I remove the crankshaft to check the condition of the main bearings. In order to remove it, I have to remove the camshaft first. I use the tools I bought from Cycle Works to remove the crankshaft.
I asked Matt Parkhouse, a long time airhead mechanic who lives about two hours from me, to assess the condition of the crankshaft main journals and the main bearings. He found the front bearing was serviceable but the rear main bearing was just outside the maximum clearance. He replaced the bearing and now the front and rear main bearing clearances are close.
Since I have to heat the front of the engine block to 275 F, I removed the stater motor and crankcase vent housing hose so they would not be damaged.
Here is the block with the crankshaft and camshaft removed.
You can read about how I do this work here:
And here is a short video of the highlights of the work:
VIDEO: 1983 BMW R100RS Remove Camshaft and Crankshaft