I have 3 rovers, and 2 need some maintenance after a 7000 mile cross-country RV trip. They were exposed to a lot of road grime and some rain while on the hitch. I've noticed some brake loss, and chain rust(!) and want to get them performing good as new. I live in S.F, and since I purchased my rovers online from utah trikes, I don't have a local trike shop. Any suggestions?