If you notice Residue on the bearings of your wheel, that is caused by the finish of the wood rubbing off on the bearings. You can take a dry cloth to wipe this residue off. A small amount of residue is normal. However, if you notice the residue when troubleshooting for other wheel issues - it's possible it's been caused by a misaligned treadle.
If you suspect your treadle is no longer in alignment, email videos to help@spinolution.com for troubleshooting.