Sorry to say, after decades of owning spoke wheeled motorcycles, I've found no magic bullet for cleaning wheels.
On wash day I use a variety of brushes and maybe even scotch bright pads on individual spokes to get the wheels clean. I clean with the regular bucket of bike wash. Sometimes using a spray bottle of Simple Green, just don't leave it too long it will etch bare aluminum. I've thought of using some sort of Automotive Wheel Cleaner but haven't gone that far, yet.
What I don't miss is getting chain lube off the rear. Plus one for shaft drive!