How come some bearings dont fit very well in some wheels??

Question

i have a pair of pig wheels and reds bearing and the bearings keep popping out of the wheels. then the wheel stops spinning, then i tighten the wheel to get the bearing back in and it is fine again. then the next day it happens again

Answer 1

Some times the wheels are so hard that they don't sit in the wheel all the way, make sure when you put them in that you put one bearing in then put it on your truck and with your hands pull the wheel against the truck this will help seed the bearing in snugly.  do the same thing with the other bearing on the other side of the wheel.