A hot (well cold) topic on the beemer site right now so for all the US/Canada folks you may still be able to get some of these, hope it isn't too late, get one for each bike at that price!
http://www.motorcycle-superstore.com/DoTd.aspx?SiteID=em_DOD_11_26_Text&WT.mc_ID=35967&WT.i_e_dcsvid=1534401358
http://www.motorcycle-superstore.com/DoTd.aspx?SiteID=em_DOD_11_26_Text&WT.mc_ID=35967&WT.i_e_dcsvid=1534401358