Rear sprocket for bicycle transmission

A rear sprocket comprising:

• an inner attachment portion having a first lateral surface facing in a first axial direction, a second lateral surface facing in a second axial direction and an inner peripheral edge extending between the first and second lateral surfaces;
• an annular root portion located radially outward of the inner attachment portion with the annular root portion having a first side surface facing in the first axial direction and a second side surface facing the second axial direction such that the second side surface and the second lateral surface lie in a common plane;
• a main body portion connecting the inner attachment portion to the annular root portion;
• and
• a plurality of teeth extending radially outward from an outer periphery of the root portion,
• the inner peripheral edge of the inner attachment portion having a plurality of hub engaging projections defining a plurality of hub engaging slots disposed between the hub engaging projections, and
• the inner attachment portion including a plurality of individually spaced apart recesses formed on the first lateral surface and extending radially outwardly from the inner peripheral edge, the recesses extending radially outwardly from the hub engaging slots such that the inner attachment portion has an axial thickness measured at the recesses that is smaller than an axial thickness of the inner attachment portion measured at the hub engaging projections, the axial thickness of the inner attachment portion measured at the hub engaging projections being the same as an axial thickness of the main body portion.