Front chainring assembly

A front chainring assembly comprising:

• a power meter device comprising:
• a body comprising a torque input section and a torque output section, the body configured to transmit power between the torque input section and the torque output section, the torque input section adapted to be coupled to a crank arm, wherein the body is rotatable about a rotation axis, the torque output section comprising an outer periphery comprising power meter threads and an axial stop surface;
• and
• a plurality of circumferentially spaced strain measurement devices spaced radially outwardly from the rotation axis and coupled to the body, the plurality of strain measurement devices configured to provide a signal indicative of a strain detected in the body;
• and
• circuitry interpreting the signal and determining a corresponding power transmitted between the torque input section and the torque output section;
• and
• a chainring structure comprising an inner periphery comprising chainring threads and an outer periphery comprising a plurality of teeth and a axial face, wherein the inner periphery of the chainring structure is threadably engaged with the outer periphery of the torque output section, wherein the axial face comprises a plurality of circumferentially spaced axial projections separated by circumferentially spaced recesses, and wherein the chainring structure is rotatable relative to the body between a disengaged position and an engaged position, wherein the circumferentially spaced axial projections engage the stop surface when the chainring structure is the engaged position and wherein the plurality of strain measurement devices are radially aligned with the recesses when the chainring structure is in the engaged position.