With an allen key or T10 torx (normally supplied in your tool kit) inserted in the a hole on the side you can easily remove the filler cap. With either of these tools you turn the Oil Filler Plug 120° around.
Supplied with the BMW logo.
Fits: R1200GS WC, R1200GS, R1200GS Adventure, R1200R, R1200RT, R1200S, R1200ST.
Hornig Hexhead|OC|Boxer WC Oil Filler Cap w/BMW Logo
Produced by Hornig of Germany