New to the ATV life and purchased this machine a few weeks ago. The owner stated that the machine had been sitting in his garage for about two years ever since he rolled it down a hill. I knew this was going to be a fixer up unit, however the machine has plenty of power and I can run up the road at 45 mph easily but it smokes, white blue smokes that smells of oil. I have serviced the engine oil and filter with no change. Any suggestions as to what to do next?