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.
These aluminium parts cover the big holes above the foot...
These covers for the open holes beyond the seat are made of...
Rear wheel centre cover with emblem. The holes in the...