There is provided an engine oil degradation-determining system which is capable of accurately detecting whether or not engine oil has been replenished, to thereby enhance accuracy of determination as to a degradation level of engine oil in use, at a low cost. A first region of the chassis includes a first panel and at least one first side panel. A regulating distance correcting value is determined by the force regulator from the rolling force target value and the rolling force actual value. This reveals that the bike locker is occupied and prevents the use of the locker for unauthorized, privacy-requiring activities. The covering substrate includes a non-metallic covering with a tab defined within the perimeter of the substrate. A storage unit stores the reliability information indicating the reliability of the information of the predetermined type produced by the reliability information producing unit, in association with the information of the predetermined type.