Brake cleaner isnt a good idea to use for the internals, i know its exactly like nitro cleaner and alot cheaper. Brake cleaner has different properties that make it harsher than nitro cleaner. Also might react to certain surfaces

I use household cleaner that removes dirt, grime & soap scum. Works great and stops further dirt from sticking to it. Also a dissinfectant

After run is great to use. They stop gumming inside the engine and keep everything lubricated and rust free. My piston still looks brand new and doesnt have the browning-burnt looking color like most engines