There is a drilling in the side of the plug in which you can put a size 3 Allen key or a Torx key T10 (usually found in the your BMW toolkit) in order to fit and remove it.
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Also referred to as oil filler cap.
This cover for the open hole beyond the swingarm pivot is...
It is nicely machined of aluminum and natural anodized. The...
Aluminum protective cover for the safety switch on the side...