Remove the swingarm and then you'll have access to the bearings. Several good videos on YT that show this process.
If the baring are gritty, loose or failing they need to be replaced. You can use OEM which are SKF sealed and seem to be proprietary to BMW or you can use a 30203 tapered roller bearing that is not sealed but works jus the same for a fraction of the price.
Specialty tools needed:
Low value torque wrench able to reliably to do 5 and 6 ft/lbs
High vale torque wrench able to reliable do 107 ft/lbs
Medium range torque wrench able to do 43 and 74 ft/lfs
30 mm socket and reducers to fit you high value torque wrench
12mm Allen socket with reducers to fit the low value torque wrench. There is a special cut out version or you can make you own so that you can back the left side trunnion with a 12mm allen key while you torque the 30mm nut. I have found that backing the trunnion is not needed. Carefully setting the trunnion (part 10) to 5 ft/lbs then torqueing the 30mm nut (part 11) to 107 ft/lbs. iis all thats needed.
Slide hammer with a M6 thread on the end to remove right bearing support.
Blind bearing puller
Also need -
Wheel bearing grease
Aersol brake cleaner
Small brushes for applying spline lube and or anti-seize
Bearing packer if you are not comfortable with hand packing
While you have the swing arm off it also a great opprutinity to replace the rubber boots (at least the upper one at the transmission, part 4) so check them carefully for rips, tears or dry rot and have them on hand if they need replaced. Also a great time to check the drive line splines and U-joints for wear. Then also a good spline cleaning and reapplication of spline lube.