Yea... a models texture should be a power of two. But that's not what I was addresing. Who in the world would take one of these above textures, turn it 64x64 ect. and apply it to a wheel? A wheels uv map contains more than just the tread, there is also the rims... Therefore, these textures are fine as are, because they are "concept images". It would be impossible for someone to release a ready-to-go texture without sharing a wheel model at the same time.