yeah i have the atc head i tried both soda and glass bead, soda did nice work on clean material to put a dull factory sort of finish, the glass put a shine to it. neither went too well cleaning this motor, I've had to wash then use a wet soft brass brush on low speed on the dremel. then after that as a test i did hit a small patch with soda to see the finish, that will be what i'm after in the end.
I did just buy a wetblast attachment for the pressure wash and may try hot washing as well on some engines to see the different effects it all gives.
the engine I'm aiming for as factory as possible so will clean and seal the cases then paint the clutch and generator covers.
I didn't check the miles before teardown, these bikes have been robbed to pay over the years so i couldn't say they were original odometers.