We purchased a pioneer 700 4 seater two years ago. It is starting to use large amounts of oil. When it is parked in the shop you do not see oil dripping. Not sure where it would be going. Engine runs well. Does sound loud. No smoking when it is running. Did and oil change after it was low the first time. About a week later it was down 1 1/2 L. Took it in to Honda and they have no idea. Any suggestions would be helpful.