DC1964 I have almost the same problem and took it to tne dealer.at the time they told me that synthetic oil was too thin and was causing the oil usage so went back to the recommended oil now have taken it to the dealer with a knocking noise and they tell me that Kawasaki recommends putting synthetic oil in it as the recommended oil was too thick to reach the top of the engine, so now i am totally confused hope somebody on here has an answer.....????? I have an 04 VN2000 with 45000 miles