Originally Posted by
BCRider
If you flip the wheel around it will tell you if there's some sort of minor rim runout or dishing issue or if the issue is at the axle or if it's in the dropouts.
+1,
This is the definitive test. A wheel problem will mirror when the wheel is flipped, a frame problem. If in doubt, borrow another wheel and reconfirm. I also confirm an axle issue by rotating the axle in the dropout with the bike standing on the floor.
This brings up a key point, always mount rear wheels with the bike on the ground, so gravity ensures the axle is at the top of the dropouts.
If you're 100% certain it is a frame issue, things get complicated, because it could be a bent (or badly built) rear triangle, or it could be dropouts at unequal heights. Before you can fix it, you have to confirm a correct diagnosis, and that's too long for me to explain here. If you think it's the frame, either see a knowledgeable dealer, or search frame alignment on the net.