A rear body panel for a golf car includes a seat support portion and a bag well portion disposed rearward from the seat support portion. Accordingly, it is possible to prevent leak of oil from the oil supply hole and thereby reliably lubricating the position between the connection tubular part of the sub connecting rod and the crank pin by a splash lubrication system. A throttle assembly can also be used to regulate the rate of pneumatic flow from the air reservoir to the air spring. One implementation monitors the RF energy escaping to dynamically adjust the power of the overlay signal as required.