Martin,
Thanks for sharing your procedures and pics. However, I'm not entirely convinced that this method will work in many circumstances. You stated in another post that all of your clients have their cars washed on a weekly or bi-weekly basis. With such frequent washing, dust buildup and the like will be minimal, so I can see where your method would work great in these instances. On the other hand, it seems I come in contact with many cars that haven't been detailed or washed for that matter in months or even years, therefore, the condition of the wheels is far worse and set in than that shown in the pics above. Many times I've had to resort to using diluted wheel acid to cut through this stuff. I also notice you say you spray the solution on the wheel first, then pw off, then wipe with dash tool. Couple questions, do you spray the solution on the wheels dry or prime with water first? If so, have you ever had a problem with them staining or discoloring? Lastly, how long do you let the simple green dwell on the wheels before pw, and do you use the brush on them while the solution is still dwelling or are you using it after everything has been pw off? Sorry for the long post, just had a few questions that arised after reading your post.
Thanks.
Matt Williams
Silver Lining Detail