A bicycle bottom bracket force sensor includes an outer portion, an inner portion, at least one sensor mounting surface and a strain gauge. The inner portion is dimensioned to receive and support a crank axle bearing that rotatably supports a crank axle. The at least one sensor mounting surface extends between the outer portion and the inner portion has the strain gauge fixed thereto. The sensor mounting surface extends in a direction substantially perpendicular to a rotation axis of the crank axle when the force sensor is coupled to the bicycle bottom bracket.