I have straight honed wheel cylinders before. I don't completely recommend it though. It has to be a "fixed" staight hone though (like a sunnen). I would shoot for .005" to .007" max. to clean them up. As long as there are not pits where the cups ride you will be OK. If there are pits in the center where the spring is, and th ecups don't ride , that won't effect anything. If you can find replacements for $25 or less, I wouldn't bother trying to hone them. Be careful and know what you are doing when trying to hone them. Bad brakes will cost you much more than new ones.
