Recently bought an antique saxony wheel and had bobbinboy replace some parts for me. Now my problem is the drive wheel seems very lopsided! It doesnt want to go all the way around, just rocks back and forth, like one side of it is much heavier. If i can get it going, i can get it to go around for a little bit but it still "tugs" really hard at one point in its cycle. Is this a wood density issue? What is going on here? How do i fix it? Thank you!