I've spent a long time cleaning the engine, and it doesn't look too bad now, so I'm not going to paint it black. It is what it is.
The crankcase covers are another story. I haven't touched them so far, but now was the time to get them polished up. The generator side (left side) is pretty severely corroded, so that was going to come off first. Thank goodness for my impact driver; those bolts were on tight and really soft. Not sure if that is a function of being thirty years old, or poor quality material to begin with. I did try to use my cordless impact hammer but it totally stripped the head within about 0.05 seconds. Not doing that again, and thankfully managed to get that bolt off.
With the covers off, I needed to get rid of the old clear-coat that was yellowed and flaking off in places. Best solution for this is a product called Aircraft Cleaner. It's basically a type of paint stripper but doesn't have any caustic in it to damage the aluminum. You can find it at Auto Zone, Walmart, and Home Depot. I used a couple of disposable aluminum roasting tins to keep all the mess in one place. It only takes about 10-15 minutes before you can see all the crap bubbling off, then using some Purple Power to get rid of the cleaner, I then washed them in soapy water. Of course during all this I was wearing gloves and eye protection. It's strong stuff, so be warned.
Next I used 220 grit emery paper to take off the worst of the corrosion. While I was doing that the Suzuki logo started to come off; the aircraft cleaner had worked it's way under this thin badge and softened the glue holding it in place. I carefully pried it off and let it have a second bath in the cleaner. These guys are no longer available anymore so it'll be extra important to try and restore them before remounting on the cases.
So that's the next few hours scheduled. Taking off the worst of the corrosion, rubbing out any big scratches, then taking everything over to the buffing machine. Or maybe I'll finish the frame. We'll see what brings the most enjoyment.
Current hours on build: 21.0