[danielf]

Put 2 bearings on each side of the scale. If they are not equal in weight, the odd one is in this lot. Now check two of these, if these are equal in weight, check one of these against one of the other two. If these are equal in weight, the remaining one is the odd one out. If not, it's the 'new one'. If the first 4 are equal in weight, do the last steps with the other 4.

Edit: Or, in letters. Check AB vs CD. If unequal, check A v B, and the B v C.
If AB = CD repeat last steps with E, F ,G and H.