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 bar end weights made of stainless steel or aluminium...
The adjustable gear lever for the BMW R1250RS is made of...
After just a few thousand kilometers, stones and dirt thrown...