Be careful about tightening the wheel to much. It will cause binding on the bearings and heat up. This is not an issue on a large wheel because there is enough metal there to be a heat sink and not get to hot. On the smaller wheels it can heat up enough to cause the tire to come loose and slide off. I had this problem and contacted Tracy and he told me to use epoxy and glue it back on, which is what the factory does. I did and loosened the pressure on the axel a touch and have had no problem since. Now when I build grinders I make sure that each wheel with bearings has just the slightest movment back and forth. Just enough that you can tell that it is there....Or snug it down then back off just a touch. I was having trouble with the axel backing out so I hit the threads with a hammer, then used a touch of locktite.
