I've owned a 2004 R1150RT twin spark (which I never should have sold!) that never had a surging problem. Also owned an R1100GS that surged like a chronic asthmatic; that was pretty much eliminated with the installation of a "Power Commander." I'm now in the market for another R1150RT or an R1100RT. Do the single spark R1150RT or the R1100RT models have a surge problem? Thanks.