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.
Stainless steel holder for mounting an on-board socket...
Aluminum protective cover for the safety switch on the side...
These handlebar risers for your BMW R1250R let you sit up...