I thought I was going to change my motor also when I first got my lathe, I listened to the advice of the members here and decided to just get a vfd. It's cheaper, gives variable speed, soft start too. If you think about it many manufacturers are using 3 phase motors from the factory now with vfd's already installed so they can run on 110 or 220 single phase. I am almost ready to make my purchase of a vfd, it's the way to go. you wont have to drill anything on your lathe or the motor to get things to line up, a 3 phase motor will last forever, and a vfd is just some simple wireing. Plus keeping the lathe all original holds it's value.