A motorcycle exhaust system includes a catalytic converter disposed within an exhaust passage for discharging exhaust gas from a multi-cylinder combustion engine and operable to purify the exhaust gas. The central office includes a telephone switch that provides telephone service to the subscribers and a concentrator that connects a plurality of upstream repeaters with a number of office modems that provide data service to the subscriber. In one embodiment, there is a means of controlling the drop of the weight bench so that it is lowered gently.