My son and I just put new IPT 589s on our Sportsmen (500HO, 700). One of his was badly out of balance and had to returned for replacement. Now that I have mine mounted I find that two of mine are also out of round to the point that riding 30MPH is very uncomfortable. I will be returning them also. Three bad tires out of eight is an unacceptable percentage. Has anyone else experienced this? Is there any explanation (other than poor qualaity control by IPT)......Trapperg