they got left in... and there was suprisingly oil left in the frame too i thought they went throught a pretty good chemical bath before hand...
Most coaters will only sandblast, and coat. A chemical bath would make it worse, trapping liquid in spots, and coming out when it is cured. For anything used that has been around oil, grease, and road grime, you need to bake what you're doing first, before sandblasting.