I recently acquired a Model Power 2-6-0 with a terrible wobble while running. I ruled out out of round wheels, so the culprit had to be traction tires. I removed both and reseated them as well as I could, but no help, still as wobbly as ever. Out of desperation, I soaked a paper towel with rubbing alcohol and put it on the track, just like I do when cleaning wheels. Using gentle pressure, I ran the loco, moving it side to side and back and forth for around a minute. To my surprise, this solved the issue entirely, and the little guy is smooth as silk. I suppose the alcohol got between the traction tire and the wheel, and allowed it to kind of slip and slide around until it found the perfect seat. So if you've got a wobbly loco, you might give this technique a try!
