I purchased a new 2013 R1200GS a few weeks ago. Upon leaving the dealership and up through 500mi everything seemed great. I took the bike in for 600 mi service, added vario siade and top case and now have a somewhat violent head shake between 40-55 mph. According to service there are no recalls for my motorcycle but I will be dropping it off in the morning so this can be fixed somehow! Really concerned that this may be a design flaw!!!