front brake master cyclinder

My front master cylinder has slight weep from the bottom of the plastic reservoir .I can not find diagram for this but does it have a o ring below the reservoir and its just a case of sucking out the brake fluid from it un do the 2 screws new oil ring back together and top up

Hi, if you look on the MAXBMW web site parts fische it shows an O ring as part number 32 727 675 117. That applies to a 2005-08 bike, you should check for whichever year your bike is. Alan