Zebrafive
Super Member
Though a manual is a great thing to have, you may learn what you need to know from pulling the deck and inspecting the driveline. Does it want to lunge or is it the vibration really you are after? Roll the idler pulleys around to inspect for flat spots on them and the belt as well. A stick in the transaxle cooling fan will raise all kind of heck.
x485 is shaft drive not belt drive