Let my stepson borrow my quad for a medium run with slight hills mostly in woods riding old creek bottoms. Since then I’ve noticed a looping or lurching of machine at speeds below 5 MPH. On flat ground you have to have engine RPM’s at around 2000 before bike starts to move. My main concern is the lurching foreword at idle or lil above. What could be my problem? Did he burn the belt. which I have not smelled at all..Thanks..Ricky:ugh2: