The Meg-Mo blades are in perfect balance at all times. Centrifical force does this. The blades you are using are balanced when you put them on. When you take your blades off to sharpen they have a nick in them. When did this happen, right after you put them on or just before you took them off? With a nick in your blades they are out of balance. Meg-Mo blades don't just nick and tip speed does not have anything to do with this. We have blades on Dixie Choppers, Exmark, John Deere, Hustler and all 70 or 80 other brands of mowers, including the new Bad Boy. We invented these blades on a JD and an Exmark and both machines are 12 or 13 years old and still out perform any other mower out there. All mower manufactures tell how great their machines are, but all use 70 year old technology in their blades. Six or seven companies make all blades used today on mowers. They have told us that we are just selling blades. I was tired of what you people are putting up with so now we make apleasure out of mowing.