bearing first and second different toothed chainrings. The chainring carrier has the shape of a star, of which each arm is provided with a mounting hole aligned with a mounting hole in the first and second chainrings respectively. These holes accommodate elements for fastening chainrings to the chainring carrier, and they are arranged on a first circle with a predetermined diameter. Each arm of the chainring carrier is provided with a second mounting hole arranged on a second circle with a diameter that has been reduced relative to the first circle to match the chainring carrier to two other toothed circular chainrings with a size that is respectively reduced relative to the first and second chainrings and of which the mounting holes are located on the second circle.