Having read a few threads on StormTroupers, I tried cleaning the spokes with wd40 and gt85 with no improvement. But then tried T-Cut which removed what I thought was pitting and was in fact a stubborn film, which is only on the rear wheel. I use gear oil to lube the chain, and can't figure out what this film that looks like pitting and was near imposable to remove. This was a back breaking and time consuming job, so I have ordered XCP rust blocker in the hope that I don't have to do this to often.