This bike has the Nikasil plated aluminum cylinders. Nikasil is a nickel silicon carbide material that is extremely hard and wears very little and can be platted onto aluminum. That said, I want to measure the cylinders to determine if they are in good condition since the bike sat for about 25 years and had 64,000 miles on it.
I previously measured the cylinders on my 1973 R75/5 and you can see that procedure here.
On this bike, I measure the bore, ovality and taper using a bore gauge to see if these cylinders are still serviceable. I found Both cylinders are in good condition.
After measuring the cylinders I remove the glaze on the cylinder walls using a ball hone. I use the Brush Research Flex-Hone® with 240 grit aluminum-oxide balls that they recommend for Nikasil cylinders. I use a 3-1/2 inch hone and my portable electric drill that has a low speed range of 600 RPM which is within the recommended 500-800 RPM Brush Research recommends.
Here is a link to the document showing all the details of how I do this work and a link to a YouTube video.
VIDEO: 1983 BMW R80ST Cylinder Measurements & Honing