V-wheels won't move

When I screw the nuts for the v-wheels tight enough (no slack) they become more or less hard to turn. Seems like either the screw head or the washer somehow block the bearing. Any ideas on how to resolve this? I currently put washers on both sides but this didn’t help as well.

I had this same problem with the v-wheels when I was first building my shapeoko2. My problem was that I had forgot to put a 1mm precision spacer between the two bearings before press fitting the bearings into the v-wheel. Without the spacer, when the mounting bolt is tightened, the two inside rings of the bearings get pushed toward eachother creating high friction within each bearing.

I have a shapeoko 2 as well and didn’t have the problem there. With the xcarve, the bearings were already pressed into the v-wheels. I will tear one of them apart and check. However, its a bit odd that all of them have the same issue.