Not sure if this helps but it appears to me that the power coater did not prepaparethe wheels correctly
http://www.alu-info.dk/Html/alulib/modul/A00384.htm
Failures in the powder coating process and how to avoid them (Topic: 14112)
Poor earth connection
This fault happens if there is insulation within the circuit. The insulation is most commonly caused by powder coating on the hooks. To avoid this failure the coating has to be removed from the hooks by burning, using a paint stripper, or knocking it off by a hammer. The powder application equipment (the conveyor) should have special earth connection.
Poor cleaning between colour changes
This fault is very easy to observe, especially if the cleaning between colour change from black to white has been poor. Black powder particles will in such cases appear on the white surface. To avoid this thorough cleaning of the powder application equipment has to be carried out between colour changes.
Pin holes
Pin holes appear as small spots without any coating. Pin holes in a powder coating is caused by entrapped moisture from the pre-treatment which evaporate during the curing process. To avoid this defect thorough drying of the profiles needs to be carried out.
Cissing
Cissing is non-uniform wetting of the surface. The fault appears as areas or spots without any coating. To avoid this defect thorough degreasing is necessary.
Down load the consumer complaints form fromt he net fill it out and either send it in or alternatively go to your power coater and say here is the complaint, please fix my wheels or I will be force to lodge the complaint.