Bicycle gear shifting system

A bicycle front shifting assembly, comprising:

• a front shift unit configured to be coupled to a crank assembly for rotation therewith about a rotation axis, the front shift unit having a chain ring component and a shift mechanism coupled to the chain ring component,
• wherein the chain ring component has a big chain ring having a plurality of teeth defining a big chainring plane and a small chain ring having a plurality of teeth defining a small chainring plane, the small chain ring having a small diameter and the big chain ring having a big diameter that is larger than the small diameter,
• wherein the shift mechanism includes an upshifting element including at least one protruding shift element disposed in a transition zone between the big chain ring and the small chain ring, the shift mechanism configured to move the at least one protruding shift element axially between the big chainring plane and the small chainring plane, and the shift mechanism also includes at least one downshift element movable relative to the front shift unit to selectively engage a chain to execute a downshift of the chain from the big chain ring to the small chain ring, and
• wherein the at least one protruding shift element is movable to intersect the small chainring plane radially between a root circle and a tooth tip circle of the small chain ring.

A bicycle front shifting assembly, comprising:

• a front shift unit configured to be coupled to a crank assembly for rotation therewith about a rotation axis, the front shift unit having a chain ring component and a shift mechanism coupled to the chain ring component,
• wherein the chain ring component has a big chain ring having a plurality of teeth defining a big chainring plane and a small chain ring having a plurality of teeth defining a small chainring plane, the small chain ring having a small diameter and the big chain ring having a big diameter that is larger than the small diameter,
• wherein the shift mechanism includes an upshifting element including at least one protruding shift element disposed in a transition zone between the big chain ring and the small chain ring, the shift mechanism configured to move the at least one protruding shift element axially between the big chainring plane and the small chainring plane, and the shift mechanism also includes at least one downshift element movable relative to the front shift unit to selectively engage a chain to execute a downshift of the chain from the big chain ring to the small chain ring, and
• wherein the at least one protruding shift element comprises a tooth movable to selectively engage a tooth space between plates of the chain.