our kids have been riding our new honda foreman 500 and we told them they were to maintain it and change the oil and oil filter. they changed the oil and at 1000 miles changed the oil filter however, they put it in backwards and we didn't find out until about 40 later. now we've changed the oil and filter again, put in some additive and it still makes the metal noise but not as bad. i'm afraid to ask, but what has been done to the motor? is there any hope or are we screwed? we live in the alaskan bush, so we pretty much need to work on our own atv. what should we do?