SOMEBODY HELP!!IN OCTOBER 2004 I BOUGHT A SHARPER IMAGE "POCKET ELECTRIC BIKE" FOR $500.00 ; NOW THEY ARE OUT OF BUSINESS, AND I NEED A REAR COMBINED WHEEL/BELT GEAR,WITH THE PNEUMATIC TIRE; I WOULD PREFER A URETHANE REPLACEMENT FOR RELIABILITY..MOST FOLKS HAVE NOT HEARD IF THIS ITEM, BUT I WOULD PAY ANYTHING REASONABLE SO I CAN RIDE AGAIN! HELP!!!