I stole my son's wheel brush which he got at Target, he doesn't use it. Its about 12" long and I think the key here is that like Fritzauf's its bendable, good for getting in behind the spokes and the back of the wheels. My hands are small enough where I can get back into the rear wheels. Doing that and cleaning the wheel wells when you wash really makes a difference. I just painted my brake calipers and when I had the wheels off I gave the back sides a thorough cleaning.

Pat