I get a number of questions about how I achieve the “like new” patina on the engine block, transmission and rear drive. I previously published two documents on refinishing, so on this project I decided to create a short YouTube video showing the materials and tools I use and how I restore the aluminum to like new condition without bead blasting the engine block. Blasting the block requires complete disassembly and then meticulous and laborious cleaning of all the oil passages to guarantee no bits of glass are inside.
Here is the document and YouTube video I published. The document contains links to the other two documents about how I refinish various parts.
VIDEO: 1983 BMW R80ST Refinish Aluminum Engine Block
And here are some before and after pictures starting with what the R80ST looked like when I first saw it.
Here is what the engine block looked like after I removed it from the frame.
And here is the final result after working about 10 hours over 5 days on refinishing the aluminum block.
I hope this is helpful.
I am in the process of the same work. Thanks for pioneering.